commit 99900a0e586dc474df52a2f9dda1379170d7e669
author Daichi Hirono <hirono@google.com> Tue Apr 19 17:56:13 2016 +0900
committer Daichi Hirono <hirono@google.com> Tue Apr 26 16:52:44 2016 +0900
tree 979b0c5adc6f046d046ee1b89fc49333b89c5d8f
parent e2be9f4a670198edbe9b1c42422d6d429b8a21f6

Terminate DocumentsUI opened for the specific root.

If USB is opened in DocumentsUI from storage settings and format it from
context menu, a user expects it goes back to storage settings after
formatting the storage.  However, previous we show Downloads as a result
of redirect from the previous USB storage.

The CL changes the logic for callback so that it finishes the activity
if DocumentsUI is opened for the specific root and the root was removed
while a user stays at the root.

Fixes: 28246076
Change-Id: I5548152fc27fd13bd9b75b3083bcfbdd9f93509e

packages/DocumentsUI/src/com/android/documentsui/BaseActivity.java

diff --git a/packages/DocumentsUI/src/com/android/documentsui/BaseActivity.java b/packages/DocumentsUI/src/com/android/documentsui/BaseActivity.java
index 44d7136..50273af 100644
--- a/packages/DocumentsUI/src/com/android/documentsui/BaseActivity.java
+++ b/packages/DocumentsUI/src/com/android/documentsui/BaseActivity.java
@@ -32,6 +32,7 @@
 import android.content.pm.PackageInfo;
 import android.content.pm.PackageManager;
 import android.content.pm.ProviderInfo;
+import android.database.ContentObserver;
 import android.net.Uri;
 import android.os.AsyncTask;
 import android.os.Bundle;
@@ -46,7 +47,6 @@
 import android.view.KeyEvent;
 import android.view.Menu;
 import android.view.MenuItem;
-import android.view.WindowManager;
 import android.widget.Spinner;
 
 import com.android.documentsui.SearchViewManager.SearchManagerListener;
@@ -78,6 +78,12 @@
     List<EventListener> mEventListeners = new ArrayList<>();
 
     private final String mTag;
+    private final ContentObserver mRootsCacheObserver = new ContentObserver(new Handler()) {
+        @Override
+        public void onChange(boolean selfChange) {
+            new HandleRootsChangedTask(BaseActivity.this).execute(getCurrentRoot());
+        }
+    };
 
     @LayoutRes
     private int mLayoutId;
@@ -118,14 +124,8 @@
 
         mRoots = DocumentsApplication.getRootsCache(this);
 
-        mRoots.setOnCacheUpdateListener(
-                new RootsCache.OnCacheUpdateListener() {
-                    @Override
-                    public void onCacheUpdate() {
-                        new HandleRootsChangedTask(BaseActivity.this)
-                                .execute(getCurrentRoot());
-                    }
-                });
+        getContentResolver().registerContentObserver(
+                RootsCache.sNotificationUri, false, mRootsCacheObserver);
 
         mSearchManager = new SearchViewManager(this, icicle);
 
@@ -190,7 +190,7 @@
 
     @Override
     protected void onDestroy() {
-        mRoots.setOnCacheUpdateListener(null);
+        getContentResolver().unregisterContentObserver(mRootsCacheObserver);
         super.onDestroy();
     }
 
@@ -793,6 +793,7 @@
 
     private static final class HandleRootsChangedTask
             extends PairedTask<BaseActivity, RootInfo, RootInfo> {
+        RootInfo mCurrentRoot;
         DocumentInfo mDefaultRootDocument;
 
         public HandleRootsChangedTask(BaseActivity activity) {
@@ -802,11 +803,10 @@
         @Override
         protected RootInfo run(RootInfo... roots) {
             assert(roots.length == 1);
-
-            final RootInfo currentRoot = roots[0];
+            mCurrentRoot = roots[0];
             final Collection<RootInfo> cachedRoots = mOwner.mRoots.getRootsBlocking();
             for (final RootInfo root : cachedRoots) {
-                if (root.getUri().equals(currentRoot.getUri())) {
+                if (root.getUri().equals(mCurrentRoot.getUri())) {
                     // We don't need to change the current root as the current root was not removed.
                     return null;
                 }
@@ -827,6 +827,14 @@
                 return;
             }
 
+            // If the activity has been launched for the specific root and it is removed, finish the
+            // activity.
+            final Uri uri = mOwner.getIntent().getData();
+            if (uri != null && uri.equals(mCurrentRoot.getUri())) {
+                mOwner.finish();
+                return;
+            }
+
             // Clear entire backstack and start in new root.
             mOwner.mState.onRootChanged(defaultRoot);
             mOwner.mSearchManager.update(defaultRoot);

packages/DocumentsUI/src/com/android/documentsui/RootsCache.java

diff --git a/packages/DocumentsUI/src/com/android/documentsui/RootsCache.java b/packages/DocumentsUI/src/com/android/documentsui/RootsCache.java
index 3a04d9d..1eee0e7 100644
--- a/packages/DocumentsUI/src/com/android/documentsui/RootsCache.java
+++ b/packages/DocumentsUI/src/com/android/documentsui/RootsCache.java
@@ -67,7 +67,6 @@
 
     private final Context mContext;
     private final ContentObserver mObserver;
-    private OnCacheUpdateListener mCacheUpdateListener;
 
     private final RootInfo mRecentsRoot;
 
@@ -115,10 +114,6 @@
         }
     }
 
-    static interface OnCacheUpdateListener {
-        void onCacheUpdate();
-    }
-
     /**
      * Gather roots from all known storage providers.
      */
@@ -276,13 +271,6 @@
             return null;
         }
 
-        @Override
-        protected void onPostExecute(Void result) {
-            if (mCacheUpdateListener != null) {
-                mCacheUpdateListener.onCacheUpdate();
-            }
-        }
-
         private void handleDocumentsProvider(ProviderInfo info) {
             // Ignore stopped packages for now; we might query them
             // later during UI interaction.
@@ -441,10 +429,6 @@
         }
     }
 
-    public void setOnCacheUpdateListener(OnCacheUpdateListener cacheUpdateListener) {
-        mCacheUpdateListener = cacheUpdateListener;
-    }
-
     /**
      * Returns the default root for the specified state.
      */