diff --git a/api/current.txt b/api/current.txt
index 4c3110c..2303f8d 100644
--- a/api/current.txt
+++ b/api/current.txt
@@ -12635,8 +12635,8 @@
 
   public class Resources {
     ctor @Deprecated public Resources(android.content.res.AssetManager, android.util.DisplayMetrics, android.content.res.Configuration);
-    method public void addLoader(@NonNull android.content.res.loader.ResourceLoader, @NonNull android.content.res.loader.ResourcesProvider, @IntRange(from=0) int);
-    method public int addLoader(@NonNull android.content.res.loader.ResourceLoader, @NonNull android.content.res.loader.ResourcesProvider);
+    method public void addLoader(@NonNull android.content.res.loader.ResourcesLoader);
+    method public void clearLoaders();
     method public final void finishPreloading();
     method public final void flushLayoutCache();
     method @NonNull public android.content.res.XmlResourceParser getAnimation(@AnimRes @AnimatorRes int) throws android.content.res.Resources.NotFoundException;
@@ -12663,7 +12663,7 @@
     method @NonNull public int[] getIntArray(@ArrayRes int) throws android.content.res.Resources.NotFoundException;
     method public int getInteger(@IntegerRes int) throws android.content.res.Resources.NotFoundException;
     method @NonNull public android.content.res.XmlResourceParser getLayout(@LayoutRes int) throws android.content.res.Resources.NotFoundException;
-    method @NonNull public java.util.List<android.util.Pair<android.content.res.loader.ResourceLoader,android.content.res.loader.ResourcesProvider>> getLoaders();
+    method @NonNull public java.util.List<android.content.res.loader.ResourcesLoader> getLoaders();
     method @Deprecated public android.graphics.Movie getMovie(@RawRes int) throws android.content.res.Resources.NotFoundException;
     method @NonNull public String getQuantityString(@PluralsRes int, int, java.lang.Object...) throws android.content.res.Resources.NotFoundException;
     method @NonNull public String getQuantityString(@PluralsRes int, int) throws android.content.res.Resources.NotFoundException;
@@ -12691,8 +12691,8 @@
     method public android.content.res.AssetFileDescriptor openRawResourceFd(@RawRes int) throws android.content.res.Resources.NotFoundException;
     method public void parseBundleExtra(String, android.util.AttributeSet, android.os.Bundle) throws org.xmlpull.v1.XmlPullParserException;
     method public void parseBundleExtras(android.content.res.XmlResourceParser, android.os.Bundle) throws java.io.IOException, org.xmlpull.v1.XmlPullParserException;
-    method public int removeLoader(@NonNull android.content.res.loader.ResourceLoader);
-    method public void setLoaders(@Nullable java.util.List<android.util.Pair<android.content.res.loader.ResourceLoader,android.content.res.loader.ResourcesProvider>>);
+    method public void removeLoader(@NonNull android.content.res.loader.ResourcesLoader);
+    method public void setLoaders(@NonNull java.util.List<android.content.res.loader.ResourcesLoader>);
     method @Deprecated public void updateConfiguration(android.content.res.Configuration, android.util.DisplayMetrics);
     field @AnyRes public static final int ID_NULL = 0; // 0x0
   }
@@ -12762,27 +12762,37 @@
 
 package android.content.res.loader {
 
-  public class DirectoryResourceLoader implements android.content.res.loader.ResourceLoader {
-    ctor public DirectoryResourceLoader(@NonNull java.io.File);
+  public interface AssetsProvider {
+    method @Nullable public default java.io.InputStream loadAsset(@NonNull String, int) throws java.io.IOException;
+    method @Nullable public default android.os.ParcelFileDescriptor loadAssetParcelFd(@NonNull String) throws java.io.IOException;
+  }
+
+  public class DirectoryAssetsProvider implements android.content.res.loader.AssetsProvider {
+    ctor public DirectoryAssetsProvider(@NonNull java.io.File);
     method @Nullable public java.io.File findFile(@NonNull String);
     method @NonNull public java.io.File getDirectory();
   }
 
-  public interface ResourceLoader {
-    method @Nullable public default java.io.InputStream loadAsset(@NonNull String, int) throws java.io.IOException;
-    method @Nullable public default android.os.ParcelFileDescriptor loadAssetFd(@NonNull String) throws java.io.IOException;
-    method @Nullable public default android.graphics.drawable.Drawable loadDrawable(@NonNull android.util.TypedValue, int, int, @Nullable android.content.res.Resources.Theme);
-    method @Nullable public default android.content.res.XmlResourceParser loadXmlResourceParser(@NonNull String, @AnyRes int);
+  public class ResourcesLoader {
+    ctor public ResourcesLoader();
+    method public void addProvider(@NonNull android.content.res.loader.ResourcesProvider);
+    method public void clearProviders();
+    method @NonNull public java.util.List<android.content.res.loader.ResourcesProvider> getProviders();
+    method public void removeProvider(@NonNull android.content.res.loader.ResourcesProvider);
+    method public void setProviders(@NonNull java.util.List<android.content.res.loader.ResourcesProvider>);
   }
 
-  public final class ResourcesProvider implements java.lang.AutoCloseable java.io.Closeable {
+  public class ResourcesProvider implements java.lang.AutoCloseable java.io.Closeable {
     method public void close();
-    method @NonNull public static android.content.res.loader.ResourcesProvider empty();
+    method @NonNull public static android.content.res.loader.ResourcesProvider empty(@NonNull android.content.res.loader.AssetsProvider);
+    method @Nullable public android.content.res.loader.AssetsProvider getAssetsProvider();
     method @NonNull public static android.content.res.loader.ResourcesProvider loadFromApk(@NonNull android.os.ParcelFileDescriptor) throws java.io.IOException;
+    method @NonNull public static android.content.res.loader.ResourcesProvider loadFromApk(@NonNull android.os.ParcelFileDescriptor, @Nullable android.content.res.loader.AssetsProvider) throws java.io.IOException;
     method @NonNull public static android.content.res.loader.ResourcesProvider loadFromApk(@NonNull android.os.SharedMemory) throws java.io.IOException;
-    method @NonNull public static android.content.res.loader.ResourcesProvider loadFromArsc(@NonNull android.os.ParcelFileDescriptor) throws java.io.IOException;
-    method @NonNull public static android.content.res.loader.ResourcesProvider loadFromArsc(@NonNull android.os.SharedMemory) throws java.io.IOException;
+    method @NonNull public static android.content.res.loader.ResourcesProvider loadFromApk(@NonNull android.os.SharedMemory, @Nullable android.content.res.loader.AssetsProvider) throws java.io.IOException;
     method @NonNull public static android.content.res.loader.ResourcesProvider loadFromSplit(@NonNull android.content.Context, @NonNull String) throws java.io.IOException;
+    method @NonNull public static android.content.res.loader.ResourcesProvider loadFromTable(@NonNull android.os.ParcelFileDescriptor, @Nullable android.content.res.loader.AssetsProvider) throws java.io.IOException;
+    method @NonNull public static android.content.res.loader.ResourcesProvider loadFromTable(@NonNull android.os.SharedMemory, @Nullable android.content.res.loader.AssetsProvider) throws java.io.IOException;
   }
 
 }
diff --git a/core/java/android/app/ActivityThread.java b/core/java/android/app/ActivityThread.java
index 2ca5b1d..247ddb6 100644
--- a/core/java/android/app/ActivityThread.java
+++ b/core/java/android/app/ActivityThread.java
@@ -2206,7 +2206,7 @@
     Resources getTopLevelResources(String resDir, String[] splitResDirs, String[] overlayDirs,
             String[] libDirs, int displayId, LoadedApk pkgInfo) {
         return mResourcesManager.getResources(null, resDir, splitResDirs, overlayDirs, libDirs,
-                displayId, null, pkgInfo.getCompatibilityInfo(), pkgInfo.getClassLoader());
+                displayId, null, pkgInfo.getCompatibilityInfo(), pkgInfo.getClassLoader(), null);
     }
 
     @UnsupportedAppUsage
diff --git a/core/java/android/app/ContextImpl.java b/core/java/android/app/ContextImpl.java
index b7555ee..136c84e 100644
--- a/core/java/android/app/ContextImpl.java
+++ b/core/java/android/app/ContextImpl.java
@@ -46,6 +46,7 @@
 import android.content.res.CompatibilityInfo;
 import android.content.res.Configuration;
 import android.content.res.Resources;
+import android.content.res.loader.ResourcesLoader;
 import android.database.DatabaseErrorHandler;
 import android.database.sqlite.SQLiteDatabase;
 import android.database.sqlite.SQLiteDatabase.CursorFactory;
@@ -100,6 +101,7 @@
 import java.nio.ByteOrder;
 import java.nio.file.Path;
 import java.util.ArrayList;
+import java.util.List;
 import java.util.Objects;
 import java.util.concurrent.Executor;
 
@@ -2217,7 +2219,8 @@
     }
 
     private static Resources createResources(IBinder activityToken, LoadedApk pi, String splitName,
-            int displayId, Configuration overrideConfig, CompatibilityInfo compatInfo) {
+            int displayId, Configuration overrideConfig, CompatibilityInfo compatInfo,
+            List<ResourcesLoader> resourcesLoader) {
         final String[] splitResDirs;
         final ClassLoader classLoader;
         try {
@@ -2234,7 +2237,8 @@
                 displayId,
                 overrideConfig,
                 compatInfo,
-                classLoader);
+                classLoader,
+                resourcesLoader);
     }
 
     @Override
@@ -2249,7 +2253,7 @@
             final int displayId = getDisplayId();
 
             c.setResources(createResources(mToken, pi, null, displayId, null,
-                    getDisplayAdjustments(displayId).getCompatibilityInfo()));
+                    getDisplayAdjustments(displayId).getCompatibilityInfo(), null));
             if (c.mResources != null) {
                 return c;
             }
@@ -2284,7 +2288,7 @@
             final int displayId = getDisplayId();
 
             c.setResources(createResources(mToken, pi, null, displayId, null,
-                    getDisplayAdjustments(displayId).getCompatibilityInfo()));
+                    getDisplayAdjustments(displayId).getCompatibilityInfo(), null));
             if (c.mResources != null) {
                 return c;
             }
@@ -2328,7 +2332,8 @@
                 displayId,
                 null,
                 mPackageInfo.getCompatibilityInfo(),
-                classLoader));
+                classLoader,
+                mResources.getLoaders()));
         return context;
     }
 
@@ -2342,8 +2347,10 @@
                 mSplitName, mToken, mUser, mFlags, mClassLoader, null);
 
         final int displayId = getDisplayId();
+
         context.setResources(createResources(mToken, mPackageInfo, mSplitName, displayId,
-                overrideConfiguration, getDisplayAdjustments(displayId).getCompatibilityInfo()));
+                overrideConfiguration, getDisplayAdjustments(displayId).getCompatibilityInfo(),
+                mResources.getLoaders()));
         return context;
     }
 
@@ -2357,8 +2364,10 @@
                 mSplitName, mToken, mUser, mFlags, mClassLoader, null);
 
         final int displayId = display.getDisplayId();
+
         context.setResources(createResources(mToken, mPackageInfo, mSplitName, displayId,
-                null, getDisplayAdjustments(displayId).getCompatibilityInfo()));
+                null, getDisplayAdjustments(displayId).getCompatibilityInfo(),
+                mResources.getLoaders()));
         context.mDisplay = display;
         return context;
     }
@@ -2564,7 +2573,7 @@
         ContextImpl context = new ContextImpl(null, systemContext.mMainThread, packageInfo, null,
                 null, null, null, 0, null, null);
         context.setResources(createResources(null, packageInfo, null, displayId, null,
-                packageInfo.getCompatibilityInfo()));
+                packageInfo.getCompatibilityInfo(), null));
         context.updateDisplay(displayId);
         context.mIsSystemOrSystemUiContext = true;
         return context;
@@ -2637,7 +2646,8 @@
                 displayId,
                 overrideConfiguration,
                 compatInfo,
-                classLoader));
+                classLoader,
+                packageInfo.getApplication().getResources().getLoaders()));
         context.mDisplay = resourcesManager.getAdjustedDisplay(displayId,
                 context.getResources());
         return context;
diff --git a/core/java/android/app/LoadedApk.java b/core/java/android/app/LoadedApk.java
index f0d0e98..44c2486 100644
--- a/core/java/android/app/LoadedApk.java
+++ b/core/java/android/app/LoadedApk.java
@@ -365,7 +365,8 @@
                 mResources = ResourcesManager.getInstance().getResources(null, mResDir,
                         splitPaths, mOverlayDirs, mApplicationInfo.sharedLibraryFiles,
                         Display.DEFAULT_DISPLAY, null, getCompatibilityInfo(),
-                        getClassLoader());
+                        getClassLoader(), mApplication == null ? null
+                                : mApplication.getResources().getLoaders());
             }
         }
         mAppComponentFactory = createAppFactory(aInfo, mDefaultClassLoader);
@@ -1158,7 +1159,7 @@
             mResources = ResourcesManager.getInstance().getResources(null, mResDir,
                     splitPaths, mOverlayDirs, mApplicationInfo.sharedLibraryFiles,
                     Display.DEFAULT_DISPLAY, null, getCompatibilityInfo(),
-                    getClassLoader());
+                    getClassLoader(), null);
         }
         return mResources;
     }
diff --git a/core/java/android/app/ResourcesManager.java b/core/java/android/app/ResourcesManager.java
index 7ab85a4..d09f0bc 100644
--- a/core/java/android/app/ResourcesManager.java
+++ b/core/java/android/app/ResourcesManager.java
@@ -32,7 +32,7 @@
 import android.content.res.Resources;
 import android.content.res.ResourcesImpl;
 import android.content.res.ResourcesKey;
-import android.content.res.loader.ResourceLoader;
+import android.content.res.loader.ResourcesLoader;
 import android.hardware.display.DisplayManagerGlobal;
 import android.os.IBinder;
 import android.os.Process;
@@ -46,7 +46,6 @@
 import android.view.Display;
 import android.view.DisplayAdjustments;
 
-import com.android.internal.annotations.GuardedBy;
 import com.android.internal.annotations.VisibleForTesting;
 import com.android.internal.util.ArrayUtils;
 import com.android.internal.util.IndentingPrintWriter;
@@ -57,9 +56,7 @@
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
-import java.util.Collections;
 import java.util.List;
-import java.util.Map;
 import java.util.Objects;
 import java.util.WeakHashMap;
 import java.util.function.Predicate;
@@ -98,52 +95,6 @@
             new ArrayMap<>();
 
     /**
-     * A list of {@link Resources} that contain unique {@link ResourcesImpl}s.
-     *
-     * These are isolated so that {@link ResourceLoader}s can be added and removed without
-     * affecting other instances.
-     *
-     * When a reference is added here, it is guaranteed that the {@link ResourcesImpl}
-     * it contains is unique to itself and will never be set to a shared reference.
-     */
-    @GuardedBy("this")
-    private List<ResourcesWithLoaders> mResourcesWithLoaders = Collections.emptyList();
-
-    private static class ResourcesWithLoaders {
-
-        private WeakReference<Resources> mResources;
-        private ResourcesKey mResourcesKey;
-
-        @Nullable
-        private WeakReference<IBinder> mActivityToken;
-
-        ResourcesWithLoaders(Resources resources, ResourcesKey resourcesKey,
-                IBinder activityToken) {
-            this.mResources = new WeakReference<>(resources);
-            this.mResourcesKey = resourcesKey;
-            this.mActivityToken = new WeakReference<>(activityToken);
-        }
-
-        @Nullable
-        Resources resources() {
-            return mResources.get();
-        }
-
-        @Nullable
-        IBinder activityToken() {
-            return mActivityToken == null ? null : mActivityToken.get();
-        }
-
-        ResourcesKey resourcesKey() {
-            return mResourcesKey;
-        }
-
-        void updateKey(ResourcesKey newKey) {
-            mResourcesKey = newKey;
-        }
-    }
-
-    /**
      * A list of Resource references that can be reused.
      */
     @UnsupportedAppUsage
@@ -219,6 +170,11 @@
     private final ArrayMap<Pair<Integer, DisplayAdjustments>, WeakReference<Display>>
             mAdjustedDisplays = new ArrayMap<>();
 
+    /**
+     * Callback implementation for handling updates to Resources objects.
+     */
+    private final UpdateHandler mUpdateCallbacks = new UpdateHandler();
+
     @UnsupportedAppUsage
     public ResourcesManager() {
     }
@@ -253,24 +209,6 @@
                 }
             }
 
-            for (int i = mResourcesWithLoaders.size() - 1; i >= 0; i--) {
-                ResourcesWithLoaders resourcesWithLoaders = mResourcesWithLoaders.get(i);
-                Resources resources = resourcesWithLoaders.resources();
-                if (resources == null) {
-                    continue;
-                }
-
-                final ResourcesKey key = resourcesWithLoaders.resourcesKey();
-                if (key.isPathReferenced(path)) {
-                    mResourcesWithLoaders.remove(i);
-                    ResourcesImpl impl = resources.getImpl();
-                    if (impl != null) {
-                        impl.flushLayoutCache();
-                    }
-                    count++;
-                }
-            }
-
             Log.i(TAG, "Invalidated " + count + " asset managers that referenced " + path);
 
             for (int i = mCachedApkAssets.size() - 1; i >= 0; i--) {
@@ -513,6 +451,12 @@
             }
         }
 
+        if (key.mLoaders != null) {
+            for (final ResourcesLoader loader : key.mLoaders) {
+                builder.addLoader(loader);
+            }
+        }
+
         return builder.build();
     }
 
@@ -570,16 +514,6 @@
 
             pw.print("resource impls: ");
             pw.println(countLiveReferences(mResourceImpls.values()));
-
-            int resourcesWithLoadersCount = 0;
-            for (int index = 0; index < mResourcesWithLoaders.size(); index++) {
-                if (mResourcesWithLoaders.get(index).resources() != null) {
-                    resourcesWithLoadersCount++;
-                }
-            }
-
-            pw.print("resources with loaders: ");
-            pw.println(resourcesWithLoadersCount);
         }
     }
 
@@ -660,19 +594,6 @@
      */
     private @Nullable ResourcesKey findKeyForResourceImplLocked(
             @NonNull ResourcesImpl resourceImpl) {
-        int size = mResourcesWithLoaders.size();
-        for (int index = 0; index < size; index++) {
-            ResourcesWithLoaders resourcesWithLoaders = mResourcesWithLoaders.get(index);
-            Resources resources = resourcesWithLoaders.resources();
-            if (resources == null) {
-                continue;
-            }
-
-            if (resourceImpl == resources.getImpl()) {
-                return resourcesWithLoaders.resourcesKey();
-            }
-        }
-
         int refCount = mResourceImpls.size();
         for (int i = 0; i < refCount; i++) {
             WeakReference<ResourcesImpl> weakImplRef = mResourceImpls.valueAt(i);
@@ -722,30 +643,10 @@
     @Nullable
     private Resources findResourcesForActivityLocked(@NonNull IBinder targetActivityToken,
             @NonNull ResourcesKey targetKey, @NonNull ClassLoader targetClassLoader) {
-        int size = mResourcesWithLoaders.size();
-        for (int index = 0; index < size; index++) {
-            ResourcesWithLoaders resourcesWithLoaders = mResourcesWithLoaders.get(index);
-            Resources resources = resourcesWithLoaders.resources();
-            if (resources == null) {
-                continue;
-            }
-
-            IBinder activityToken = resourcesWithLoaders.activityToken();
-            ResourcesKey key = resourcesWithLoaders.resourcesKey();
-
-            ClassLoader classLoader = resources.getClassLoader();
-
-            if (Objects.equals(activityToken, targetActivityToken)
-                    && Objects.equals(key, targetKey)
-                    && Objects.equals(classLoader, targetClassLoader)) {
-                return resources;
-            }
-        }
-
         ActivityResources activityResources = getOrCreateActivityResourcesStructLocked(
                 targetActivityToken);
 
-        size = activityResources.activityResources.size();
+        final int size = activityResources.activityResources.size();
         for (int index = 0; index < size; index++) {
             WeakReference<Resources> ref = activityResources.activityResources.get(index);
             Resources resources = ref.get();
@@ -771,6 +672,7 @@
         Resources resources = compatInfo.needsCompatResources() ? new CompatResources(classLoader)
                 : new Resources(classLoader);
         resources.setImpl(impl);
+        resources.setCallbacks(mUpdateCallbacks);
         activityResources.activityResources.add(new WeakReference<>(resources));
         if (DEBUG) {
             Slog.d(TAG, "- creating new ref=" + resources);
@@ -784,6 +686,7 @@
         Resources resources = compatInfo.needsCompatResources() ? new CompatResources(classLoader)
                 : new Resources(classLoader);
         resources.setImpl(impl);
+        resources.setCallbacks(mUpdateCallbacks);
         mResourceReferences.add(new WeakReference<>(resources));
         if (DEBUG) {
             Slog.d(TAG, "- creating new ref=" + resources);
@@ -795,7 +698,7 @@
     /**
      * Creates base resources for an Activity. Calls to
      * {@link #getResources(IBinder, String, String[], String[], String[], int, Configuration,
-     * CompatibilityInfo, ClassLoader)} with the same activityToken will have their override
+     * CompatibilityInfo, ClassLoader, List)} with the same activityToken will have their override
      * configurations merged with the one specified here.
      *
      * @param activityToken Represents an Activity.
@@ -820,7 +723,8 @@
             int displayId,
             @Nullable Configuration overrideConfig,
             @NonNull CompatibilityInfo compatInfo,
-            @Nullable ClassLoader classLoader) {
+            @Nullable ClassLoader classLoader,
+            @Nullable List<ResourcesLoader> loaders) {
         try {
             Trace.traceBegin(Trace.TRACE_TAG_RESOURCES,
                     "ResourcesManager#createBaseActivityResources");
@@ -831,7 +735,8 @@
                     libDirs,
                     displayId,
                     overrideConfig != null ? new Configuration(overrideConfig) : null, // Copy
-                    compatInfo);
+                    compatInfo,
+                    loaders == null ? null : loaders.toArray(new ResourcesLoader[0]));
             classLoader = classLoader != null ? classLoader : ClassLoader.getSystemClassLoader();
 
             if (DEBUG) {
@@ -902,14 +807,6 @@
             } else {
                 ArrayUtils.unstableRemoveIf(mResourceReferences, sEmptyReferencePredicate);
             }
-
-            for (int index = mResourcesWithLoaders.size() - 1; index >= 0; index--) {
-                ResourcesWithLoaders resourcesWithLoaders = mResourcesWithLoaders.get(index);
-                Resources resources = resourcesWithLoaders.resources();
-                if (resources == null) {
-                    mResourcesWithLoaders.remove(index);
-                }
-            }
         }
     }
 
@@ -983,7 +880,8 @@
             int displayId,
             @Nullable Configuration overrideConfig,
             @NonNull CompatibilityInfo compatInfo,
-            @Nullable ClassLoader classLoader) {
+            @Nullable ClassLoader classLoader,
+            @Nullable List<ResourcesLoader> loaders) {
         try {
             Trace.traceBegin(Trace.TRACE_TAG_RESOURCES, "ResourcesManager#getResources");
             final ResourcesKey key = new ResourcesKey(
@@ -993,7 +891,8 @@
                     libDirs,
                     displayId,
                     overrideConfig != null ? new Configuration(overrideConfig) : null, // Copy
-                    compatInfo);
+                    compatInfo,
+                    loaders == null ? null : loaders.toArray(new ResourcesLoader[0]));
             classLoader = classLoader != null ? classLoader : ClassLoader.getSystemClassLoader();
 
             cleanupReferences(activityToken);
@@ -1010,10 +909,10 @@
 
     /**
      * Updates an Activity's Resources object with overrideConfig. The Resources object
-     * that was previously returned by
-     * {@link #getResources(IBinder, String, String[], String[], String[], int, Configuration,
-     * CompatibilityInfo, ClassLoader)} is
-     * still valid and will have the updated configuration.
+     * that was previously returned by {@link #getResources(IBinder, String, String[], String[],
+     * String[], int, Configuration, CompatibilityInfo, ClassLoader, List)} is still valid and will
+     * have the updated configuration.
+     *
      * @param activityToken The Activity token.
      * @param overrideConfig The configuration override to update.
      * @param displayId Id of the display where activity currently resides.
@@ -1074,25 +973,6 @@
                             overrideConfig, displayId);
                     updateActivityResources(resources, newKey, false);
                 }
-
-                // Also find loaders that are associated with an Activity
-                final int loaderCount = mResourcesWithLoaders.size();
-                for (int index = loaderCount - 1; index >= 0; index--) {
-                    ResourcesWithLoaders resourcesWithLoaders = mResourcesWithLoaders.get(
-                            index);
-                    Resources resources = resourcesWithLoaders.resources();
-                    if (resources == null
-                            || resourcesWithLoaders.activityToken() != activityToken) {
-                        continue;
-                    }
-
-                    ResourcesKey newKey = rebaseActivityOverrideConfig(resources, oldConfig,
-                            overrideConfig, displayId);
-
-                    updateActivityResources(resources, newKey, true);
-
-                    resourcesWithLoaders.updateKey(newKey);
-                }
             }
         } finally {
             Trace.traceEnd(Trace.TRACE_TAG_RESOURCES);
@@ -1133,9 +1013,8 @@
 
         // Create the new ResourcesKey with the rebased override config.
         final ResourcesKey newKey = new ResourcesKey(oldKey.mResDir,
-                oldKey.mSplitResDirs,
-                oldKey.mOverlayDirs, oldKey.mLibDirs, displayId,
-                rebasedOverrideConfig, oldKey.mCompatInfo);
+                oldKey.mSplitResDirs, oldKey.mOverlayDirs, oldKey.mLibDirs,
+                displayId, rebasedOverrideConfig, oldKey.mCompatInfo, oldKey.mLoaders);
 
         if (DEBUG) {
             Slog.d(TAG, "rebasing ref=" + resources + " from oldKey=" + oldKey
@@ -1214,18 +1093,6 @@
                 }
             }
 
-            for (int index = mResourcesWithLoaders.size() - 1; index >= 0; index--) {
-                ResourcesWithLoaders resourcesWithLoaders = mResourcesWithLoaders.get(index);
-                Resources resources = resourcesWithLoaders.resources();
-                if (resources == null) {
-                    mResourcesWithLoaders.remove(index);
-                    continue;
-                }
-
-                applyConfigurationToResourcesLocked(config, compat, tmpConfig,
-                        resourcesWithLoaders.resourcesKey(), resources.getImpl());
-            }
-
             return changes != 0;
         } finally {
             Trace.traceEnd(Trace.TRACE_TAG_RESOURCES);
@@ -1306,37 +1173,8 @@
                                 newLibAssets,
                                 key.mDisplayId,
                                 key.mOverrideConfiguration,
-                                key.mCompatInfo));
-                    }
-                }
-            }
-
-            final int count = mResourcesWithLoaders.size();
-            for (int index = 0; index < count; index++) {
-                ResourcesWithLoaders resourcesWithLoaders = mResourcesWithLoaders.get(index);
-                Resources resources = resourcesWithLoaders.resources();
-                if (resources == null) {
-                    continue;
-                }
-
-                ResourcesKey key = resourcesWithLoaders.resourcesKey();
-                if (Objects.equals(key.mResDir, assetPath)) {
-                    String[] newLibAssets = key.mLibDirs;
-                    for (String libAsset : libAssets) {
-                        newLibAssets =
-                                ArrayUtils.appendElement(String.class, newLibAssets, libAsset);
-                    }
-
-                    if (!Arrays.equals(newLibAssets, key.mLibDirs)) {
-                        updatedResourceKeys.put(resources.getImpl(),
-                                new ResourcesKey(
-                                        key.mResDir,
-                                        key.mSplitResDirs,
-                                        key.mOverlayDirs,
-                                        newLibAssets,
-                                        key.mDisplayId,
-                                        key.mOverrideConfiguration,
-                                        key.mCompatInfo));
+                                key.mCompatInfo,
+                                key.mLoaders));
                     }
                 }
             }
@@ -1345,72 +1183,6 @@
         }
     }
 
-    /**
-     * Mark a {@link Resources} as containing a {@link ResourceLoader}.
-     *
-     * This removes its {@link ResourcesImpl} from the shared pool and creates it a new one. It is
-     * then tracked separately, kept unique, and restored properly across {@link Activity}
-     * recreations.
-     */
-    public void registerForLoaders(Resources resources) {
-        synchronized (this) {
-            boolean found = false;
-            IBinder activityToken = null;
-
-            // Remove the Resources from the reference list as it's now tracked separately
-            int size = mResourceReferences.size();
-            for (int index = 0; index < size; index++) {
-                WeakReference<Resources> reference = mResourceReferences.get(index);
-                if (reference.get() == resources) {
-                    mResourceReferences.remove(index);
-                    found = true;
-                    break;
-                }
-            }
-
-            if (!found) {
-                // Do the same removal for any Activity Resources
-                for (Map.Entry<IBinder, ActivityResources> entry :
-                        mActivityResourceReferences.entrySet()) {
-                    ArrayList<WeakReference<Resources>> activityResourcesList =
-                            entry.getValue().activityResources;
-                    final int resCount = activityResourcesList.size();
-                    for (int index = 0; index < resCount; index++) {
-                        WeakReference<Resources> reference = activityResourcesList.get(index);
-                        if (reference.get() == resources) {
-                            activityToken = entry.getKey();
-                            activityResourcesList.remove(index);
-                            found = true;
-                            break;
-                        }
-                    }
-
-                    if (found) {
-                        break;
-                    }
-                }
-            }
-
-            if (!found) {
-                throw new IllegalArgumentException("Resources " + resources
-                        + " registered for loaders but was not previously tracked by"
-                        + " ResourcesManager");
-            }
-
-            ResourcesKey key = findKeyForResourceImplLocked(resources.getImpl());
-            ResourcesImpl impl = createResourcesImpl(key);
-
-            if (mResourcesWithLoaders == Collections.EMPTY_LIST) {
-                mResourcesWithLoaders = Collections.synchronizedList(new ArrayList<>());
-            }
-
-            mResourcesWithLoaders.add(new ResourcesWithLoaders(resources, key, activityToken));
-
-            // Set the new Impl, which is now guaranteed to be unique per Resources object
-            resources.setImpl(impl);
-        }
-    }
-
     // TODO(adamlesinski): Make this accept more than just overlay directories.
     final void applyNewResourceDirsLocked(@NonNull final ApplicationInfo appInfo,
             @Nullable final String[] oldPaths) {
@@ -1450,37 +1222,12 @@
                             key.mLibDirs,
                             key.mDisplayId,
                             key.mOverrideConfiguration,
-                            key.mCompatInfo
+                            key.mCompatInfo,
+                            key.mLoaders
                     ));
                 }
             }
 
-            final int count = mResourcesWithLoaders.size();
-            for (int index = 0; index < count; index++) {
-                ResourcesWithLoaders resourcesWithLoaders = mResourcesWithLoaders.get(index);
-                Resources resources = resourcesWithLoaders.resources();
-                if (resources == null) {
-                    continue;
-                }
-
-                ResourcesKey key = resourcesWithLoaders.resourcesKey();
-
-                if (key.mResDir == null
-                        || key.mResDir.equals(baseCodePath)
-                        || ArrayUtils.contains(oldPaths, key.mResDir)) {
-                    updatedResourceKeys.put(resources.getImpl(),
-                            new ResourcesKey(
-                                    baseCodePath,
-                                    copiedSplitDirs,
-                                    copiedResourceDirs,
-                                    key.mLibDirs,
-                                    key.mDisplayId,
-                                    key.mOverrideConfiguration,
-                                    key.mCompatInfo
-                            ));
-                }
-            }
-
             redirectResourcesToNewImplLocked(updatedResourceKeys);
         } finally {
             Trace.traceEnd(Trace.TRACE_TAG_RESOURCES);
@@ -1530,25 +1277,62 @@
                 }
             }
         }
+    }
 
-        // Update any references that need to be re-built with loaders. These are intentionally not
-        // part of either of the above lists.
-        final int loaderCount = mResourcesWithLoaders.size();
-        for (int index = loaderCount - 1; index >= 0; index--) {
-            ResourcesWithLoaders resourcesWithLoaders = mResourcesWithLoaders.get(index);
-            Resources resources = resourcesWithLoaders.resources();
-            if (resources == null) {
-                continue;
+    private class UpdateHandler implements Resources.UpdateCallbacks {
+
+        /**
+         * Updates the list of {@link ResourcesLoader ResourcesLoader(s)} that the {@code resources}
+         * instance uses.
+         */
+        @Override
+        public void onLoadersChanged(Resources resources, List<ResourcesLoader> newLoader) {
+            synchronized (ResourcesManager.this) {
+                final ResourcesKey oldKey = findKeyForResourceImplLocked(resources.getImpl());
+                if (oldKey == null) {
+                    throw new IllegalArgumentException("Cannot modify resource loaders of"
+                            + " ResourcesImpl not registered with ResourcesManager");
+                }
+
+                final ResourcesKey newKey = new ResourcesKey(
+                        oldKey.mResDir,
+                        oldKey.mSplitResDirs,
+                        oldKey.mOverlayDirs,
+                        oldKey.mLibDirs,
+                        oldKey.mDisplayId,
+                        oldKey.mOverrideConfiguration,
+                        oldKey.mCompatInfo,
+                        newLoader.toArray(new ResourcesLoader[0]));
+
+                final ResourcesImpl impl = findOrCreateResourcesImplForKeyLocked(newKey);
+                resources.setImpl(impl);
             }
+        }
 
-            ResourcesKey newKey = updatedResourceKeys.get(resources.getImpl());
-            if (newKey == null) {
-                continue;
+        /**
+         * Refreshes the {@link AssetManager} of all {@link ResourcesImpl} that contain the
+         * {@code loader} to apply any changes of the set of {@link ApkAssets}.
+         **/
+        @Override
+        public void onLoaderUpdated(ResourcesLoader loader) {
+            synchronized (ResourcesManager.this) {
+                final ArrayMap<ResourcesImpl, ResourcesKey> updatedResourceImplKeys =
+                        new ArrayMap<>();
+
+                for (int i = mResourceImpls.size() - 1; i >= 0; i--) {
+                    final ResourcesKey key = mResourceImpls.keyAt(i);
+                    final WeakReference<ResourcesImpl> impl = mResourceImpls.valueAt(i);
+                    if (impl == null || impl.get() == null
+                            || !ArrayUtils.contains(key.mLoaders, loader)) {
+                        continue;
+                    }
+
+                    mResourceImpls.remove(key);
+                    updatedResourceImplKeys.put(impl.get(), key);
+                }
+
+                redirectResourcesToNewImplLocked(updatedResourceImplKeys);
             }
-
-            resourcesWithLoaders.updateKey(newKey);
-            resourcesWithLoaders.resources()
-                    .setImpl(createResourcesImpl(newKey));
         }
     }
 }
diff --git a/core/java/android/content/pm/PackageParser.java b/core/java/android/content/pm/PackageParser.java
index fd4c265..906ca10 100644
--- a/core/java/android/content/pm/PackageParser.java
+++ b/core/java/android/content/pm/PackageParser.java
@@ -8519,7 +8519,8 @@
                 Display.DEFAULT_DISPLAY,
                 null,
                 systemResources.getCompatibilityInfo(),
-                systemResources.getClassLoader());
+                systemResources.getClassLoader(),
+                null);
 
         sUseRoundIcon = overlayableRes.getBoolean(com.android.internal.R.bool.config_useRoundIcon);
     }
diff --git a/core/java/android/content/res/AssetManager.java b/core/java/android/content/res/AssetManager.java
index 96fbe91..1b01758 100644
--- a/core/java/android/content/res/AssetManager.java
+++ b/core/java/android/content/res/AssetManager.java
@@ -27,13 +27,12 @@
 import android.compat.annotation.UnsupportedAppUsage;
 import android.content.pm.ActivityInfo;
 import android.content.res.Configuration.NativeConfig;
-import android.content.res.loader.ResourceLoader;
-import android.content.res.loader.ResourceLoaderManager;
+import android.content.res.loader.AssetsProvider;
+import android.content.res.loader.ResourcesLoader;
 import android.content.res.loader.ResourcesProvider;
 import android.os.ParcelFileDescriptor;
 import android.util.ArraySet;
 import android.util.Log;
-import android.util.Pair;
 import android.util.SparseArray;
 import android.util.TypedValue;
 
@@ -47,6 +46,7 @@
 import java.nio.file.Paths;
 import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Locale;
@@ -113,12 +113,7 @@
     @GuardedBy("this") private int mNumRefs = 1;
     @GuardedBy("this") private HashMap<Long, RuntimeException> mRefStacks;
 
-    private ResourceLoaderManager mResourceLoaderManager;
-
-    /** @hide */
-    public void setResourceLoaderManager(ResourceLoaderManager resourceLoaderManager) {
-        mResourceLoaderManager = resourceLoaderManager;
-    }
+    private ResourcesLoader[] mLoaders;
 
     /**
      * A Builder class that helps create an AssetManager with only a single invocation of
@@ -130,32 +125,66 @@
      */
     public static class Builder {
         private ArrayList<ApkAssets> mUserApkAssets = new ArrayList<>();
+        private ArrayList<ResourcesLoader> mLoaders = new ArrayList<>();
 
         public Builder addApkAssets(ApkAssets apkAssets) {
             mUserApkAssets.add(apkAssets);
             return this;
         }
 
+        public Builder addLoader(ResourcesLoader loader) {
+            mLoaders.add(loader);
+            return this;
+        }
+
         public AssetManager build() {
             // Retrieving the system ApkAssets forces their creation as well.
             final ApkAssets[] systemApkAssets = getSystem().getApkAssets();
 
-            final int totalApkAssetCount = systemApkAssets.length + mUserApkAssets.size();
+            // Filter ApkAssets so that assets provided by multiple loaders are only included once
+            // in the AssetManager assets. The last appearance of the ApkAssets dictates its load
+            // order.
+            final ArrayList<ApkAssets> loaderApkAssets = new ArrayList<>();
+            final ArraySet<ApkAssets> uniqueLoaderApkAssets = new ArraySet<>();
+            for (int i = mLoaders.size() - 1; i >= 0; i--) {
+                final List<ApkAssets> currentLoaderApkAssets = mLoaders.get(i).getApkAssets();
+                for (int j = currentLoaderApkAssets.size() - 1; j >= 0; j--) {
+                    final ApkAssets apkAssets = currentLoaderApkAssets.get(j);
+                    if (uniqueLoaderApkAssets.contains(apkAssets)) {
+                        continue;
+                    }
+
+                    uniqueLoaderApkAssets.add(apkAssets);
+                    loaderApkAssets.add(0, apkAssets);
+                }
+            }
+
+            final int totalApkAssetCount = systemApkAssets.length + mUserApkAssets.size()
+                    + loaderApkAssets.size();
             final ApkAssets[] apkAssets = new ApkAssets[totalApkAssetCount];
 
             System.arraycopy(systemApkAssets, 0, apkAssets, 0, systemApkAssets.length);
 
-            final int userApkAssetCount = mUserApkAssets.size();
-            for (int i = 0; i < userApkAssetCount; i++) {
+            // Append user ApkAssets after system ApkAssets.
+            for (int i = 0, n = mUserApkAssets.size(); i < n; i++) {
                 apkAssets[i + systemApkAssets.length] = mUserApkAssets.get(i);
             }
 
+            // Append ApkAssets provided by loaders to the end.
+            for (int i = 0, n = loaderApkAssets.size(); i < n; i++) {
+                apkAssets[i + systemApkAssets.length  + mUserApkAssets.size()] =
+                        loaderApkAssets.get(i);
+            }
+
             // Calling this constructor prevents creation of system ApkAssets, which we took care
             // of in this Builder.
             final AssetManager assetManager = new AssetManager(false /*sentinel*/);
             assetManager.mApkAssets = apkAssets;
             AssetManager.nativeSetApkAssets(assetManager.mObject, apkAssets,
                     false /*invalidateCaches*/);
+            assetManager.mLoaders = mLoaders.isEmpty() ? null
+                    : mLoaders.toArray(new ResourcesLoader[0]);
+
             return assetManager;
         }
     }
@@ -432,6 +461,12 @@
         }
     }
 
+    /** @hide */
+    @NonNull
+    public List<ResourcesLoader> getLoaders() {
+        return mLoaders == null ? Collections.emptyList() : Arrays.asList(mLoaders);
+    }
+
     /**
      * Ensures that the native implementation has not been destroyed.
      * The AssetManager may have been closed, but references to it still exist
@@ -1056,38 +1091,70 @@
         }
     }
 
-    private InputStream searchLoaders(int cookie, @NonNull String fileName, int accessMode)
-            throws IOException {
-        if (mResourceLoaderManager == null) {
+    private ResourcesProvider findResourcesProvider(int assetCookie) {
+        if (mLoaders == null) {
             return null;
         }
 
-        List<Pair<ResourceLoader, ResourcesProvider>> loaders =
-                mResourceLoaderManager.getInternalList();
+        int apkAssetsIndex = assetCookie - 1;
+        if (apkAssetsIndex >= mApkAssets.length || apkAssetsIndex < 0) {
+            return null;
+        }
 
-        // A cookie of 0 means no specific ApkAssets, so search everything
+        final ApkAssets apkAssets = mApkAssets[apkAssetsIndex];
+        if (!apkAssets.isForLoader()) {
+            return null;
+        }
+
+        for (int i = mLoaders.length - 1; i >= 0; i--) {
+            final ResourcesLoader loader = mLoaders[i];
+            for (int j = 0, n = loader.getProviders().size(); j < n; j++) {
+                final ResourcesProvider provider = loader.getProviders().get(j);
+                if (apkAssets == provider.getApkAssets()) {
+                    return provider;
+                }
+            }
+        }
+
+        return null;
+    }
+
+    private InputStream searchLoaders(int cookie, @NonNull String fileName, int accessMode)
+            throws IOException {
+        if (mLoaders == null) {
+            return null;
+        }
+
         if (cookie == 0) {
-            for (int index = loaders.size() - 1; index >= 0; index--) {
-                Pair<ResourceLoader, ResourcesProvider> pair = loaders.get(index);
-                try {
-                    InputStream inputStream = pair.first.loadAsset(fileName, accessMode);
-                    if (inputStream != null) {
-                        return inputStream;
+            // A cookie of 0 means no specific ApkAssets, so search everything
+            for (int i = mLoaders.length - 1; i >= 0; i--) {
+                final ResourcesLoader loader = mLoaders[i];
+                final List<ResourcesProvider> providers = loader.getProviders();
+                for (int j = providers.size() - 1; j >= 0; j--) {
+                    final AssetsProvider assetsProvider = providers.get(j).getAssetsProvider();
+                    if (assetsProvider == null) {
+                        continue;
                     }
-                } catch (IOException ignored) {
-                    // When searching, ignore read failures
+
+                    try {
+                        final InputStream inputStream = assetsProvider.loadAsset(
+                                fileName, accessMode);
+                        if (inputStream != null) {
+                            return inputStream;
+                        }
+                    } catch (IOException ignored) {
+                        // When searching, ignore read failures
+                    }
                 }
             }
 
             return null;
         }
 
-        ApkAssets apkAssets = mApkAssets[cookie - 1];
-        for (int index = loaders.size() - 1; index >= 0; index--) {
-            Pair<ResourceLoader, ResourcesProvider> pair = loaders.get(index);
-            if (pair.second.getApkAssets() == apkAssets) {
-                return pair.first.loadAsset(fileName, accessMode);
-            }
+        final ResourcesProvider provider = findResourcesProvider(cookie);
+        if (provider != null && provider.getAssetsProvider() != null) {
+            return provider.getAssetsProvider().loadAsset(
+                    fileName, accessMode);
         }
 
         return null;
@@ -1095,43 +1162,48 @@
 
     private AssetFileDescriptor searchLoadersFd(int cookie, @NonNull String fileName)
             throws IOException {
-        if (mResourceLoaderManager == null) {
+        if (mLoaders == null) {
             return null;
         }
 
-        List<Pair<ResourceLoader, ResourcesProvider>> loaders =
-                mResourceLoaderManager.getInternalList();
-
-        // A cookie of 0 means no specific ApkAssets, so search everything
         if (cookie == 0) {
-            for (int index = loaders.size() - 1; index >= 0; index--) {
-                Pair<ResourceLoader, ResourcesProvider> pair = loaders.get(index);
-                try {
-                    ParcelFileDescriptor fileDescriptor = pair.first.loadAssetFd(fileName);
-                    if (fileDescriptor != null) {
-                        return new AssetFileDescriptor(fileDescriptor, 0,
-                                AssetFileDescriptor.UNKNOWN_LENGTH);
+            // A cookie of 0 means no specific ApkAssets, so search everything
+            for (int i = mLoaders.length - 1; i >= 0; i--) {
+                final ResourcesLoader loader = mLoaders[i];
+                final List<ResourcesProvider> providers = loader.getProviders();
+                for (int j = providers.size() - 1; j >= 0; j--) {
+                    final AssetsProvider assetsProvider = providers.get(j).getAssetsProvider();
+                    if (assetsProvider == null) {
+                        continue;
                     }
-                } catch (IOException ignored) {
-                    // When searching, ignore read failures
+
+                    try {
+                        final ParcelFileDescriptor fileDescriptor = assetsProvider
+                                .loadAssetParcelFd(fileName);
+                        if (fileDescriptor != null) {
+                            return new AssetFileDescriptor(fileDescriptor, 0,
+                                    AssetFileDescriptor.UNKNOWN_LENGTH);
+                        }
+                    } catch (IOException ignored) {
+                        // When searching, ignore read failures
+                    }
                 }
             }
 
             return null;
         }
 
-        ApkAssets apkAssets = mApkAssets[cookie - 1];
-        for (int index = loaders.size() - 1; index >= 0; index--) {
-            Pair<ResourceLoader, ResourcesProvider> pair = loaders.get(index);
-            if (pair.second.getApkAssets() == apkAssets) {
-                ParcelFileDescriptor fileDescriptor = pair.first.loadAssetFd(fileName);
-                if (fileDescriptor != null) {
-                    return new AssetFileDescriptor(fileDescriptor, 0,
-                            AssetFileDescriptor.UNKNOWN_LENGTH);
-                }
-                return null;
+        final ResourcesProvider provider = findResourcesProvider(cookie);
+        if (provider != null && provider.getAssetsProvider() != null) {
+            final ParcelFileDescriptor fileDescriptor = provider.getAssetsProvider()
+                    .loadAssetParcelFd(fileName);
+            if (fileDescriptor != null) {
+                return new AssetFileDescriptor(fileDescriptor, 0,
+                        AssetFileDescriptor.UNKNOWN_LENGTH);
             }
+            return null;
         }
+
         return null;
     }
 
diff --git a/core/java/android/content/res/Resources.java b/core/java/android/content/res/Resources.java
index 4725e0a..471e83c 100644
--- a/core/java/android/content/res/Resources.java
+++ b/core/java/android/content/res/Resources.java
@@ -30,7 +30,6 @@
 import android.annotation.DrawableRes;
 import android.annotation.FontRes;
 import android.annotation.FractionRes;
-import android.annotation.IntRange;
 import android.annotation.IntegerRes;
 import android.annotation.LayoutRes;
 import android.annotation.NonNull;
@@ -41,13 +40,10 @@
 import android.annotation.StyleRes;
 import android.annotation.StyleableRes;
 import android.annotation.XmlRes;
-import android.app.ResourcesManager;
 import android.compat.annotation.UnsupportedAppUsage;
 import android.content.pm.ActivityInfo;
 import android.content.pm.ActivityInfo.Config;
-import android.content.res.loader.ResourceLoader;
-import android.content.res.loader.ResourceLoaderManager;
-import android.content.res.loader.ResourcesProvider;
+import android.content.res.loader.ResourcesLoader;
 import android.graphics.Movie;
 import android.graphics.Typeface;
 import android.graphics.drawable.Drawable;
@@ -55,18 +51,17 @@
 import android.graphics.drawable.DrawableInflater;
 import android.os.Build;
 import android.os.Bundle;
+import android.util.ArraySet;
 import android.util.AttributeSet;
 import android.util.DisplayMetrics;
 import android.util.Log;
 import android.util.LongSparseArray;
-import android.util.Pair;
 import android.util.Pools.SynchronizedPool;
 import android.util.TypedValue;
 import android.view.DisplayAdjustments;
 import android.view.ViewDebug;
 import android.view.ViewHierarchyEncoder;
 
-import com.android.internal.annotations.GuardedBy;
 import com.android.internal.annotations.VisibleForTesting;
 import com.android.internal.util.ArrayUtils;
 import com.android.internal.util.GrowingArrayUtils;
@@ -117,6 +112,7 @@
     static final String TAG = "Resources";
 
     private static final Object sSync = new Object();
+    private final Object mLock = new Object();
 
     // Used by BridgeResources in layoutlib
     @UnsupportedAppUsage
@@ -143,10 +139,7 @@
     @UnsupportedAppUsage
     final ClassLoader mClassLoader;
 
-    private final Object mResourceLoaderLock = new Object();
-
-    @GuardedBy("mResourceLoaderLock")
-    private ResourceLoaderManager mResourceLoaderManager;
+    private UpdateCallbacks mCallbacks = null;
 
     /**
      * WeakReferences to Themes that were constructed from this Resources object.
@@ -240,6 +233,18 @@
         }
     }
 
+    /** @hide */
+    public interface UpdateCallbacks extends ResourcesLoader.UpdateCallbacks {
+        /**
+         * Invoked when a {@link Resources} instance has a {@link ResourcesLoader} added, removed,
+         * or reordered.
+         *
+         * @param resources the instance being updated
+         * @param newLoaders the new set of loaders for the instance
+         */
+        void onLoadersChanged(Resources resources, List<ResourcesLoader> newLoaders);
+    }
+
     /**
      * Create a new Resources object on top of an existing set of assets in an
      * AssetManager.
@@ -303,12 +308,6 @@
         mBaseApkAssetsSize = ArrayUtils.size(impl.getAssets().getApkAssets());
         mResourcesImpl = impl;
 
-        synchronized (mResourceLoaderLock) {
-            if (mResourceLoaderManager != null) {
-                mResourceLoaderManager.onImplUpdate(mResourcesImpl);
-            }
-        }
-
         // Create new ThemeImpls that are identical to the ones we have.
         synchronized (mThemeRefs) {
             final int count = mThemeRefs.size();
@@ -322,6 +321,15 @@
         }
     }
 
+    /** @hide */
+    public void setCallbacks(UpdateCallbacks callbacks) {
+        if (mCallbacks != null) {
+            throw new IllegalStateException("callback already registered");
+        }
+
+        mCallbacks = callbacks;
+    }
+
     /**
      * @hide
      */
@@ -937,14 +945,6 @@
     @UnsupportedAppUsage
     Drawable loadDrawable(@NonNull TypedValue value, int id, int density, @Nullable Theme theme)
             throws NotFoundException {
-        ResourceLoader loader = findLoader(value.assetCookie);
-        if (loader != null) {
-            Drawable drawable = loader.loadDrawable(value, id, density, theme);
-            if (drawable != null) {
-                return drawable;
-            }
-        }
-
         return mResourcesImpl.loadDrawable(this, value, id, density, theme);
     }
 
@@ -2337,14 +2337,6 @@
     @UnsupportedAppUsage
     XmlResourceParser loadXmlResourceParser(String file, int id, int assetCookie,
                                             String type) throws NotFoundException {
-        ResourceLoader loader = findLoader(assetCookie);
-        if (loader != null) {
-            XmlResourceParser xml = loader.loadXmlResourceParser(file, id);
-            if (xml != null) {
-                return xml;
-            }
-        }
-
         return mResourcesImpl.loadXmlResourceParser(file, id, assetCookie, type);
     }
 
@@ -2371,136 +2363,106 @@
         return theme.obtainStyledAttributes(set, attrs, 0, 0);
     }
 
-    private ResourceLoader findLoader(int assetCookie) {
-        ApkAssets[] apkAssetsArray = mResourcesImpl.getAssets().getApkAssets();
-        int apkAssetsIndex = assetCookie - 1;
-        if (apkAssetsIndex < apkAssetsArray.length && apkAssetsIndex >= 0) {
-            ApkAssets apkAssets = apkAssetsArray[apkAssetsIndex];
-            if (apkAssets.isForLoader()) {
-                List<Pair<ResourceLoader, ResourcesProvider>> loaders;
-                // Since we don't lock the entire resolution path anyways,
-                // only lock here instead of entire method. The list is copied
-                // and effectively a snapshot is used.
-                synchronized (mResourceLoaderLock) {
-                    loaders = mResourceLoaderManager.getInternalList();
-                }
-
-                if (!ArrayUtils.isEmpty(loaders)) {
-                    int size = loaders.size();
-                    for (int index = 0; index < size; index++) {
-                        Pair<ResourceLoader, ResourcesProvider> pair = loaders.get(index);
-                        if (pair.second.getApkAssets() == apkAssets) {
-                            return pair.first;
-                        }
-                    }
-                }
-            }
+    private void checkCallbacksRegistered() {
+        if (mCallbacks == null) {
+            throw new IllegalArgumentException("Cannot modify resource loaders of Resources"
+                    + " instances created outside of ResourcesManager");
         }
-
-        return null;
     }
 
     /**
-     * @return copied list of loaders and providers previously added
+     * Retrieves the list of loaders.
+     *
+     * <p>Loaders are listed in increasing precedence order. A loader will override the resources
+     * and assets of loaders listed before itself.
      */
     @NonNull
-    public List<Pair<ResourceLoader, ResourcesProvider>> getLoaders() {
-        synchronized (mResourceLoaderLock) {
-            return mResourceLoaderManager == null
-                    ? Collections.emptyList()
-                    : mResourceLoaderManager.getLoaders();
-        }
+    public List<ResourcesLoader> getLoaders() {
+        return mResourcesImpl.getAssets().getLoaders();
     }
 
     /**
-     * Add a custom {@link ResourceLoader} which is added to the paths searched by
-     * {@link AssetManager} when resolving a resource.
+     * Appends a loader to the end of the loader list. If the loader is already present in the
+     * loader list, the list will not be modified.
      *
-     * Resources are resolved as if the loader was a resource overlay, meaning the latest
-     * in the list, of equal or better config, is returned.
-     *
-     * {@link ResourcesProvider}s passed in here are not managed and a reference should be held
-     * to remove, re-use, or close them when necessary.
-     *
-     * @param resourceLoader an interface used to resolve file paths for drawables/XML files;
-     *                       a reference should be kept to remove the loader if necessary
-     * @param resourcesProvider an .apk or .arsc file representation
-     * @param index where to add the loader in the list
-     * @throws IllegalArgumentException if the resourceLoader is already added
-     * @throws IndexOutOfBoundsException if the index is invalid
+     * @param loader the loader to add
      */
-    public void addLoader(@NonNull ResourceLoader resourceLoader,
-            @NonNull ResourcesProvider resourcesProvider, @IntRange(from = 0) int index) {
-        synchronized (mResourceLoaderLock) {
-            if (mResourceLoaderManager == null) {
-                ResourcesManager.getInstance().registerForLoaders(this);
-                mResourceLoaderManager = new ResourceLoaderManager(mResourcesImpl);
+    public void addLoader(@NonNull ResourcesLoader loader) {
+        synchronized (mLock) {
+            checkCallbacksRegistered();
+
+            final List<ResourcesLoader> loaders = new ArrayList<>(
+                    mResourcesImpl.getAssets().getLoaders());
+            if (loaders.contains(loader)) {
+                return;
             }
 
-            mResourceLoaderManager.addLoader(resourceLoader, resourcesProvider, index);
+            loaders.add(loader);
+            mCallbacks.onLoadersChanged(this, loaders);
+            loader.registerOnProvidersChangedCallback(this, mCallbacks);
         }
     }
 
     /**
-     * @see #addLoader(ResourceLoader, ResourcesProvider, int).
+     * Removes a loader from the loaders. If the loader is not present in the loader list, the list
+     * will not be modified.
      *
-     * Adds to the end of the list.
-     *
-     * @return index the loader was added at
+     * @param loader the loader to remove
      */
-    public int addLoader(@NonNull ResourceLoader resourceLoader,
-            @NonNull ResourcesProvider resourcesProvider) {
-        synchronized (mResourceLoaderLock) {
-            int index = getLoaders().size();
-            addLoader(resourceLoader, resourcesProvider, index);
-            return index;
-        }
-    }
+    public void removeLoader(@NonNull ResourcesLoader loader) {
+        synchronized (mLock) {
+            checkCallbacksRegistered();
 
-    /**
-     * Remove a loader previously added by
-     * {@link #addLoader(ResourceLoader, ResourcesProvider, int)}
-     *
-     * The caller maintains responsibility for holding a reference to the matching
-     * {@link ResourcesProvider} and closing it after this method has been called.
-     *
-     * @param resourceLoader the same reference passed into [addLoader
-     * @return the index the loader was at in the list, or -1 if the loader was not found
-     */
-    public int removeLoader(@NonNull ResourceLoader resourceLoader) {
-        synchronized (mResourceLoaderLock) {
-            if (mResourceLoaderManager == null) {
-                return -1;
+            final List<ResourcesLoader> loaders = new ArrayList<>(
+                    mResourcesImpl.getAssets().getLoaders());
+            if (!loaders.remove(loader)) {
+                return;
             }
 
-            return mResourceLoaderManager.removeLoader(resourceLoader);
+            mCallbacks.onLoadersChanged(this, loaders);
+            loader.unregisterOnProvidersChangedCallback(this);
         }
     }
 
     /**
-     * Swap the current set of loaders. Preferred to multiple remove/add calls as this doesn't
-     * update the resource data structures after each modification.
+     * Sets the list of loaders.
      *
-     * Set to null or an empty list to clear the set of loaders.
-     *
-     * The caller maintains responsibility for holding references to the added
-     * {@link ResourcesProvider}s and closing them after this method has been called.
-     *
-     * @param resourceLoadersAndProviders a list of pairs to add
+     * @param loaders the new loaders
      */
-    public void setLoaders(
-            @Nullable List<Pair<ResourceLoader, ResourcesProvider>> resourceLoadersAndProviders) {
-        synchronized (mResourceLoaderLock) {
-            if (mResourceLoaderManager == null) {
-                if (ArrayUtils.isEmpty(resourceLoadersAndProviders)) {
-                    return;
+    public void setLoaders(@NonNull List<ResourcesLoader> loaders) {
+        synchronized (mLock) {
+            checkCallbacksRegistered();
+
+            final List<ResourcesLoader> oldLoaders = mResourcesImpl.getAssets().getLoaders();
+            int index = 0;
+            boolean modified = loaders.size() != oldLoaders.size();
+            final ArraySet<ResourcesLoader> seenLoaders = new ArraySet<>();
+            for (final ResourcesLoader loader : loaders) {
+                if (!seenLoaders.add(loader)) {
+                    throw new IllegalArgumentException("Loader " + loader + " present twice");
                 }
 
-                ResourcesManager.getInstance().registerForLoaders(this);
-                mResourceLoaderManager = new ResourceLoaderManager(mResourcesImpl);
+                if (!modified && oldLoaders.get(index++) != loader) {
+                    modified = true;
+                }
             }
 
-            mResourceLoaderManager.setLoaders(resourceLoadersAndProviders);
+            if (!modified) {
+                return;
+            }
+
+            mCallbacks.onLoadersChanged(this, loaders);
+            for (int i = 0, n = oldLoaders.size(); i < n; i++) {
+                oldLoaders.get(i).unregisterOnProvidersChangedCallback(this);
+            }
+            for (ResourcesLoader newLoader : loaders) {
+                newLoader.registerOnProvidersChangedCallback(this, mCallbacks);
+            }
         }
     }
+
+    /** Removes all {@link ResourcesLoader ResourcesLoader(s)}. */
+    public void clearLoaders() {
+        setLoaders(Collections.emptyList());
+    }
 }
diff --git a/core/java/android/content/res/ResourcesKey.java b/core/java/android/content/res/ResourcesKey.java
index a29fea0..9e40f46 100644
--- a/core/java/android/content/res/ResourcesKey.java
+++ b/core/java/android/content/res/ResourcesKey.java
@@ -19,6 +19,7 @@
 import android.annotation.NonNull;
 import android.annotation.Nullable;
 import android.compat.annotation.UnsupportedAppUsage;
+import android.content.res.loader.ResourcesLoader;
 import android.text.TextUtils;
 
 import java.util.Arrays;
@@ -48,6 +49,9 @@
     @NonNull
     public final CompatibilityInfo mCompatInfo;
 
+    @Nullable
+    public final ResourcesLoader[] mLoaders;
+
     private final int mHash;
 
     @UnsupportedAppUsage
@@ -57,11 +61,13 @@
                         @Nullable String[] libDirs,
                         int displayId,
                         @Nullable Configuration overrideConfig,
-                        @Nullable CompatibilityInfo compatInfo) {
+                        @Nullable CompatibilityInfo compatInfo,
+                        @Nullable ResourcesLoader[] loader) {
         mResDir = resDir;
         mSplitResDirs = splitResDirs;
         mOverlayDirs = overlayDirs;
         mLibDirs = libDirs;
+        mLoaders = (loader != null && loader.length == 0) ? null : loader;
         mDisplayId = displayId;
         mOverrideConfiguration = new Configuration(overrideConfig != null
                 ? overrideConfig : Configuration.EMPTY);
@@ -75,6 +81,7 @@
         hash = 31 * hash + mDisplayId;
         hash = 31 * hash + Objects.hashCode(mOverrideConfiguration);
         hash = 31 * hash + Objects.hashCode(mCompatInfo);
+        hash = 31 * hash + Arrays.hashCode(mLoaders);
         mHash = hash;
     }
 
@@ -140,6 +147,9 @@
         if (!Objects.equals(mCompatInfo, peer.mCompatInfo)) {
             return false;
         }
+        if (!Arrays.equals(mLoaders, peer.mLoaders)) {
+            return false;
+        }
         return true;
     }
 
@@ -167,7 +177,11 @@
         builder.append(" mOverrideConfig=").append(Configuration.resourceQualifierString(
                 mOverrideConfiguration));
         builder.append(" mCompatInfo=").append(mCompatInfo);
-        builder.append("}");
+        builder.append(" mLoaders=[");
+        if (mLoaders != null) {
+            builder.append(TextUtils.join(",", mLoaders));
+        }
+        builder.append("]}");
         return builder.toString();
     }
 }
diff --git a/core/java/android/content/res/loader/AssetsProvider.java b/core/java/android/content/res/loader/AssetsProvider.java
new file mode 100644
index 0000000..c315494
--- /dev/null
+++ b/core/java/android/content/res/loader/AssetsProvider.java
@@ -0,0 +1,68 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.content.res.loader;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.content.res.AssetManager;
+import android.os.ParcelFileDescriptor;
+
+import java.io.IOException;
+import java.io.InputStream;
+
+/**
+ * Provides callbacks that allow for the value of a file-based resources or assets of a
+ * {@link ResourcesProvider} to be specified or overridden.
+ */
+public interface AssetsProvider {
+
+    /**
+     * Callback that allows the value of a file-based resources or asset to be specified or
+     * overridden.
+     *
+     * <p>There are two situations in which this method will be called:
+     * <ul>
+     * <li>AssetManager is queried for an InputStream of an asset using APIs like
+     * {@link AssetManager#open} and {@link AssetManager#openXmlResourceParser}.
+     * <li>AssetManager is resolving the value of a file-based resource provided by the
+     * {@link ResourcesProvider} this instance is associated with.
+     * </ul>
+     *
+     * <p>If the value retrieved from this callback is null, AssetManager will attempt to find the
+     * file-based resource or asset within the APK provided by the ResourcesProvider this instance
+     * is associated with.
+     *
+     * @param path the asset path being loaded
+     * @param accessMode the {@link AssetManager} access mode
+     *
+     * @see AssetManager#open
+     */
+    @Nullable
+    default InputStream loadAsset(@NonNull String path, int accessMode) throws IOException {
+        return null;
+    }
+
+    /**
+     * {@link ParcelFileDescriptor} variant of {@link #loadAsset(String, int)}.
+     *
+     * @param path the asset path being loaded
+     */
+    @Nullable
+    default ParcelFileDescriptor loadAssetParcelFd(@NonNull String path) throws IOException {
+        return null;
+    }
+}
diff --git a/core/java/android/content/res/loader/DirectoryResourceLoader.java b/core/java/android/content/res/loader/DirectoryAssetsProvider.java
similarity index 70%
rename from core/java/android/content/res/loader/DirectoryResourceLoader.java
rename to core/java/android/content/res/loader/DirectoryAssetsProvider.java
index 7d90e72..81c2a4c 100644
--- a/core/java/android/content/res/loader/DirectoryResourceLoader.java
+++ b/core/java/android/content/res/loader/DirectoryAssetsProvider.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2019 The Android Open Source Project
+ * Copyright (C) 2020 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -26,23 +26,27 @@
 import java.io.InputStream;
 
 /**
- * A {@link ResourceLoader} that searches a directory for assets.
- *
- * Assumes that resource paths are resolvable child paths of the directory passed in.
+ * A {@link AssetsProvider} that searches a directory for assets.
+ * Assumes that resource paths are resolvable child paths of the root directory passed in.
  */
-public class DirectoryResourceLoader implements ResourceLoader {
+public class DirectoryAssetsProvider implements AssetsProvider {
 
     @NonNull
     private final File mDirectory;
 
-    public DirectoryResourceLoader(@NonNull File directory) {
+    /**
+     * Creates a DirectoryAssetsProvider with given root directory.
+     *
+     * @param directory the root directory to resolve files from
+     */
+    public DirectoryAssetsProvider(@NonNull File directory) {
         this.mDirectory = directory;
     }
 
     @Nullable
     @Override
     public InputStream loadAsset(@NonNull String path, int accessMode) throws IOException {
-        File file = findFile(path);
+        final File file = findFile(path);
         if (file == null || !file.exists()) {
             return null;
         }
@@ -51,8 +55,8 @@
 
     @Nullable
     @Override
-    public ParcelFileDescriptor loadAssetFd(@NonNull String path) throws IOException {
-        File file = findFile(path);
+    public ParcelFileDescriptor loadAssetParcelFd(@NonNull String path) throws IOException {
+        final File file = findFile(path);
         if (file == null || !file.exists()) {
             return null;
         }
@@ -60,7 +64,9 @@
     }
 
     /**
-     * Find the file for the given path encoded into the resource table.
+     * Finds the file relative to the root directory.
+     *
+     * @param path the relative path of the file
      */
     @Nullable
     public File findFile(@NonNull String path) {
diff --git a/core/java/android/content/res/loader/ResourceLoader.java b/core/java/android/content/res/loader/ResourceLoader.java
deleted file mode 100644
index af32aa2..0000000
--- a/core/java/android/content/res/loader/ResourceLoader.java
+++ /dev/null
@@ -1,116 +0,0 @@
-/*
- * Copyright (C) 2019 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package android.content.res.loader;
-
-import android.annotation.AnyRes;
-import android.annotation.NonNull;
-import android.annotation.Nullable;
-import android.content.res.AssetManager;
-import android.content.res.Resources;
-import android.content.res.XmlResourceParser;
-import android.graphics.drawable.Drawable;
-import android.os.ParcelFileDescriptor;
-import android.util.TypedValue;
-
-import java.io.IOException;
-import java.io.InputStream;
-
-/**
- * Exposes methods for overriding file-based resource loading from a {@link Resources}.
- *
- * To be used with {@link Resources#addLoader(ResourceLoader, ResourcesProvider, int)} and related
- * methods to override resource loading.
- *
- * Note that this class doesn't actually contain any resource data. Non-file-based resources are
- * loaded directly from the {@link ResourcesProvider}'s .arsc representation.
- *
- * An instance's methods will only be called if its corresponding {@link ResourcesProvider}'s
- * resources table contains an entry for the resource ID being resolved,
- * with the exception of the non-cookie variants of {@link AssetManager}'s openAsset and
- * openNonAsset.
- *
- * Those methods search backwards through all {@link ResourceLoader}s and then any paths provided
- * by the application or system.
- *
- * Otherwise, an ARSC that defines R.drawable.some_id must be provided if a {@link ResourceLoader}
- * wants to point R.drawable.some_id to a different file on disk.
- */
-public interface ResourceLoader {
-
-    /**
-     * Given the value resolved from the string pool of the {@link ResourcesProvider} passed to
-     * {@link Resources#addLoader(ResourceLoader, ResourcesProvider, int)}, return a
-     * {@link Drawable} which should be returned by the parent
-     * {@link Resources#getDrawable(int, Resources.Theme)}.
-     *
-     * @param value   the resolved {@link TypedValue} before it has been converted to a Drawable
-     *                object
-     * @param id      the R.drawable ID this resolution is for
-     * @param density the requested density
-     * @param theme   the {@link Resources.Theme} resolved under
-     * @return null if resolution should try to find an entry inside the {@link ResourcesProvider},
-     * including calling through to {@link #loadAsset(String, int)} or {@link #loadAssetFd(String)}
-     */
-    @Nullable
-    default Drawable loadDrawable(@NonNull TypedValue value, int id, int density,
-            @Nullable Resources.Theme theme) {
-        return null;
-    }
-
-    /**
-     * Given the value resolved from the string pool of the {@link ResourcesProvider} passed to
-     * {@link Resources#addLoader(ResourceLoader, ResourcesProvider, int)}, return an
-     * {@link XmlResourceParser} which should be returned by the parent
-     * {@link Resources#getDrawable(int, Resources.Theme)}.
-     *
-     * @param path the string that was found in the string pool
-     * @param id   the XML ID this resolution is for, can be R.anim, R.layout, or R.xml
-     * @return null if resolution should try to find an entry inside the {@link ResourcesProvider},
-     * including calling through to {@link #loadAssetFd(String)} (String, int)}
-     */
-    @Nullable
-    default XmlResourceParser loadXmlResourceParser(@NonNull String path, @AnyRes int id) {
-        return null;
-    }
-
-    /**
-     * Given the value resolved from the string pool of the {@link ResourcesProvider} passed to
-     * {@link Resources#addLoader(ResourceLoader, ResourcesProvider, int)}, return an
-     * {@link InputStream} which should be returned when an asset is loaded by {@link AssetManager}.
-     * Assets will be loaded from a provider's root, with anything in its assets subpath prefixed
-     * with "assets/".
-     *
-     * @param path       the asset path to load
-     * @param accessMode {@link AssetManager} access mode; does not have to be respected
-     * @return null if resolution should try to find an entry inside the {@link ResourcesProvider}
-     */
-    @Nullable
-    default InputStream loadAsset(@NonNull String path, int accessMode) throws IOException {
-        return null;
-    }
-
-    /**
-     * {@link ParcelFileDescriptor} variant of {@link #loadAsset(String, int)}.
-     *
-     * @param path the asset path to load
-     * @return null if resolution should try to find an entry inside the {@link ResourcesProvider}
-     */
-    @Nullable
-    default ParcelFileDescriptor loadAssetFd(@NonNull String path) throws IOException {
-        return null;
-    }
-}
diff --git a/core/java/android/content/res/loader/ResourceLoaderManager.java b/core/java/android/content/res/loader/ResourceLoaderManager.java
deleted file mode 100644
index 592ec09..0000000
--- a/core/java/android/content/res/loader/ResourceLoaderManager.java
+++ /dev/null
@@ -1,190 +0,0 @@
-/*
- * Copyright (C) 2019 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package android.content.res.loader;
-
-import android.annotation.Nullable;
-import android.content.res.ApkAssets;
-import android.content.res.AssetManager;
-import android.content.res.Resources;
-import android.content.res.ResourcesImpl;
-import android.util.Pair;
-
-import com.android.internal.annotations.GuardedBy;
-import com.android.internal.util.ArrayUtils;
-
-import java.util.ArrayList;
-import java.util.List;
-import java.util.Objects;
-
-/**
- * @hide
- */
-public class ResourceLoaderManager {
-
-    private final Object mLock = new Object();
-
-    @GuardedBy("mLock")
-    private final List<Pair<ResourceLoader, ResourcesProvider>> mResourceLoaders =
-            new ArrayList<>();
-
-    @GuardedBy("mLock")
-    private ResourcesImpl mResourcesImpl;
-
-    public ResourceLoaderManager(ResourcesImpl resourcesImpl) {
-        this.mResourcesImpl = resourcesImpl;
-        this.mResourcesImpl.getAssets().setResourceLoaderManager(this);
-    }
-
-    /**
-     * Copies the list to ensure that ongoing mutations don't affect the list if it's being used
-     * as a search set.
-     *
-     * @see Resources#getLoaders()
-     */
-    public List<Pair<ResourceLoader, ResourcesProvider>> getLoaders() {
-        synchronized (mLock) {
-            return new ArrayList<>(mResourceLoaders);
-        }
-    }
-
-    /**
-     * Returns a list for searching for a loader. Locks and copies the list to ensure that
-     * ongoing mutations don't affect the search set.
-     */
-    public List<Pair<ResourceLoader, ResourcesProvider>> getInternalList() {
-        synchronized (mLock) {
-            return new ArrayList<>(mResourceLoaders);
-        }
-    }
-
-    /**
-     * TODO(b/136251855): Consider optional boolean ignoreConfigurations to allow ResourceLoader
-     * to override every configuration in the target package
-     *
-     * @see Resources#addLoader(ResourceLoader, ResourcesProvider)
-     */
-    public void addLoader(ResourceLoader resourceLoader, ResourcesProvider resourcesProvider,
-            int index) {
-        synchronized (mLock) {
-            for (int listIndex = 0; listIndex < mResourceLoaders.size(); listIndex++) {
-                if (Objects.equals(mResourceLoaders.get(listIndex).first, resourceLoader)) {
-                    throw new IllegalArgumentException("Cannot add the same ResourceLoader twice");
-                }
-            }
-
-            mResourceLoaders.add(index, Pair.create(resourceLoader, resourcesProvider));
-            updateLoaders();
-        }
-    }
-
-    /**
-     * @see Resources#removeLoader(ResourceLoader)
-     */
-    public int removeLoader(ResourceLoader resourceLoader) {
-        synchronized (mLock) {
-            int indexOfLoader = -1;
-
-            for (int index = 0; index < mResourceLoaders.size(); index++) {
-                if (mResourceLoaders.get(index).first == resourceLoader) {
-                    indexOfLoader = index;
-                    break;
-                }
-            }
-
-            if (indexOfLoader < 0) {
-                return indexOfLoader;
-            }
-
-            mResourceLoaders.remove(indexOfLoader);
-            updateLoaders();
-            return indexOfLoader;
-        }
-    }
-
-    /**
-     * @see Resources#setLoaders(List)
-     */
-    public void setLoaders(
-            @Nullable List<Pair<ResourceLoader, ResourcesProvider>> newLoadersAndProviders) {
-        synchronized (mLock) {
-            if (ArrayUtils.isEmpty(newLoadersAndProviders)) {
-                mResourceLoaders.clear();
-                updateLoaders();
-                return;
-            }
-
-            int size = newLoadersAndProviders.size();
-            for (int newIndex = 0; newIndex < size; newIndex++) {
-                ResourceLoader resourceLoader = newLoadersAndProviders.get(newIndex).first;
-                for (int oldIndex = 0; oldIndex < mResourceLoaders.size(); oldIndex++) {
-                    if (Objects.equals(mResourceLoaders.get(oldIndex).first, resourceLoader)) {
-                        throw new IllegalArgumentException(
-                                "Cannot add the same ResourceLoader twice");
-                    }
-                }
-            }
-
-            mResourceLoaders.clear();
-            mResourceLoaders.addAll(newLoadersAndProviders);
-
-            updateLoaders();
-        }
-    }
-
-    /**
-     * Swap the tracked {@link ResourcesImpl} and reattach any loaders to it.
-     */
-    public void onImplUpdate(ResourcesImpl resourcesImpl) {
-        synchronized (mLock) {
-            this.mResourcesImpl = resourcesImpl;
-            this.mResourcesImpl.getAssets().setResourceLoaderManager(this);
-            updateLoaders();
-        }
-    }
-
-    private void updateLoaders() {
-        synchronized (mLock) {
-            AssetManager assetManager = mResourcesImpl.getAssets();
-            ApkAssets[] existingApkAssets = assetManager.getApkAssets();
-            int baseApkAssetsSize = 0;
-            for (int index = existingApkAssets.length - 1; index >= 0; index--) {
-                // Loaders are always last, so the first non-loader is the end of the base assets
-                if (!existingApkAssets[index].isForLoader()) {
-                    baseApkAssetsSize = index + 1;
-                    break;
-                }
-            }
-
-            List<ApkAssets> newAssets = new ArrayList<>();
-            for (int index = 0; index < baseApkAssetsSize; index++) {
-                newAssets.add(existingApkAssets[index]);
-            }
-
-            int size = mResourceLoaders.size();
-            for (int index = 0; index < size; index++) {
-                ApkAssets apkAssets = mResourceLoaders.get(index).second.getApkAssets();
-                newAssets.add(apkAssets);
-            }
-
-            assetManager.setApkAssets(newAssets.toArray(new ApkAssets[0]), true);
-
-            // Short of resolving every resource, it's too difficult to determine what has changed
-            // when a resource loader is changed, so just clear everything.
-            mResourcesImpl.clearAllCaches();
-        }
-    }
-}
diff --git a/core/java/android/content/res/loader/ResourcesLoader.java b/core/java/android/content/res/loader/ResourcesLoader.java
new file mode 100644
index 0000000..69dacee
--- /dev/null
+++ b/core/java/android/content/res/loader/ResourcesLoader.java
@@ -0,0 +1,253 @@
+/*
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.content.res.loader;
+
+import android.annotation.NonNull;
+import android.content.res.ApkAssets;
+import android.content.res.Resources;
+import android.util.ArrayMap;
+import android.util.ArraySet;
+
+import com.android.internal.annotations.GuardedBy;
+import com.android.internal.util.ArrayUtils;
+
+import java.lang.ref.WeakReference;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+
+/**
+ * A container for supplying {@link ResourcesProvider ResourcesProvider(s)} to {@link Resources}
+ * objects.
+ *
+ * <p>{@link ResourcesLoader ResourcesLoader(s)} are added to Resources objects to supply
+ * additional resources and assets or modify the values of existing resources and assets. Multiple
+ * Resources objects can share the same ResourcesLoaders and ResourcesProviders. Changes to the list
+ * of {@link ResourcesProvider ResourcesProvider(s)} a loader contains propagates to all Resources
+ * objects that use the loader.
+ *
+ * <p>Loaders retrieved with {@link Resources#getLoaders()} are listed in increasing precedence
+ * order. A loader will override the resources and assets of loaders listed before itself.
+ *
+ * <p>Providers retrieved with {@link #getProviders()} are listed in increasing precedence order. A
+ * provider will override the resources and assets of providers listed before itself.
+ */
+public class ResourcesLoader {
+    private final Object mLock = new Object();
+
+    @GuardedBy("mLock")
+    private ApkAssets[] mApkAssets;
+
+    @GuardedBy("mLock")
+    private ResourcesProvider[] mPreviousProviders;
+
+    @GuardedBy("mLock")
+    private ResourcesProvider[] mProviders;
+
+    @GuardedBy("mLock")
+    private ArrayMap<WeakReference<Object>, UpdateCallbacks> mChangeCallbacks = new ArrayMap<>();
+
+    /** @hide */
+    public interface UpdateCallbacks {
+
+        /**
+         * Invoked when a {@link ResourcesLoader} has a {@link ResourcesProvider} added, removed,
+         * or reordered.
+         *
+         * @param loader the loader that was updated
+         */
+        void onLoaderUpdated(@NonNull ResourcesLoader loader);
+    }
+
+    /**
+     * Retrieves the list of providers loaded into this instance. Providers are listed in increasing
+     * precedence order. A provider will override the values of providers listed before itself.
+     */
+    @NonNull
+    public List<ResourcesProvider> getProviders() {
+        synchronized (mLock) {
+            return mProviders == null ? Collections.emptyList() : Arrays.asList(mProviders);
+        }
+    }
+
+    /**
+     * Appends a provider to the end of the provider list. If the provider is already present in the
+     * loader list, the list will not be modified.
+     *
+     * @param resourcesProvider the provider to add
+     */
+    public void addProvider(@NonNull ResourcesProvider resourcesProvider) {
+        synchronized (mLock) {
+            mProviders = ArrayUtils.appendElement(ResourcesProvider.class, mProviders,
+                    resourcesProvider);
+            notifyProvidersChangedLocked();
+        }
+    }
+
+    /**
+     * Removes a provider from the provider list. If the provider is not present in the provider
+     * list, the list will not be modified.
+     *
+     * @param resourcesProvider the provider to remove
+     */
+    public void removeProvider(@NonNull ResourcesProvider resourcesProvider) {
+        synchronized (mLock) {
+            mProviders = ArrayUtils.removeElement(ResourcesProvider.class, mProviders,
+                    resourcesProvider);
+            notifyProvidersChangedLocked();
+        }
+    }
+
+    /**
+     * Sets the list of providers.
+     *
+     * @param resourcesProviders the new providers
+     */
+    public void setProviders(@NonNull List<ResourcesProvider> resourcesProviders) {
+        synchronized (mLock) {
+            mProviders = resourcesProviders.toArray(new ResourcesProvider[0]);
+            notifyProvidersChangedLocked();
+        }
+    }
+
+    /** Removes all {@link ResourcesProvider ResourcesProvider(s)}. */
+    public void clearProviders() {
+        synchronized (mLock) {
+            mProviders = null;
+            notifyProvidersChangedLocked();
+        }
+    }
+
+    /**
+     * Retrieves the list of {@link ApkAssets} used by the providers.
+     *
+     * @hide
+     */
+    @NonNull
+    public List<ApkAssets> getApkAssets() {
+        synchronized (mLock) {
+            if (mApkAssets == null) {
+                return Collections.emptyList();
+            }
+            return Arrays.asList(mApkAssets);
+        }
+    }
+
+    /**
+     * Registers a callback to be invoked when {@link ResourcesProvider ResourcesProvider(s)}
+     * change.
+     * @param instance the instance tied to the callback
+     * @param callbacks the callback to invoke
+     *
+     * @hide
+     */
+    public void registerOnProvidersChangedCallback(@NonNull Object instance,
+            @NonNull UpdateCallbacks callbacks) {
+        synchronized (mLock) {
+            mChangeCallbacks.put(new WeakReference<>(instance), callbacks);
+        }
+    }
+
+    /**
+     * Removes a previously registered callback.
+     * @param instance the instance tied to the callback
+     *
+     * @hide
+     */
+    public void unregisterOnProvidersChangedCallback(@NonNull Object instance) {
+        synchronized (mLock) {
+            for (int i = 0, n = mChangeCallbacks.size(); i < n; i++) {
+                final WeakReference<Object> key = mChangeCallbacks.keyAt(i);
+                if (instance == key.get()) {
+                    mChangeCallbacks.removeAt(i);
+                    return;
+                }
+            }
+        }
+    }
+
+    /** Returns whether the arrays contain the same provider instances in the same order. */
+    private static boolean arrayEquals(ResourcesProvider[] a1, ResourcesProvider[] a2) {
+        if (a1 == a2) {
+            return true;
+        }
+
+        if (a1 == null || a2 == null) {
+            return false;
+        }
+
+        if (a1.length != a2.length) {
+            return false;
+        }
+
+        // Check that the arrays contain the exact same instances in the same order. Providers do
+        // not have any form of equivalence checking of whether the contents of two providers have
+        // equivalent apk assets.
+        for (int i = 0, n = a1.length; i < n; i++) {
+            if (a1[i] != a2[i]) {
+                return false;
+            }
+        }
+
+        return true;
+    }
+
+
+    /**
+     * Invokes registered callbacks when the list of {@link ResourcesProvider} instances this loader
+     * uses changes.
+     */
+    private void notifyProvidersChangedLocked() {
+        final ArraySet<UpdateCallbacks> uniqueCallbacks = new ArraySet<>();
+        if (arrayEquals(mPreviousProviders, mProviders)) {
+            return;
+        }
+
+        if (mProviders == null || mProviders.length == 0) {
+            mApkAssets = null;
+        } else {
+            mApkAssets = new ApkAssets[mProviders.length];
+            for (int i = 0, n = mProviders.length; i < n; i++) {
+                mProviders[i].incrementRefCount();
+                mApkAssets[i] = mProviders[i].getApkAssets();
+            }
+        }
+
+        // Decrement the ref count after incrementing the new provider ref count so providers
+        // present before and after this method do not drop to zero references.
+        if (mPreviousProviders != null) {
+            for (ResourcesProvider provider : mPreviousProviders) {
+                provider.decrementRefCount();
+            }
+        }
+
+        mPreviousProviders = mProviders;
+
+        for (int i = mChangeCallbacks.size() - 1; i >= 0; i--) {
+            final WeakReference<Object> key = mChangeCallbacks.keyAt(i);
+            if (key.get() == null) {
+                mChangeCallbacks.removeAt(i);
+            } else {
+                uniqueCallbacks.add(mChangeCallbacks.valueAt(i));
+            }
+        }
+
+        for (int i = 0, n = uniqueCallbacks.size(); i < n; i++) {
+            uniqueCallbacks.valueAt(i).onLoaderUpdated(this);
+        }
+    }
+}
diff --git a/core/java/android/content/res/loader/ResourcesProvider.java b/core/java/android/content/res/loader/ResourcesProvider.java
index 050aeb7..419ec78 100644
--- a/core/java/android/content/res/loader/ResourcesProvider.java
+++ b/core/java/android/content/res/loader/ResourcesProvider.java
@@ -17,84 +17,144 @@
 package android.content.res.loader;
 
 import android.annotation.NonNull;
+import android.annotation.Nullable;
 import android.content.Context;
 import android.content.pm.ApplicationInfo;
 import android.content.res.ApkAssets;
-import android.content.res.Resources;
 import android.os.ParcelFileDescriptor;
 import android.os.SharedMemory;
+import android.util.Log;
 
+import com.android.internal.annotations.GuardedBy;
 import com.android.internal.util.ArrayUtils;
 
 import java.io.Closeable;
 import java.io.IOException;
 
 /**
- * Provides methods to load resources from an .apk or .arsc file to pass to
- * {@link Resources#addLoader(ResourceLoader, ResourcesProvider, int)}.
- *
- * It is the responsibility of the app to close any instances.
+ * Provides methods to load resources data from APKs ({@code .apk}) and resources tables
+ * {@code .arsc} for use with {@link ResourcesLoader ResourcesLoader(s)}.
  */
-public final class ResourcesProvider implements AutoCloseable, Closeable {
+public class ResourcesProvider implements AutoCloseable, Closeable {
+    private static final String TAG = "ResourcesProvider";
+    private final Object mLock = new Object();
+
+    @GuardedBy("mLock")
+    private boolean mOpen = true;
+
+    @GuardedBy("mLock")
+    private int mOpenCount = 0;
+
+    @GuardedBy("mLock")
+    private final ApkAssets mApkAssets;
+
+    private final AssetsProvider mAssetsProvider;
 
     /**
-     * Contains no data, assuming that any resource loading behavior will be handled in the
-     * corresponding {@link ResourceLoader}.
+     * Creates an empty ResourcesProvider with no resource data. This is useful for loading assets
+     * that are not associated with resource identifiers.
+     *
+     * @param assetsProvider the assets provider that overrides the loading of file-based resources
      */
     @NonNull
-    public static ResourcesProvider empty() {
-        return new ResourcesProvider(ApkAssets.loadEmptyForLoader());
+    public static ResourcesProvider empty(@NonNull AssetsProvider assetsProvider) {
+        return new ResourcesProvider(ApkAssets.loadEmptyForLoader(), assetsProvider);
     }
 
     /**
-     * Read from an .apk file descriptor.
+     * Creates a ResourcesProvider from an APK ({@code .apk}) file descriptor.
      *
-     * The file descriptor is duplicated and the one passed in may be closed by the application
-     * at any time.
+     * The file descriptor is duplicated and the original may be closed by the application at any
+     * time without affecting the ResourcesProvider.
+     *
+     * @param fileDescriptor the file descriptor of the APK to load
      */
     @NonNull
     public static ResourcesProvider loadFromApk(@NonNull ParcelFileDescriptor fileDescriptor)
             throws IOException {
-        return new ResourcesProvider(
-                ApkAssets.loadApkForLoader(fileDescriptor.getFileDescriptor()));
+        return loadFromApk(fileDescriptor, null);
     }
 
     /**
-     * Read from an .apk file representation in memory.
+     * Creates a ResourcesProvider from an APK ({@code .apk}) file descriptor.
+     *
+     * The file descriptor is duplicated and the original may be closed by the application at any
+     * time without affecting the ResourcesProvider.
+     *
+     * @param fileDescriptor the file descriptor of the APK to load
+     * @param assetsProvider the assets provider that overrides the loading of file-based resources
+     */
+    @NonNull
+    public static ResourcesProvider loadFromApk(@NonNull ParcelFileDescriptor fileDescriptor,
+            @Nullable AssetsProvider assetsProvider)
+            throws IOException {
+        return new ResourcesProvider(
+                ApkAssets.loadApkForLoader(fileDescriptor.getFileDescriptor()), assetsProvider);
+    }
+
+    /**
+     * Creates a ResourcesProvider from an {@code .apk} file representation in memory.
+     *
+     * @param sharedMemory the shared memory containing the data of the APK to load
      */
     @NonNull
     public static ResourcesProvider loadFromApk(@NonNull SharedMemory sharedMemory)
             throws IOException {
-        return new ResourcesProvider(
-                ApkAssets.loadApkForLoader(sharedMemory.getFileDescriptor()));
+        return loadFromApk(sharedMemory, null);
     }
 
     /**
-     * Read from an .arsc file descriptor.
+     * Creates a ResourcesProvider from an {@code .apk} file representation in memory.
      *
-     * The file descriptor is duplicated and the one passed in may be closed by the application
-     * at any time.
+     * @param sharedMemory the shared memory containing the data of the APK to load
+     * @param assetsProvider the assets provider that implements the loading of file-based resources
      */
     @NonNull
-    public static ResourcesProvider loadFromArsc(@NonNull ParcelFileDescriptor fileDescriptor)
+    public static ResourcesProvider loadFromApk(@NonNull SharedMemory sharedMemory,
+            @Nullable AssetsProvider assetsProvider)
             throws IOException {
         return new ResourcesProvider(
-                ApkAssets.loadArscForLoader(fileDescriptor.getFileDescriptor()));
+                ApkAssets.loadApkForLoader(sharedMemory.getFileDescriptor()), assetsProvider);
     }
 
     /**
-     * Read from an .arsc file representation in memory.
+     * Creates a ResourcesProvider from a resources table ({@code .arsc}) file descriptor.
+     *
+     * The file descriptor is duplicated and the original may be closed by the application at any
+     * time without affecting the ResourcesProvider.
+     *
+     * @param fileDescriptor the file descriptor of the resources table to load
+     * @param assetsProvider the assets provider that implements the loading of file-based resources
      */
     @NonNull
-    public static ResourcesProvider loadFromArsc(@NonNull SharedMemory sharedMemory)
+    public static ResourcesProvider loadFromTable(@NonNull ParcelFileDescriptor fileDescriptor,
+            @Nullable AssetsProvider assetsProvider)
             throws IOException {
         return new ResourcesProvider(
-                ApkAssets.loadArscForLoader(sharedMemory.getFileDescriptor()));
+                ApkAssets.loadArscForLoader(fileDescriptor.getFileDescriptor()), assetsProvider);
+    }
+
+    /**
+     * Creates a ResourcesProvider from a resources table ({@code .arsc}) file representation in
+     * memory.
+     *
+     * @param sharedMemory the shared memory containing the data of the resources table to load
+     * @param assetsProvider the assets provider that overrides the loading of file-based resources
+     */
+    @NonNull
+    public static ResourcesProvider loadFromTable(@NonNull SharedMemory sharedMemory,
+            @Nullable AssetsProvider assetsProvider)
+            throws IOException {
+        return new ResourcesProvider(
+                ApkAssets.loadArscForLoader(sharedMemory.getFileDescriptor()), assetsProvider);
     }
 
     /**
      * Read from a split installed alongside the application, which may not have been
      * loaded initially because the application requested isolated split loading.
+     *
+     * @param context a context of the package that contains the split
+     * @param splitName the name of the split to load
      */
     @NonNull
     public static ResourcesProvider loadFromSplit(@NonNull Context context,
@@ -106,15 +166,18 @@
         }
 
         String splitPath = appInfo.getSplitCodePaths()[splitIndex];
-        return new ResourcesProvider(ApkAssets.loadApkForLoader(splitPath));
+        return new ResourcesProvider(ApkAssets.loadApkForLoader(splitPath), null);
     }
 
-
-    @NonNull
-    private final ApkAssets mApkAssets;
-
-    private ResourcesProvider(@NonNull ApkAssets apkAssets) {
+    private ResourcesProvider(@NonNull ApkAssets apkAssets,
+            @Nullable AssetsProvider assetsProvider) {
         this.mApkAssets = apkAssets;
+        this.mAssetsProvider = assetsProvider;
+    }
+
+    @Nullable
+    public AssetsProvider getAssetsProvider() {
+        return mAssetsProvider;
     }
 
     /** @hide */
@@ -123,8 +186,41 @@
         return mApkAssets;
     }
 
+    final void incrementRefCount() {
+        synchronized (mLock) {
+            if (!mOpen) {
+                throw new IllegalStateException("Operation failed: resources provider is closed");
+            }
+            mOpenCount++;
+        }
+    }
+
+    final void decrementRefCount() {
+        synchronized (mLock) {
+            mOpenCount--;
+        }
+    }
+
+    /**
+     * Frees internal data structures. Closed providers can no longer be added to
+     * {@link ResourcesLoader ResourcesLoader(s)}.
+     *
+     * @throws IllegalStateException if provider is currently used by a ResourcesLoader
+     */
     @Override
     public void close() {
+        synchronized (mLock) {
+            if (!mOpen) {
+                return;
+            }
+
+            if (mOpenCount != 0) {
+                throw new IllegalStateException("Failed to close provider used by " + mOpenCount
+                        + " ResourcesLoader instances");
+            }
+            mOpen = false;
+        }
+
         try {
             mApkAssets.close();
         } catch (Throwable ignored) {
@@ -133,7 +229,16 @@
 
     @Override
     protected void finalize() throws Throwable {
-        close();
-        super.finalize();
+        synchronized (mLock) {
+            if (mOpenCount != 0) {
+                Log.w(TAG, "ResourcesProvider " + this + " finalized with non-zero refs: "
+                        + mOpenCount);
+            }
+
+            if (mOpen) {
+                mOpen = false;
+                mApkAssets.close();
+            }
+        }
     }
 }
diff --git a/services/core/java/com/android/server/wm/DisplayPolicy.java b/services/core/java/com/android/server/wm/DisplayPolicy.java
index f8df883..e975bb6 100644
--- a/services/core/java/com/android/server/wm/DisplayPolicy.java
+++ b/services/core/java/com/android/server/wm/DisplayPolicy.java
@@ -2747,7 +2747,8 @@
                 mDisplayContent.getDisplayId(),
                 null /* overrideConfig */,
                 uiContext.getResources().getCompatibilityInfo(),
-                null /* classLoader */);
+                null /* classLoader */,
+                null /* loaders */);
     }
 
     @VisibleForTesting