Merge "Start adding unit tests for the invariant device profile / Refactor" into ub-launcher3-burnaby
diff --git a/res/values/config.xml b/res/values/config.xml
index fbce3a4..73de794 100644
--- a/res/values/config.xml
+++ b/res/values/config.xml
@@ -20,6 +20,7 @@
 
 <!-- DragController -->
     <integer name="config_flingToDeleteMinVelocity">-1500</integer>
+    <item type="id" name="drag_event_parity" />
 
 <!-- AllApps & Launcher transitions -->
     <!-- The alpha of the AppsCustomize bg in spring loaded mode -->
diff --git a/src/com/android/launcher3/BaseRecyclerView.java b/src/com/android/launcher3/BaseRecyclerView.java
index b63ef78..8d418f9 100644
--- a/src/com/android/launcher3/BaseRecyclerView.java
+++ b/src/com/android/launcher3/BaseRecyclerView.java
@@ -16,15 +16,28 @@
 
 package com.android.launcher3;
 
+import android.animation.ObjectAnimator;
 import android.content.Context;
+import android.content.res.Resources;
+import android.graphics.Canvas;
+import android.graphics.Color;
+import android.graphics.Paint;
+import android.graphics.Rect;
+import android.graphics.drawable.Drawable;
 import android.support.v7.widget.RecyclerView;
 import android.util.AttributeSet;
 import android.view.MotionEvent;
+import android.view.View;
+import android.view.ViewConfiguration;
+
 import com.android.launcher3.util.Thunk;
 
 /**
- * A base {@link RecyclerView}, which will NOT intercept a touch sequence unless the scrolling
- * velocity is below a predefined threshold.
+ * A base {@link RecyclerView}, which does the following:
+ * <ul>
+ *   <li> NOT intercept a touch unless the scrolling velocity is below a predefined threshold.
+ *   <li> Enable fast scroller.
+ * </ul>
  */
 public class BaseRecyclerView extends RecyclerView
         implements RecyclerView.OnItemTouchListener {
@@ -35,6 +48,53 @@
     @Thunk int mDy = 0;
     private float mDeltaThreshold;
 
+    //
+    // Keeps track of variables required for the second function of this class: fast scroller.
+    //
+
+    private static final float FAST_SCROLL_OVERLAY_Y_OFFSET_FACTOR = 1.5f;
+
+    /**
+     * The current scroll state of the recycler view.  We use this in updateVerticalScrollbarBounds()
+     * and scrollToPositionAtProgress() to determine the scroll position of the recycler view so
+     * that we can calculate what the scroll bar looks like, and where to jump to from the fast
+     * scroller.
+     */
+    public static class ScrollPositionState {
+        // The index of the first visible row
+        public int rowIndex;
+        // The offset of the first visible row
+        public int rowTopOffset;
+        // The height of a given row (they are currently all the same height)
+        public int rowHeight;
+    }
+    // Should be maintained inside overriden method #updateVerticalScrollbarBounds
+    public ScrollPositionState scrollPosState = new ScrollPositionState();
+    public Rect verticalScrollbarBounds = new Rect();
+
+    private boolean mDraggingFastScroller;
+
+    private Drawable mScrollbar;
+    private Drawable mFastScrollerBg;
+    private Rect mTmpFastScrollerInvalidateRect = new Rect();
+    private Rect mFastScrollerBounds = new Rect();
+
+    private String mFastScrollSectionName;
+    private Paint mFastScrollTextPaint;
+    private Rect mFastScrollTextBounds = new Rect();
+    private float mFastScrollAlpha;
+
+    private int mDownX;
+    private int mDownY;
+    private int mLastX;
+    private int mLastY;
+    private int mScrollbarWidth;
+    private int mScrollbarMinHeight;
+    private int mScrollbarInset;
+    private Rect mBackgroundPadding = new Rect();
+
+
+
     public BaseRecyclerView(Context context) {
         this(context, null);
     }
@@ -49,6 +109,24 @@
 
         ScrollListener listener = new ScrollListener();
         setOnScrollListener(listener);
+
+        Resources res = context.getResources();
+        int fastScrollerSize = res.getDimensionPixelSize(R.dimen.all_apps_fast_scroll_popup_size);
+        mScrollbar = res.getDrawable(R.drawable.all_apps_scrollbar_thumb);
+        mFastScrollerBg = res.getDrawable(R.drawable.all_apps_fastscroll_bg);
+        mFastScrollerBg.setBounds(0, 0, fastScrollerSize, fastScrollerSize);
+        mFastScrollTextPaint = new Paint();
+        mFastScrollTextPaint.setColor(Color.WHITE);
+        mFastScrollTextPaint.setAntiAlias(true);
+        mFastScrollTextPaint.setTextSize(res.getDimensionPixelSize(
+                R.dimen.all_apps_fast_scroll_text_size));
+        mScrollbarWidth = res.getDimensionPixelSize(R.dimen.all_apps_fast_scroll_bar_width);
+        mScrollbarMinHeight =
+                res.getDimensionPixelSize(R.dimen.all_apps_fast_scroll_bar_min_height);
+        mScrollbarInset =
+                res.getDimensionPixelSize(R.dimen.all_apps_fast_scroll_scrubber_touch_inset);
+        setFastScrollerAlpha(mFastScrollAlpha);
+        setOverScrollMode(View.OVER_SCROLL_NEVER);
     }
 
     private class ScrollListener extends OnScrollListener {
@@ -68,17 +146,74 @@
         addOnItemTouchListener(this);
     }
 
+    /**
+     * We intercept the touch handling only to support fast scrolling when initiated from the
+     * scroll bar.  Otherwise, we fall back to the default RecyclerView touch handling.
+     */
     @Override
     public boolean onInterceptTouchEvent(RecyclerView rv, MotionEvent ev) {
-        if (shouldStopScroll(ev)) {
-            stopScroll();
-        }
-        return false;
+        return handleTouchEvent(ev);
     }
 
     @Override
     public void onTouchEvent(RecyclerView rv, MotionEvent ev) {
-        // Do nothing.
+        handleTouchEvent(ev);
+    }
+
+    /**
+     * Handles the touch event and determines whether to show the fast scroller (or updates it if
+     * it is already showing).
+     */
+    private boolean handleTouchEvent(MotionEvent ev) {
+        ViewConfiguration config = ViewConfiguration.get(getContext());
+
+        int action = ev.getAction();
+        int x = (int) ev.getX();
+        int y = (int) ev.getY();
+        switch (action) {
+            case MotionEvent.ACTION_DOWN:
+                // Keep track of the down positions
+                mDownX = mLastX = x;
+                mDownY = mLastY = y;
+                if (shouldStopScroll(ev)) {
+                    stopScroll();
+                }
+                break;
+            case MotionEvent.ACTION_MOVE:
+                // Check if we are scrolling
+                if (!mDraggingFastScroller && isPointNearScrollbar(mDownX, mDownY) &&
+                        Math.abs(y - mDownY) > config.getScaledTouchSlop()) {
+                    getParent().requestDisallowInterceptTouchEvent(true);
+                    mDraggingFastScroller = true;
+                    animateFastScrollerVisibility(true);
+                }
+                if (mDraggingFastScroller) {
+                    mLastX = x;
+                    mLastY = y;
+
+                    // Scroll to the right position, and update the section name
+                    int top = getPaddingTop() + (mFastScrollerBg.getBounds().height() / 2);
+                    int bottom = getHeight() - getPaddingBottom() -
+                            (mFastScrollerBg.getBounds().height() / 2);
+                    float boundedY = (float) Math.max(top, Math.min(bottom, y));
+                    mFastScrollSectionName = scrollToPositionAtProgress((boundedY - top) /
+                            (bottom - top));
+
+                    // Combine the old and new fast scroller bounds to create the full invalidate
+                    // rect
+                    mTmpFastScrollerInvalidateRect.set(mFastScrollerBounds);
+                    updateFastScrollerBounds();
+                    mTmpFastScrollerInvalidateRect.union(mFastScrollerBounds);
+                    invalidateFastScroller(mTmpFastScrollerInvalidateRect);
+                }
+                break;
+            case MotionEvent.ACTION_UP:
+            case MotionEvent.ACTION_CANCEL:
+                mDraggingFastScroller = false;
+                animateFastScrollerVisibility(false);
+                break;
+        }
+        return mDraggingFastScroller;
     }
 
     public void onRequestDisallowInterceptTouchEvent(boolean disallowIntercept) {
@@ -99,4 +234,127 @@
         }
         return false;
     }
+
+    @Override
+    protected void dispatchDraw(Canvas canvas) {
+        super.dispatchDraw(canvas);
+        drawVerticalScrubber(canvas);
+        drawFastScrollerPopup(canvas);
+    }
+
+    /**
+     * Draws the vertical scrollbar.
+     */
+    private void drawVerticalScrubber(Canvas canvas) {
+        updateVerticalScrollbarBounds();
+
+        // Draw the scroll bar
+        int restoreCount = canvas.save(Canvas.MATRIX_SAVE_FLAG);
+        canvas.translate(verticalScrollbarBounds.left, verticalScrollbarBounds.top);
+        mScrollbar.setBounds(0, 0, mScrollbarWidth, verticalScrollbarBounds.height());
+        mScrollbar.draw(canvas);
+        canvas.restoreToCount(restoreCount);
+    }
+
+    /**
+     * Draws the fast scroller popup.
+     */
+    private void drawFastScrollerPopup(Canvas canvas) {
+        if (mFastScrollAlpha > 0f && mFastScrollSectionName != null && !mFastScrollSectionName.isEmpty()) {
+            // Draw the fast scroller popup
+            int restoreCount = canvas.save(Canvas.MATRIX_SAVE_FLAG);
+            canvas.translate(mFastScrollerBounds.left, mFastScrollerBounds.top);
+            mFastScrollerBg.setAlpha((int) (mFastScrollAlpha * 255));
+            mFastScrollerBg.draw(canvas);
+            mFastScrollTextPaint.setAlpha((int) (mFastScrollAlpha * 255));
+            mFastScrollTextPaint.getTextBounds(mFastScrollSectionName, 0,
+                    mFastScrollSectionName.length(), mFastScrollTextBounds);
+            float textWidth = mFastScrollTextPaint.measureText(mFastScrollSectionName);
+            canvas.drawText(mFastScrollSectionName,
+                    (mFastScrollerBounds.width() - textWidth) / 2,
+                    mFastScrollerBounds.height() -
+                            (mFastScrollerBounds.height() - mFastScrollTextBounds.height()) / 2,
+                    mFastScrollTextPaint);
+            canvas.restoreToCount(restoreCount);
+        }
+    }
+
+    /**
+     * Returns the scroll bar width.
+     */
+    public int getScrollbarWidth() {
+        return mScrollbarWidth;
+    }
+
+    /**
+     * Sets the fast scroller alpha.
+     */
+    public void setFastScrollerAlpha(float alpha) {
+        mFastScrollAlpha = alpha;
+        invalidateFastScroller(mFastScrollerBounds);
+    }
+
+    /**
+     * Maps the touch (from 0..1) to the adapter position that should be visible.
+     * <p>Override in each subclass of this base class.
+     */
+    public String scrollToPositionAtProgress(float touchFraction) {
+        return null;
+    }
+
+    /**
+     * Updates the bounds for the scrollbar.
+     * <p>Override in each subclass of this base class.
+     */
+    public void updateVerticalScrollbarBounds() {};
+
+    /**
+     * Animates the visibility of the fast scroller popup.
+     */
+    private void animateFastScrollerVisibility(boolean visible) {
+        ObjectAnimator anim = ObjectAnimator.ofFloat(this, "fastScrollerAlpha", visible ? 1f : 0f);
+        anim.setDuration(visible ? 200 : 150);
+        anim.start();
+    }
+
+    /**
+     * Invalidates the fast scroller popup.
+     */
+    protected void invalidateFastScroller(Rect bounds) {
+        invalidate(bounds.left, bounds.top, bounds.right, bounds.bottom);
+    }
+
+    /**
+     * Returns whether a given point is near the scrollbar.
+     */
+    private boolean isPointNearScrollbar(int x, int y) {
+        // Check if we are scrolling
+        updateVerticalScrollbarBounds();
+        verticalScrollbarBounds.inset(mScrollbarInset, mScrollbarInset);
+        return verticalScrollbarBounds.contains(x, y);
+    }
+
+    /**
+     * Updates the bounds for the fast scroller.
+     */
+    private void updateFastScrollerBounds() {
+        if (mFastScrollAlpha > 0f && !mFastScrollSectionName.isEmpty()) {
+            int x;
+            int y;
+
+            // Calculate the position for the fast scroller popup
+            Rect bgBounds = mFastScrollerBg.getBounds();
+            if (Utilities.isRtl(getResources())) {
+                x = mBackgroundPadding.left + getScrollBarSize();
+            } else {
+                x = getWidth() - getPaddingRight() - getScrollBarSize() - bgBounds.width();
+            }
+            y = mLastY - (int) (FAST_SCROLL_OVERLAY_Y_OFFSET_FACTOR * bgBounds.height());
+            y = Math.max(getPaddingTop(), Math.min(y, getHeight() - getPaddingBottom() -
+                    bgBounds.height()));
+            mFastScrollerBounds.set(x, y, x + bgBounds.width(), y + bgBounds.height());
+        } else {
+            mFastScrollerBounds.setEmpty();
+        }
+    }
 }
\ No newline at end of file
diff --git a/src/com/android/launcher3/CellLayout.java b/src/com/android/launcher3/CellLayout.java
index 2b1cfe0..61567ac 100644
--- a/src/com/android/launcher3/CellLayout.java
+++ b/src/com/android/launcher3/CellLayout.java
@@ -168,7 +168,6 @@
     private int[] mDirectionVector = new int[2];
     int[] mPreviousReorderDirection = new int[2];
     private static final int INVALID_DIRECTION = -100;
-    private DropTarget.DragEnforcer mDragEnforcer;
 
     private final Rect mTempRect = new Rect();
 
@@ -188,7 +187,6 @@
 
     public CellLayout(Context context, AttributeSet attrs, int defStyle) {
         super(context, attrs, defStyle);
-        mDragEnforcer = new DropTarget.DragEnforcer(context);
 
         // A ViewGroup usually does not draw, but CellLayout needs to draw a rectangle to show
         // the user where a dragged item will land when dropped.
@@ -2637,7 +2635,6 @@
      * or it may have begun on another layout.
      */
     void onDragEnter() {
-        mDragEnforcer.onDragEnter();
         mDragging = true;
     }
 
@@ -2645,7 +2642,6 @@
      * Called when drag has left this CellLayout or has been completed (successfully or not)
      */
     void onDragExit() {
-        mDragEnforcer.onDragExit();
         // This can actually be called when we aren't in a drag, e.g. when adding a new
         // item to this layout via the customize drawer.
         // Guard against that case.
diff --git a/src/com/android/launcher3/DragLayer.java b/src/com/android/launcher3/DragLayer.java
index 423a9a3..41e053e 100644
--- a/src/com/android/launcher3/DragLayer.java
+++ b/src/com/android/launcher3/DragLayer.java
@@ -918,7 +918,7 @@
     void showPageHints() {
         mShowPageHints = true;
         Workspace workspace = mLauncher.getWorkspace();
-        getDescendantRectRelativeToSelf(workspace.getChildAt(workspace.getChildCount() - 1),
+        getDescendantRectRelativeToSelf(workspace.getChildAt(workspace.numCustomPages()),
                 mScrollChildPosition);
         invalidate();
     }
diff --git a/src/com/android/launcher3/DropTarget.java b/src/com/android/launcher3/DropTarget.java
index a3828c1..c8fac54 100644
--- a/src/com/android/launcher3/DropTarget.java
+++ b/src/com/android/launcher3/DropTarget.java
@@ -16,10 +16,8 @@
 
 package com.android.launcher3;
 
-import android.content.Context;
 import android.graphics.PointF;
 import android.graphics.Rect;
-import android.util.Log;
 
 /**
  * Interface defining an object that can receive a drag.
@@ -93,43 +91,6 @@
         }
     }
 
-    public static class DragEnforcer implements DragController.DragListener {
-        int dragParity = 0;
-
-        public DragEnforcer(Context context) {
-            Launcher launcher = (Launcher) context;
-            launcher.getDragController().addDragListener(this);
-        }
-
-        void onDragEnter() {
-            dragParity++;
-            if (dragParity != 1) {
-                Log.e(TAG, "onDragEnter: Drag contract violated: " + dragParity);
-            }
-        }
-
-        void onDragExit() {
-            dragParity--;
-            if (dragParity != 0) {
-                Log.e(TAG, "onDragExit: Drag contract violated: " + dragParity);
-            }
-        }
-
-        @Override
-        public void onDragStart(DragSource source, Object info, int dragAction) {
-            if (dragParity != 0) {
-                Log.e(TAG, "onDragEnter: Drag contract violated: " + dragParity);
-            }
-        }
-
-        @Override
-        public void onDragEnd() {
-            if (dragParity != 0) {
-                Log.e(TAG, "onDragExit: Drag contract violated: " + dragParity);
-            }
-        }
-    }
-
     /**
      * Used to temporarily disable certain drop targets
      *
diff --git a/src/com/android/launcher3/IconCache.java b/src/com/android/launcher3/IconCache.java
index 0c91a71..6dfca9e 100644
--- a/src/com/android/launcher3/IconCache.java
+++ b/src/com/android/launcher3/IconCache.java
@@ -49,10 +49,8 @@
 
 import java.util.HashMap;
 import java.util.HashSet;
-import java.util.Iterator;
 import java.util.List;
 import java.util.Locale;
-import java.util.Map.Entry;
 import java.util.Stack;
 
 /**
@@ -75,8 +73,8 @@
 
     @Thunk static class CacheEntry {
         public Bitmap icon;
-        public CharSequence title;
-        public CharSequence contentDescription;
+        public CharSequence title = "";
+        public CharSequence contentDescription = "";
         public boolean isLowResIcon;
     }
 
@@ -367,13 +365,6 @@
     }
 
     /**
-     * Empty out the cache.
-     */
-    public synchronized void flush() {
-        mCache.clear();
-    }
-
-    /**
      * Fetches high-res icon for the provided ItemInfo and updates the caller when done.
      * @return a request ID that can be used to cancel the request.
      */
@@ -584,7 +575,7 @@
         CacheEntry entry = mCache.get(cacheKey);
         if (entry == null || (entry.isLowResIcon && !useLowResIcon)) {
             entry = new CacheEntry();
-            mCache.put(cacheKey, entry);
+            boolean entryUpdated = true;
 
             // Check the DB first.
             if (!getEntryFromDB(cn, user, entry, useLowResIcon)) {
@@ -609,8 +600,14 @@
 
                 } catch (NameNotFoundException e) {
                     if (DEBUG) Log.d(TAG, "Application not installed " + packageName);
+                    entryUpdated = false;
                 }
             }
+
+            // Only add a filled-out entry to the cache
+            if (entryUpdated) {
+                mCache.put(cacheKey, entry);
+            }
         }
         return entry;
     }
diff --git a/src/com/android/launcher3/Launcher.java b/src/com/android/launcher3/Launcher.java
index 5dd64e0..5dac3b3 100644
--- a/src/com/android/launcher3/Launcher.java
+++ b/src/com/android/launcher3/Launcher.java
@@ -88,6 +88,7 @@
 import android.view.Window;
 import android.view.WindowManager;
 import android.view.accessibility.AccessibilityEvent;
+import android.view.animation.OvershootInterpolator;
 import android.view.inputmethod.InputMethodManager;
 import android.widget.Advanceable;
 import android.widget.FrameLayout;
@@ -111,11 +112,8 @@
 import com.android.launcher3.widget.WidgetHostViewLoader;
 import com.android.launcher3.widget.WidgetsContainerView;
 
-import java.io.DataInputStream;
-import java.io.DataOutputStream;
 import java.io.File;
 import java.io.FileDescriptor;
-import java.io.FileNotFoundException;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.PrintWriter;
@@ -163,14 +161,14 @@
     private static final int WORKSPACE_BACKGROUND_TRANSPARENT = 1;
     private static final int WORKSPACE_BACKGROUND_BLACK = 2;
 
+    private static final float BOUNCE_ANIMATION_TENSION = 1.3f;
+
     /**
      * IntentStarter uses request codes starting with this. This must be greater than all activity
      * request codes used internally.
      */
     protected static final int REQUEST_LAST = 100;
 
-    static final String EXTRA_SHORTCUT_DUPLICATE = "duplicate";
-
     static final int SCREEN_COUNT = 5;
 
     // To turn on these properties, type
@@ -309,8 +307,6 @@
     private boolean mHasFocus = false;
     private boolean mAttached = false;
 
-    @Thunk static LocaleConfiguration sLocaleConfiguration = null;
-
     private static LongArrayMap<FolderInfo> sFolders = new LongArrayMap<>();
 
     private View.OnTouchListener mHapticFeedbackTouchListener;
@@ -468,7 +464,6 @@
                     Environment.getExternalStorageDirectory() + "/launcher");
         }
 
-        checkForLocaleChange();
         setContentView(R.layout.launcher);
 
         setupViews();
@@ -558,6 +553,35 @@
                 }
             }
         });
+        mLauncherCallbacks.setLauncherSearchCallback(new Launcher.LauncherSearchCallbacks() {
+            private boolean mImportanceStored = false;
+            private int mWorkspaceImportanceForAccessibility =
+                View.IMPORTANT_FOR_ACCESSIBILITY_AUTO;
+            private int mHotseatImportanceForAccessibility = View.IMPORTANT_FOR_ACCESSIBILITY_AUTO;
+
+            @Override
+            public void onSearchOverlayOpened() {
+                if (mImportanceStored) {
+                    return;
+                }
+                // The underlying workspace and hotseat are temporarily suppressed by the search
+                // overlay. So they sholudn't be accessible.
+                mWorkspaceImportanceForAccessibility = mWorkspace.getImportantForAccessibility();
+                mHotseatImportanceForAccessibility = mHotseat.getImportantForAccessibility();
+                mWorkspace.setImportantForAccessibility(
+                    View.IMPORTANT_FOR_ACCESSIBILITY_NO_HIDE_DESCENDANTS);
+                mHotseat.setImportantForAccessibility(
+                    View.IMPORTANT_FOR_ACCESSIBILITY_NO_HIDE_DESCENDANTS);
+                mImportanceStored = true;
+            }
+
+            @Override
+            public void onSearchOverlayClosed() {
+                mWorkspace.setImportantForAccessibility(mWorkspaceImportanceForAccessibility);
+                mHotseat.setImportantForAccessibility(mHotseatImportanceForAccessibility);
+                mImportanceStored = false;
+            }
+        });
         return true;
     }
 
@@ -606,108 +630,6 @@
         }
     }
 
-    @Thunk void checkForLocaleChange() {
-        if (sLocaleConfiguration == null) {
-            new AsyncTask<Void, Void, LocaleConfiguration>() {
-                @Override
-                protected LocaleConfiguration doInBackground(Void... unused) {
-                    LocaleConfiguration localeConfiguration = new LocaleConfiguration();
-                    readConfiguration(Launcher.this, localeConfiguration);
-                    return localeConfiguration;
-                }
-
-                @Override
-                protected void onPostExecute(LocaleConfiguration result) {
-                    sLocaleConfiguration = result;
-                    checkForLocaleChange();  // recursive, but now with a locale configuration
-                }
-            }.execute();
-            return;
-        }
-
-        final Configuration configuration = getResources().getConfiguration();
-
-        final String previousLocale = sLocaleConfiguration.locale;
-        final String locale = configuration.locale.toString();
-
-        final int previousMcc = sLocaleConfiguration.mcc;
-        final int mcc = configuration.mcc;
-
-        final int previousMnc = sLocaleConfiguration.mnc;
-        final int mnc = configuration.mnc;
-
-        boolean localeChanged = !locale.equals(previousLocale) || mcc != previousMcc || mnc != previousMnc;
-
-        if (localeChanged) {
-            sLocaleConfiguration.locale = locale;
-            sLocaleConfiguration.mcc = mcc;
-            sLocaleConfiguration.mnc = mnc;
-
-            mIconCache.flush();
-
-            final LocaleConfiguration localeConfiguration = sLocaleConfiguration;
-            new AsyncTask<Void, Void, Void>() {
-                public Void doInBackground(Void ... args) {
-                    writeConfiguration(Launcher.this, localeConfiguration);
-                    return null;
-                }
-            }.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR, (Void) null);
-        }
-    }
-
-    @Thunk static class LocaleConfiguration {
-        public String locale;
-        public int mcc = -1;
-        public int mnc = -1;
-    }
-
-    @Thunk static void readConfiguration(Context context, LocaleConfiguration configuration) {
-        DataInputStream in = null;
-        try {
-            in = new DataInputStream(context.openFileInput(LauncherFiles.LAUNCHER_PREFERENCES));
-            configuration.locale = in.readUTF();
-            configuration.mcc = in.readInt();
-            configuration.mnc = in.readInt();
-        } catch (FileNotFoundException e) {
-            // Ignore
-        } catch (IOException e) {
-            // Ignore
-        } finally {
-            if (in != null) {
-                try {
-                    in.close();
-                } catch (IOException e) {
-                    // Ignore
-                }
-            }
-        }
-    }
-
-    @Thunk static void writeConfiguration(Context context, LocaleConfiguration configuration) {
-        DataOutputStream out = null;
-        try {
-            out = new DataOutputStream(context.openFileOutput(
-                    LauncherFiles.LAUNCHER_PREFERENCES, MODE_PRIVATE));
-            out.writeUTF(configuration.locale);
-            out.writeInt(configuration.mcc);
-            out.writeInt(configuration.mnc);
-            out.flush();
-        } catch (FileNotFoundException e) {
-            // Ignore
-        } catch (IOException e) {
-            //noinspection ResultOfMethodCallIgnored
-            context.getFileStreamPath(LauncherFiles.LAUNCHER_PREFERENCES).delete();
-        } finally {
-            if (out != null) {
-                try {
-                    out.close();
-                } catch (IOException e) {
-                    // Ignore
-                }
-            }
-        }
-    }
-
     public Stats getStats() {
         return mStats;
     }
@@ -1055,8 +977,8 @@
         }
 
         // Background was set to gradient in onPause(), restore to transparent if in all apps.
-        setWorkspaceBackground(mState == State.WORKSPACE ? WORKSPACE_BACKGROUND_TRANSPARENT
-                : WORKSPACE_BACKGROUND_GRADIENT);
+        setWorkspaceBackground(mState == State.WORKSPACE ? WORKSPACE_BACKGROUND_GRADIENT
+                : WORKSPACE_BACKGROUND_TRANSPARENT);
 
         mPaused = false;
         if (mRestoring || mOnResumeNeedsLoad) {
@@ -1207,6 +1129,18 @@
         public void dismissAllApps();
     }
 
+    public interface LauncherSearchCallbacks {
+        /**
+         * Called when the search overlay is shown.
+         */
+        public void onSearchOverlayOpened();
+
+        /**
+         * Called when the search overlay is dismissed.
+         */
+        public void onSearchOverlayClosed();
+    }
+
     public interface LauncherOverlayCallbacks {
         /**
          * This method indicates whether a call to {@link #enterFullImmersion()} will succeed,
@@ -4194,7 +4128,7 @@
                 PropertyValuesHolder.ofFloat("scaleY", 1f));
         bounceAnim.setDuration(InstallShortcutReceiver.NEW_SHORTCUT_BOUNCE_DURATION);
         bounceAnim.setStartDelay(i * InstallShortcutReceiver.NEW_SHORTCUT_STAGGER_DELAY);
-        bounceAnim.setInterpolator(new SmoothPagedView.OvershootInterpolator());
+        bounceAnim.setInterpolator(new OvershootInterpolator(BOUNCE_ANIMATION_TENSION));
         return bounceAnim;
     }
 
diff --git a/src/com/android/launcher3/LauncherAnimUtils.java b/src/com/android/launcher3/LauncherAnimUtils.java
index 6ff7666..6a248a3 100644
--- a/src/com/android/launcher3/LauncherAnimUtils.java
+++ b/src/com/android/launcher3/LauncherAnimUtils.java
@@ -26,6 +26,9 @@
 import android.view.View;
 import android.view.ViewAnimationUtils;
 import android.view.ViewTreeObserver;
+
+import com.android.launcher3.util.UiThreadCircularReveal;
+
 import java.util.HashSet;
 import java.util.WeakHashMap;
 
@@ -130,13 +133,11 @@
     }
 
     @TargetApi(Build.VERSION_CODES.LOLLIPOP)
-    public static Animator createCircularReveal(View view, int centerX,
+    public static ValueAnimator createCircularReveal(View view, int centerX,
             int centerY, float startRadius, float endRadius) {
-        Animator anim = ViewAnimationUtils.createCircularReveal(view, centerX,
+        ValueAnimator anim = UiThreadCircularReveal.createCircularReveal(view, centerX,
                 centerY, startRadius, endRadius);
-        if (anim instanceof ValueAnimator) {
-            new FirstFrameAnimatorHelper((ValueAnimator) anim, view);
-        }
+        new FirstFrameAnimatorHelper(anim, view);
         return anim;
     }
 }
diff --git a/src/com/android/launcher3/LauncherCallbacks.java b/src/com/android/launcher3/LauncherCallbacks.java
index 0124d1f..a5f36ba 100644
--- a/src/com/android/launcher3/LauncherCallbacks.java
+++ b/src/com/android/launcher3/LauncherCallbacks.java
@@ -119,4 +119,11 @@
      */
     public void setLauncherAppsCallback(Object callbacks);
 
+    /**
+     * Sets the callbacks to allow reacting the actions of search overlays of the launcher.
+     *
+     * @param callbacks A set of callbacks to the Launcher, is actually a LauncherSearchCallback,
+     *                  but for implementation purposes is passed around as an object.
+     */
+    public void setLauncherSearchCallback(Object callbacks);
 }
diff --git a/src/com/android/launcher3/LauncherExtension.java b/src/com/android/launcher3/LauncherExtension.java
index 14ad601..09a105b 100644
--- a/src/com/android/launcher3/LauncherExtension.java
+++ b/src/com/android/launcher3/LauncherExtension.java
@@ -289,6 +289,11 @@
             // Do nothing
         }
 
+        @Override
+        public void setLauncherSearchCallback(Object callbacks) {
+            // Do nothing
+        }
+
         class LauncherExtensionOverlay implements LauncherOverlay {
             LauncherOverlayCallbacks mLauncherOverlayCallbacks;
             ViewGroup mOverlayView;
diff --git a/src/com/android/launcher3/LauncherFiles.java b/src/com/android/launcher3/LauncherFiles.java
index 03ec4bf..c08cd0b 100644
--- a/src/com/android/launcher3/LauncherFiles.java
+++ b/src/com/android/launcher3/LauncherFiles.java
@@ -17,7 +17,6 @@
     public static final String DEFAULT_WALLPAPER_THUMBNAIL = "default_thumb2.jpg";
     public static final String DEFAULT_WALLPAPER_THUMBNAIL_OLD = "default_thumb.jpg";
     public static final String LAUNCHER_DB = "launcher.db";
-    public static final String LAUNCHER_PREFERENCES = "launcher.preferences";
     public static final String SHARED_PREFERENCES_KEY = "com.android.launcher3.prefs";
     public static final String WALLPAPER_CROP_PREFERENCES_KEY =
             "com.android.launcher3.WallpaperCropActivity";
@@ -31,7 +30,6 @@
             DEFAULT_WALLPAPER_THUMBNAIL,
             DEFAULT_WALLPAPER_THUMBNAIL_OLD,
             LAUNCHER_DB,
-            LAUNCHER_PREFERENCES,
             SHARED_PREFERENCES_KEY + XML,
             WALLPAPER_CROP_PREFERENCES_KEY + XML,
             WALLPAPER_IMAGES_DB,
@@ -43,5 +41,6 @@
     public static final List<String> OBSOLETE_FILES = Collections.unmodifiableList(Arrays.asList(
             "launches.log",
             "stats.log",
+            "launcher.preferences",
             "com.android.launcher3.compat.PackageInstallerCompatV16.queue"));
 }
diff --git a/src/com/android/launcher3/LauncherStateTransitionAnimation.java b/src/com/android/launcher3/LauncherStateTransitionAnimation.java
index f373fde..a006d14 100644
--- a/src/com/android/launcher3/LauncherStateTransitionAnimation.java
+++ b/src/com/android/launcher3/LauncherStateTransitionAnimation.java
@@ -26,12 +26,14 @@
 import android.content.res.Resources;
 import android.util.Log;
 import android.view.View;
-import android.view.ViewAnimationUtils;
 import android.view.animation.AccelerateInterpolator;
 import android.view.animation.DecelerateInterpolator;
+
 import com.android.launcher3.allapps.AllAppsContainerView;
+import com.android.launcher3.util.UiThreadCircularReveal;
 import com.android.launcher3.util.Thunk;
 import com.android.launcher3.widget.WidgetsContainerView;
+
 import java.util.HashMap;
 
 /**
@@ -320,7 +322,7 @@
                 float startRadius = pCb.getMaterialRevealViewStartFinalRadius();
                 AnimatorListenerAdapter listener = pCb.getMaterialRevealViewAnimatorListener(
                         revealView, allAppsButtonView);
-                Animator reveal = ViewAnimationUtils.createCircularReveal(revealView, width / 2,
+                Animator reveal = UiThreadCircularReveal.createCircularReveal(revealView, width / 2,
                         height / 2, startRadius, revealRadius);
                 reveal.setDuration(revealDuration);
                 reveal.setInterpolator(new LogDecelerateInterpolator(100, 0));
@@ -587,14 +589,14 @@
                 TimeInterpolator decelerateInterpolator = material ?
                         new LogDecelerateInterpolator(100, 0) :
                         new DecelerateInterpolator(1f);
-                ObjectAnimator panelDriftY = LauncherAnimUtils.ofFloat(revealView, "translationY",
+                ObjectAnimator panelDriftY = ObjectAnimator.ofFloat(revealView, "translationY",
                         0, revealViewToYDrift);
                 panelDriftY.setDuration(revealDuration - SINGLE_FRAME_DELAY);
                 panelDriftY.setStartDelay(itemsAlphaStagger + SINGLE_FRAME_DELAY);
                 panelDriftY.setInterpolator(decelerateInterpolator);
                 mStateAnimation.play(panelDriftY);
 
-                ObjectAnimator panelDriftX = LauncherAnimUtils.ofFloat(revealView, "translationX",
+                ObjectAnimator panelDriftX = ObjectAnimator.ofFloat(revealView, "translationX",
                         0, revealViewToXDrift);
                 panelDriftX.setDuration(revealDuration - SINGLE_FRAME_DELAY);
                 panelDriftX.setStartDelay(itemsAlphaStagger + SINGLE_FRAME_DELAY);
@@ -605,7 +607,7 @@
                 final float revealViewToAlpha = !material ? 0f :
                         pCb.getMaterialRevealViewFinalAlpha(revealView);
                 if (revealViewToAlpha != 1f) {
-                    ObjectAnimator panelAlpha = LauncherAnimUtils.ofFloat(revealView, "alpha",
+                    ObjectAnimator panelAlpha = ObjectAnimator.ofFloat(revealView, "alpha",
                             1f, revealViewToAlpha);
                     panelAlpha.setDuration(material ? revealDuration : 150);
                     panelAlpha.setStartDelay(material ? 0 : itemsAlphaStagger + SINGLE_FRAME_DELAY);
@@ -617,7 +619,7 @@
                 layerViews.put(contentView, BUILD_AND_SET_LAYER);
 
                 // Create the individual animators
-                ObjectAnimator pageDrift = LauncherAnimUtils.ofFloat(contentView, "translationY",
+                ObjectAnimator pageDrift = ObjectAnimator.ofFloat(contentView, "translationY",
                         0, revealViewToYDrift);
                 contentView.setTranslationY(0);
                 pageDrift.setDuration(revealDuration - SINGLE_FRAME_DELAY);
@@ -626,7 +628,7 @@
                 mStateAnimation.play(pageDrift);
 
                 contentView.setAlpha(1f);
-                ObjectAnimator itemsAlpha = LauncherAnimUtils.ofFloat(contentView, "alpha", 1f, 0f);
+                ObjectAnimator itemsAlpha = ObjectAnimator.ofFloat(contentView, "alpha", 1f, 0f);
                 itemsAlpha.setDuration(100);
                 itemsAlpha.setInterpolator(decelerateInterpolator);
                 mStateAnimation.play(itemsAlpha);
@@ -636,9 +638,8 @@
                     float finalRadius = pCb.getMaterialRevealViewStartFinalRadius();
                     AnimatorListenerAdapter listener =
                             pCb.getMaterialRevealViewAnimatorListener(revealView, allAppsButtonView);
-                    Animator reveal =
-                            LauncherAnimUtils.createCircularReveal(revealView, width / 2,
-                                    height / 2, revealRadius, finalRadius);
+                    Animator reveal = UiThreadCircularReveal.createCircularReveal(revealView, width / 2,
+                            height / 2, revealRadius, finalRadius);
                     reveal.setInterpolator(new LogDecelerateInterpolator(100, 0));
                     reveal.setDuration(revealDuration);
                     reveal.setStartDelay(itemsAlphaStagger);
@@ -782,4 +783,4 @@
             mStateAnimation = null;
         }
     }
-}
\ No newline at end of file
+}
diff --git a/src/com/android/launcher3/PagedView.java b/src/com/android/launcher3/PagedView.java
index dda9a16..9271e8b 100644
--- a/src/com/android/launcher3/PagedView.java
+++ b/src/com/android/launcher3/PagedView.java
@@ -146,7 +146,6 @@
     protected OnLongClickListener mLongClickListener;
 
     protected int mTouchSlop;
-    private int mPagingTouchSlop;
     private int mMaximumVelocity;
     protected int mPageLayoutWidthGap;
     protected int mPageLayoutHeightGap;
@@ -172,14 +171,6 @@
     // If true, modify alpha of neighboring pages as user scrolls left/right
     protected boolean mFadeInAdjacentScreens = false;
 
-    // It true, use a different slop parameter (pagingTouchSlop = 2 * touchSlop) for deciding
-    // to switch to a new page
-    protected boolean mUsePagingTouchSlop = true;
-
-    // If true, the subclass should directly update scrollX itself in its computeScroll method
-    // (SmoothPagedView does this)
-    protected boolean mDeferScrollUpdate = false;
-
     protected boolean mIsPageMoving = false;
 
     private boolean mWasInOverscroll = false;
@@ -264,7 +255,6 @@
 
         final ViewConfiguration configuration = ViewConfiguration.get(getContext());
         mTouchSlop = configuration.getScaledPagingTouchSlop();
-        mPagingTouchSlop = configuration.getScaledPagingTouchSlop();
         mMaximumVelocity = configuration.getScaledMaximumFlingVelocity();
         mDensity = getResources().getDisplayMetrics().density;
 
@@ -633,6 +623,11 @@
             if (mCurrentPage != getNextPage()) {
                 AccessibilityEvent ev =
                         AccessibilityEvent.obtain(AccessibilityEvent.TYPE_VIEW_SCROLLED);
+                ev.setScrollable(true);
+                ev.setScrollX(getScrollX());
+                ev.setScrollY(getScrollY());
+                ev.setMaxScrollX(mMaxScrollX);
+                ev.setMaxScrollY(0);
 
                 sendAccessibilityEventUnchecked(ev);
             }
@@ -853,7 +848,7 @@
         int offsetY = getViewportOffsetY();
 
         // Update the viewport offsets
-        mViewport.offset(offsetX,  offsetY);
+        mViewport.offset(offsetX, offsetY);
 
         final int startIndex = mIsRtl ? childCount - 1 : 0;
         final int endIndex = mIsRtl ? -1 : childCount;
@@ -1434,25 +1429,20 @@
         if (!isTouchPointInViewportWithBuffer((int) x, (int) y)) return;
 
         final int xDiff = (int) Math.abs(x - mLastMotionX);
-        final int yDiff = (int) Math.abs(y - mLastMotionY);
 
         final int touchSlop = Math.round(touchSlopScale * mTouchSlop);
-        boolean xPaged = xDiff > mPagingTouchSlop;
         boolean xMoved = xDiff > touchSlop;
-        boolean yMoved = yDiff > touchSlop;
 
-        if (xMoved || xPaged || yMoved) {
-            if (mUsePagingTouchSlop ? xPaged : xMoved) {
-                // Scroll if the user moved far enough along the X axis
-                mTouchState = TOUCH_STATE_SCROLLING;
-                mTotalMotionX += Math.abs(mLastMotionX - x);
-                mLastMotionX = x;
-                mLastMotionXRemainder = 0;
-                mTouchX = getViewportOffsetX() + getScrollX();
-                mSmoothingTime = System.nanoTime() / NANOTIME_DIV;
-                onScrollInteractionBegin();
-                pageBeginMoving();
-            }
+        if (xMoved) {
+            // Scroll if the user moved far enough along the X axis
+            mTouchState = TOUCH_STATE_SCROLLING;
+            mTotalMotionX += Math.abs(mLastMotionX - x);
+            mLastMotionX = x;
+            mLastMotionXRemainder = 0;
+            mTouchX = getViewportOffsetX() + getScrollX();
+            mSmoothingTime = System.nanoTime() / NANOTIME_DIV;
+            onScrollInteractionBegin();
+            pageBeginMoving();
         }
     }
 
@@ -1697,12 +1687,7 @@
                 if (Math.abs(deltaX) >= 1.0f) {
                     mTouchX += deltaX;
                     mSmoothingTime = System.nanoTime() / NANOTIME_DIV;
-                    if (!mDeferScrollUpdate) {
-                        scrollBy((int) deltaX, 0);
-                        if (DEBUG) Log.d(TAG, "onTouchEvent().Scrolling: " + deltaX);
-                    } else {
-                        invalidate();
-                    }
+                    scrollBy((int) deltaX, 0);
                     mLastMotionX = x;
                     mLastMotionXRemainder = deltaX - (int) deltaX;
                 } else {
@@ -2098,7 +2083,7 @@
         snapToPage(whichPage, delta, duration);
     }
 
-    protected void snapToPage(int whichPage) {
+    public void snapToPage(int whichPage) {
         snapToPage(whichPage, getPageSnapDuration());
     }
 
@@ -2347,6 +2332,15 @@
         if (getCurrentPage() > 0) {
             info.addAction(AccessibilityNodeInfo.ACTION_SCROLL_BACKWARD);
         }
+        info.setClassName(getClass().getName());
+
+        // Accessibility-wise, PagedView doesn't support long click, so disabling it.
+        // Besides disabling the accessibility long-click, this also prevents this view from getting
+        // accessibility focus.
+        info.setLongClickable(false);
+        if (Utilities.isLmpOrAbove()) {
+            info.removeAction(AccessibilityNodeInfo.AccessibilityAction.ACTION_LONG_CLICK);
+        }
     }
 
     @Override
@@ -2360,7 +2354,7 @@
     @Override
     public void onInitializeAccessibilityEvent(AccessibilityEvent event) {
         super.onInitializeAccessibilityEvent(event);
-        event.setScrollable(true);
+        event.setScrollable(getPageCount() > 1);
     }
 
     @Override
diff --git a/src/com/android/launcher3/SmoothPagedView.java b/src/com/android/launcher3/SmoothPagedView.java
deleted file mode 100644
index 0f9b23c..0000000
--- a/src/com/android/launcher3/SmoothPagedView.java
+++ /dev/null
@@ -1,185 +0,0 @@
-/*
- * Copyright (C) 2008 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 com.android.launcher3;
-
-import android.content.Context;
-import android.util.AttributeSet;
-import android.view.animation.Interpolator;
-
-public abstract class SmoothPagedView extends PagedView {
-    private static final float SMOOTHING_SPEED = 0.75f;
-    private static final float SMOOTHING_CONSTANT = (float) (0.016 / Math.log(SMOOTHING_SPEED));
-
-    private float mBaseLineFlingVelocity;
-    private float mFlingVelocityInfluence;
-
-    static final int DEFAULT_MODE = 0;
-    static final int X_LARGE_MODE = 1;
-
-    int mScrollMode;
-
-    private Interpolator mScrollInterpolator;
-
-    public static class OvershootInterpolator implements Interpolator {
-        private static final float DEFAULT_TENSION = 1.3f;
-        private float mTension;
-
-        public OvershootInterpolator() {
-            mTension = DEFAULT_TENSION;
-        }
-
-        public void setDistance(int distance) {
-            mTension = distance > 0 ? DEFAULT_TENSION / distance : DEFAULT_TENSION;
-        }
-
-        public void disableSettle() {
-            mTension = 0.f;
-        }
-
-        public float getInterpolation(float t) {
-            t -= 1.0f;
-            return t * t * ((mTension + 1) * t + mTension) + 1.0f;
-        }
-    }
-
-    /**
-     * Used to inflate the Workspace from XML.
-     *
-     * @param context The application's context.
-     * @param attrs The attributes set containing the Workspace's customization values.
-     */
-    public SmoothPagedView(Context context, AttributeSet attrs) {
-        this(context, attrs, 0);
-    }
-
-    /**
-     * Used to inflate the Workspace from XML.
-     *
-     * @param context The application's context.
-     * @param attrs The attributes set containing the Workspace's customization values.
-     * @param defStyle Unused.
-     */
-    public SmoothPagedView(Context context, AttributeSet attrs, int defStyle) {
-        super(context, attrs, defStyle);
-
-        mUsePagingTouchSlop = false;
-
-        // This means that we'll take care of updating the scroll parameter ourselves (we do it
-        // in computeScroll), we only do this in the OVERSHOOT_MODE, ie. on phones
-        mDeferScrollUpdate = mScrollMode != X_LARGE_MODE;
-    }
-
-    protected int getScrollMode() {
-        return X_LARGE_MODE;
-    }
-
-    /**
-     * Initializes various states for this workspace.
-     */
-    @Override
-    protected void init() {
-        super.init();
-
-        mScrollMode = getScrollMode();
-        if (mScrollMode == DEFAULT_MODE) {
-            mBaseLineFlingVelocity = 2500.0f;
-            mFlingVelocityInfluence = 0.4f;
-            mScrollInterpolator = new OvershootInterpolator();
-            setDefaultInterpolator(mScrollInterpolator);
-        }
-    }
-
-    @Override
-    protected void snapToDestination() {
-        if (mScrollMode == X_LARGE_MODE) {
-            super.snapToDestination();
-        } else {
-            snapToPageWithVelocity(getPageNearestToCenterOfScreen(), 0);
-        }
-    }
-
-    @Override
-    protected void snapToPageWithVelocity(int whichPage, int velocity) {
-        if (mScrollMode == X_LARGE_MODE) {
-            super.snapToPageWithVelocity(whichPage, velocity);
-        } else {
-            snapToPageWithVelocity(whichPage, 0, true);
-        }
-    }
-
-    private void snapToPageWithVelocity(int whichPage, int velocity, boolean settle) {
-            // if (!mScroller.isFinished()) return;
-
-        whichPage = Math.max(0, Math.min(whichPage, getChildCount() - 1));
-
-        final int screenDelta = Math.max(1, Math.abs(whichPage - mCurrentPage));
-        final int newX = getScrollForPage(whichPage);
-        final int delta = newX - mUnboundedScrollX;
-        int duration = (screenDelta + 1) * 100;
-
-        if (!mScroller.isFinished()) {
-            mScroller.abortAnimation();
-        }
-
-        if (settle) {
-            ((OvershootInterpolator) mScrollInterpolator).setDistance(screenDelta);
-        } else {
-            ((OvershootInterpolator) mScrollInterpolator).disableSettle();
-        }
-
-        velocity = Math.abs(velocity);
-        if (velocity > 0) {
-            duration += (duration / (velocity / mBaseLineFlingVelocity)) * mFlingVelocityInfluence;
-        } else {
-            duration += 100;
-        }
-
-        snapToPage(whichPage, delta, duration);
-    }
-
-    @Override
-    public void snapToPage(int whichPage) {
-       if (mScrollMode == X_LARGE_MODE) {
-           super.snapToPage(whichPage);
-       } else {
-           snapToPageWithVelocity(whichPage, 0, false);
-       }
-    }
-
-    @Override
-    public void computeScroll() {
-        if (mScrollMode == X_LARGE_MODE) {
-            super.computeScroll();
-        } else {
-            boolean scrollComputed = computeScrollHelper();
-
-            if (!scrollComputed && mTouchState == TOUCH_STATE_SCROLLING) {
-                final float now = System.nanoTime() / NANOTIME_DIV;
-                final float e = (float) Math.exp((now - mSmoothingTime) / SMOOTHING_CONSTANT);
-
-                final float dx = mTouchX - mUnboundedScrollX;
-                scrollTo(Math.round(mUnboundedScrollX + dx * e), getScrollY());
-                mSmoothingTime = now;
-
-                // Keep generating points as long as we're more than 1px away from the target
-                if (dx > 1.f || dx < -1.f) {
-                    invalidate();
-                }
-            }
-        }
-    }
-}
diff --git a/src/com/android/launcher3/Utilities.java b/src/com/android/launcher3/Utilities.java
index 6c4b720..256eba0 100644
--- a/src/com/android/launcher3/Utilities.java
+++ b/src/com/android/launcher3/Utilities.java
@@ -127,6 +127,11 @@
         return Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP;
     }
 
+    public static boolean isLmpMR1OrAbove() {
+        // TODO(adamcohen): update to Build.VERSION_CODES.LOLLIPOP_MR1 once building against 22;
+        return Build.VERSION.SDK_INT >= 22;
+    }
+
     static Bitmap createIconBitmap(Cursor c, int iconIndex, Context context) {
         byte[] data = c.getBlob(iconIndex);
         try {
@@ -588,7 +593,6 @@
     }
 
     public static final Comparator<ItemInfo> RANK_COMPARATOR = new Comparator<ItemInfo>() {
-
         @Override
         public int compare(ItemInfo lhs, ItemInfo rhs) {
             return lhs.rank - rhs.rank;
diff --git a/src/com/android/launcher3/Workspace.java b/src/com/android/launcher3/Workspace.java
index d2c37d2..6d5affb 100644
--- a/src/com/android/launcher3/Workspace.java
+++ b/src/com/android/launcher3/Workspace.java
@@ -64,8 +64,8 @@
 import com.android.launcher3.LauncherSettings.Favorites;
 import com.android.launcher3.UninstallDropTarget.UninstallSource;
 import com.android.launcher3.accessibility.LauncherAccessibilityDelegate;
-import com.android.launcher3.accessibility.OverviewScreenAccessibilityDelegate;
 import com.android.launcher3.accessibility.LauncherAccessibilityDelegate.AccessibilityDragSource;
+import com.android.launcher3.accessibility.OverviewScreenAccessibilityDelegate;
 import com.android.launcher3.compat.UserHandleCompat;
 import com.android.launcher3.util.LongArrayMap;
 import com.android.launcher3.util.Thunk;
@@ -83,12 +83,14 @@
  * Each page contains a number of icons, folders or widgets the user can
  * interact with. A workspace is meant to be used with a fixed width only.
  */
-public class Workspace extends SmoothPagedView
+public class Workspace extends PagedView
         implements DropTarget, DragSource, DragScroller, View.OnTouchListener,
         DragController.DragListener, LauncherTransitionable, ViewGroup.OnHierarchyChangeListener,
         Insettable, UninstallSource, AccessibilityDragSource {
     private static final String TAG = "Launcher.Workspace";
 
+    private static boolean ENFORCE_DRAG_EVENT_ORDER = false;
+
     protected static final int SNAP_OFF_EMPTY_SCREEN_DURATION = 400;
     protected static final int FADE_EMPTY_SCREEN_DURATION = 150;
 
@@ -215,7 +217,6 @@
     private FolderIcon mDragOverFolderIcon = null;
     private boolean mCreateUserFolderOnDrop = false;
     private boolean mAddToExistingFolderOnDrop = false;
-    private DropTarget.DragEnforcer mDragEnforcer;
     private float mMaxDistanceForFolderCreation;
 
     private final Canvas mCanvas = new Canvas();
@@ -301,9 +302,6 @@
 
         mOutlineHelper = HolographicOutlineHelper.obtain(context);
 
-        mDragEnforcer = new DropTarget.DragEnforcer(context);
-        // With workspace, data is available straight from the get-go
-
         mLauncher = (Launcher) context;
         mStateTransitionAnimation = new WorkspaceStateTransitionAnimation(mLauncher, this);
         final Resources res = getResources();
@@ -327,7 +325,6 @@
 
         // Disable multitouch across the workspace/all apps/customize tray
         setMotionEventSplittingEnabled(true);
-        setImportantForAccessibility(View.IMPORTANT_FOR_ACCESSIBILITY_YES);
     }
 
     @Override
@@ -372,22 +369,23 @@
         return r;
     }
 
+    @Override
     public void onDragStart(final DragSource source, Object info, int dragAction) {
+        if (ENFORCE_DRAG_EVENT_ORDER) {
+            enfoceDragParity("onDragStart", 0, 0);
+        }
+
         mIsDragOccuring = true;
         updateChildrenLayersEnabled(false);
         mLauncher.lockScreenOrientation();
         mLauncher.onInteractionBegin();
         // Prevent any Un/InstallShortcutReceivers from updating the db while we are dragging
         InstallShortcutReceiver.enableInstallQueue();
-        post(new Runnable() {
-            @Override
-            public void run() {
-                if (mIsDragOccuring && mAddNewPageOnDrag) {
-                    mDeferRemoveExtraEmptyScreen = false;
-                    addExtraEmptyScreenOnDrag();
-                }
-            }
-        });
+
+        if (mAddNewPageOnDrag) {
+            mDeferRemoveExtraEmptyScreen = false;
+            addExtraEmptyScreenOnDrag();
+        }
     }
 
     public void setAddNewPageOnDrag(boolean addPage) {
@@ -398,7 +396,12 @@
         mDeferRemoveExtraEmptyScreen = true;
     }
 
+    @Override
     public void onDragEnd() {
+        if (ENFORCE_DRAG_EVENT_ORDER) {
+            enfoceDragParity("onDragEnd", 0, 0);
+        }
+
         if (!mDeferRemoveExtraEmptyScreen) {
             removeExtraEmptyScreen(true, mDragSourceInternal != null);
         }
@@ -458,11 +461,6 @@
     }
 
     @Override
-    protected int getScrollMode() {
-        return SmoothPagedView.X_LARGE_MODE;
-    }
-
-    @Override
     public void onChildViewAdded(View parent, View child) {
         if (!(child instanceof CellLayout)) {
             throw new IllegalArgumentException("A Workspace can only have CellLayout children.");
@@ -736,6 +734,7 @@
                 fadeAndRemoveEmptyScreen(SNAP_OFF_EMPTY_SCREEN_DURATION, FADE_EMPTY_SCREEN_DURATION,
                         onComplete, stripEmptyScreens);
             } else {
+                snapToPage(getNextPage(), 0);
                 fadeAndRemoveEmptyScreen(0, FADE_EMPTY_SCREEN_DURATION,
                         onComplete, stripEmptyScreens);
             }
@@ -2019,14 +2018,9 @@
             for (int i = numCustomPages(); i < total; i++) {
                 updateAccessibilityFlags((CellLayout) getPageAt(i), i);
             }
-            if (mState == State.NORMAL) {
-                setImportantForAccessibility(IMPORTANT_FOR_ACCESSIBILITY_NO);
-            } else {
-                setImportantForAccessibility(IMPORTANT_FOR_ACCESSIBILITY_YES);
-            }
         } else {
             int accessible = mState == State.NORMAL ?
-                    IMPORTANT_FOR_ACCESSIBILITY_NO :
+                    IMPORTANT_FOR_ACCESSIBILITY_AUTO :
                         IMPORTANT_FOR_ACCESSIBILITY_NO_HIDE_DESCENDANTS;
             setImportantForAccessibility(accessible);
         }
@@ -2045,7 +2039,7 @@
             page.setAccessibilityDelegate(mPagesAccessibilityDelegate);
         } else {
             int accessible = mState == State.NORMAL ?
-                    IMPORTANT_FOR_ACCESSIBILITY_NO :
+                    IMPORTANT_FOR_ACCESSIBILITY_AUTO :
                         IMPORTANT_FOR_ACCESSIBILITY_NO_HIDE_DESCENDANTS;
             page.setImportantForAccessibility(IMPORTANT_FOR_ACCESSIBILITY_NO);
             page.getShortcutsAndWidgets().setImportantForAccessibility(accessible);
@@ -2827,8 +2821,12 @@
         location[1] = vY - y;
     }
 
+    @Override
     public void onDragEnter(DragObject d) {
-        mDragEnforcer.onDragEnter();
+        if (ENFORCE_DRAG_EVENT_ORDER) {
+            enfoceDragParity("onDragEnter", 1, 1);
+        }
+
         mCreateUserFolderOnDrop = false;
         mAddToExistingFolderOnDrop = false;
 
@@ -2881,8 +2879,11 @@
         return null;
     }
 
+    @Override
     public void onDragExit(DragObject d) {
-        mDragEnforcer.onDragExit();
+        if (ENFORCE_DRAG_EVENT_ORDER) {
+            enfoceDragParity("onDragExit", -1, 0);
+        }
 
         // Here we store the final page that will be dropped to, if the workspace in fact
         // receives the drop
@@ -2914,6 +2915,24 @@
         mLauncher.getDragLayer().hidePageHints();
     }
 
+    private void enfoceDragParity(String event, int update, int expectedValue) {
+        enfoceDragParity(this, event, update, expectedValue);
+        for (int i = 0; i < getChildCount(); i++) {
+            enfoceDragParity(getChildAt(i), event, update, expectedValue);
+        }
+    }
+
+    private void enfoceDragParity(View v, String event, int update, int expectedValue) {
+        Object tag = v.getTag(R.id.drag_event_parity);
+        int value = tag == null ? 0 : (Integer) tag;
+        value += update;
+        v.setTag(R.id.drag_event_parity, value);
+
+        if (value != expectedValue) {
+            Log.e(TAG, event + ": Drag contract violated: " + value);
+        }
+    }
+
     void setCurrentDropLayout(CellLayout layout) {
         if (mDragTargetLayout != null) {
             mDragTargetLayout.revertTempState();
diff --git a/src/com/android/launcher3/allapps/AllAppsContainerView.java b/src/com/android/launcher3/allapps/AllAppsContainerView.java
index 60f9ab3..d81f97f 100644
--- a/src/com/android/launcher3/allapps/AllAppsContainerView.java
+++ b/src/com/android/launcher3/allapps/AllAppsContainerView.java
@@ -447,7 +447,6 @@
     @Override
     protected void onFixedBoundsUpdated() {
         // Update the number of items in the grid
-        LauncherAppState app = LauncherAppState.getInstance();
         DeviceProfile grid = mLauncher.getDeviceProfile();
         if (grid.updateAppsViewNumCols(getContext().getResources(), mFixedBounds.width())) {
             mNumAppsPerRow = grid.allAppsNumCols;
diff --git a/src/com/android/launcher3/allapps/AllAppsRecyclerView.java b/src/com/android/launcher3/allapps/AllAppsRecyclerView.java
index e95fa32..cc5add3 100644
--- a/src/com/android/launcher3/allapps/AllAppsRecyclerView.java
+++ b/src/com/android/launcher3/allapps/AllAppsRecyclerView.java
@@ -15,75 +15,34 @@
  */
 package com.android.launcher3.allapps;
 
-import android.animation.ObjectAnimator;
 import android.content.Context;
-import android.content.res.Resources;
-import android.graphics.Canvas;
-import android.graphics.Color;
-import android.graphics.Paint;
 import android.graphics.Rect;
 import android.graphics.drawable.Drawable;
 import android.support.v7.widget.LinearLayoutManager;
 import android.support.v7.widget.RecyclerView;
 import android.util.AttributeSet;
-import android.view.MotionEvent;
 import android.view.View;
-import android.view.ViewConfiguration;
+
 import com.android.launcher3.BaseRecyclerView;
 import com.android.launcher3.DeviceProfile;
 import com.android.launcher3.Launcher;
-import com.android.launcher3.R;
 import com.android.launcher3.Utilities;
 
 import java.util.List;
 
 /**
- * A RecyclerView with custom fastscroll support.  This is the main container for the all apps
- * icons.
+ * A RecyclerView with custom fast scroll support for the all apps view.
  */
 public class AllAppsRecyclerView extends BaseRecyclerView {
 
-    /**
-     * The current scroll state of the recycler view.  We use this in updateVerticalScrollbarBounds()
-     * and scrollToPositionAtProgress() to determine the scroll position of the recycler view so
-     * that we can calculate what the scroll bar looks like, and where to jump to from the fast
-     * scroller.
-     */
-    private static class ScrollPositionState {
-        // The index of the first visible row
-        int rowIndex;
-        // The offset of the first visible row
-        int rowTopOffset;
-        // The height of a given row (they are currently all the same height)
-        int rowHeight;
-    }
-
-    private static final float FAST_SCROLL_OVERLAY_Y_OFFSET_FACTOR = 1.5f;
-
     private AlphabeticalAppsList mApps;
     private int mNumAppsPerRow;
     private int mNumPredictedAppsPerRow;
 
-    private Drawable mScrollbar;
-    private Drawable mFastScrollerBg;
-    private Rect mTmpFastScrollerInvalidateRect = new Rect();
-    private Rect mFastScrollerBounds = new Rect();
-    private Rect mVerticalScrollbarBounds = new Rect();
-    private boolean mDraggingFastScroller;
-    private String mFastScrollSectionName;
-    private Paint mFastScrollTextPaint;
-    private Rect mFastScrollTextBounds = new Rect();
-    private float mFastScrollAlpha;
     private int mPredictionBarHeight;
-    private int mDownX;
-    private int mDownY;
-    private int mLastX;
-    private int mLastY;
-    private int mScrollbarWidth;
     private int mScrollbarMinHeight;
-    private int mScrollbarInset;
+
     private Rect mBackgroundPadding = new Rect();
-    private ScrollPositionState mScrollPosState = new ScrollPositionState();
 
     private Launcher mLauncher;
 
@@ -102,25 +61,7 @@
     public AllAppsRecyclerView(Context context, AttributeSet attrs, int defStyleAttr,
             int defStyleRes) {
         super(context, attrs, defStyleAttr);
-
         mLauncher = (Launcher) context;
-        Resources res = context.getResources();
-        int fastScrollerSize = res.getDimensionPixelSize(R.dimen.all_apps_fast_scroll_popup_size);
-        mScrollbar = res.getDrawable(R.drawable.all_apps_scrollbar_thumb);
-        mFastScrollerBg = res.getDrawable(R.drawable.all_apps_fastscroll_bg);
-        mFastScrollerBg.setBounds(0, 0, fastScrollerSize, fastScrollerSize);
-        mFastScrollTextPaint = new Paint();
-        mFastScrollTextPaint.setColor(Color.WHITE);
-        mFastScrollTextPaint.setAntiAlias(true);
-        mFastScrollTextPaint.setTextSize(res.getDimensionPixelSize(
-                R.dimen.all_apps_fast_scroll_text_size));
-        mScrollbarWidth = res.getDimensionPixelSize(R.dimen.all_apps_fast_scroll_bar_width);
-        mScrollbarMinHeight =
-                res.getDimensionPixelSize(R.dimen.all_apps_fast_scroll_bar_min_height);
-        mScrollbarInset =
-                res.getDimensionPixelSize(R.dimen.all_apps_fast_scroll_scrubber_touch_inset);
-        setFastScrollerAlpha(getFastScrollerAlpha());
-        setOverScrollMode(View.OVER_SCROLL_NEVER);
     }
 
     /**
@@ -158,28 +99,6 @@
     }
 
     /**
-     * Sets the fast scroller alpha.
-     */
-    public void setFastScrollerAlpha(float alpha) {
-        mFastScrollAlpha = alpha;
-        invalidateFastScroller(mFastScrollerBounds);
-    }
-
-    /**
-     * Gets the fast scroller alpha.
-     */
-    public float getFastScrollerAlpha() {
-        return mFastScrollAlpha;
-    }
-
-    /**
-     * Returns the scroll bar width.
-     */
-    public int getScrollbarWidth() {
-        return mScrollbarWidth;
-    }
-
-    /**
      * Scrolls this recycler view to the top.
      */
     public void scrollToTop() {
@@ -191,11 +110,11 @@
      */
     public int getScrollPosition() {
         List<AlphabeticalAppsList.AdapterItem> items = mApps.getAdapterItems();
-        getCurScrollState(mScrollPosState, items);
-        if (mScrollPosState.rowIndex != -1) {
+        getCurScrollState(scrollPosState, items);
+        if (scrollPosState.rowIndex != -1) {
             int predictionBarHeight = mApps.getPredictedApps().isEmpty() ? 0 : mPredictionBarHeight;
-            return getPaddingTop() + (mScrollPosState.rowIndex * mScrollPosState.rowHeight) +
-                    predictionBarHeight - mScrollPosState.rowTopOffset;
+            return getPaddingTop() + (scrollPosState.rowIndex * scrollPosState.rowHeight) +
+                    predictionBarHeight - scrollPosState.rowTopOffset;
         }
         return 0;
     }
@@ -206,150 +125,11 @@
         addOnItemTouchListener(this);
     }
 
-    @Override
-    protected void dispatchDraw(Canvas canvas) {
-        super.dispatchDraw(canvas);
-        drawVerticalScrubber(canvas);
-        drawFastScrollerPopup(canvas);
-    }
-
-    /**
-     * We intercept the touch handling only to support fast scrolling when initiated from the
-     * scroll bar.  Otherwise, we fall back to the default RecyclerView touch handling.
-     */
-    @Override
-    public boolean onInterceptTouchEvent(RecyclerView rv, MotionEvent ev) {
-        return handleTouchEvent(ev);
-    }
-
-    @Override
-    public void onTouchEvent(RecyclerView rv, MotionEvent ev) {
-        handleTouchEvent(ev);
-    }
-
-    /**
-     * Handles the touch event and determines whether to show the fast scroller (or updates it if
-     * it is already showing).
-     */
-    private boolean handleTouchEvent(MotionEvent ev) {
-        ViewConfiguration config = ViewConfiguration.get(getContext());
-
-        int action = ev.getAction();
-        int x = (int) ev.getX();
-        int y = (int) ev.getY();
-        switch (action) {
-            case MotionEvent.ACTION_DOWN:
-                // Keep track of the down positions
-                mDownX = mLastX = x;
-                mDownY = mLastY = y;
-                if (shouldStopScroll(ev)) {
-                    stopScroll();
-                }
-                break;
-            case MotionEvent.ACTION_MOVE:
-                // Check if we are scrolling
-                if (!mDraggingFastScroller && isPointNearScrollbar(mDownX, mDownY) &&
-                        Math.abs(y - mDownY) > config.getScaledTouchSlop()) {
-                    getParent().requestDisallowInterceptTouchEvent(true);
-                    mDraggingFastScroller = true;
-                    animateFastScrollerVisibility(true);
-                }
-                if (mDraggingFastScroller) {
-                    mLastX = x;
-                    mLastY = y;
-
-                    // Scroll to the right position, and update the section name
-                    int top = getPaddingTop() + (mFastScrollerBg.getBounds().height() / 2);
-                    int bottom = getHeight() - getPaddingBottom() -
-                            (mFastScrollerBg.getBounds().height() / 2);
-                    float boundedY = (float) Math.max(top, Math.min(bottom, y));
-                    mFastScrollSectionName = scrollToPositionAtProgress((boundedY - top) /
-                            (bottom - top));
-
-                    // Combine the old and new fast scroller bounds to create the full invalidate
-                    // rect
-                    mTmpFastScrollerInvalidateRect.set(mFastScrollerBounds);
-                    updateFastScrollerBounds();
-                    mTmpFastScrollerInvalidateRect.union(mFastScrollerBounds);
-                    invalidateFastScroller(mTmpFastScrollerInvalidateRect);
-                }
-                break;
-            case MotionEvent.ACTION_UP:
-            case MotionEvent.ACTION_CANCEL:
-                mDraggingFastScroller = false;
-                animateFastScrollerVisibility(false);
-                break;
-        }
-        return mDraggingFastScroller;
-    }
-
-    /**
-     * Animates the visibility of the fast scroller popup.
-     */
-    private void animateFastScrollerVisibility(boolean visible) {
-        ObjectAnimator anim = ObjectAnimator.ofFloat(this, "fastScrollerAlpha", visible ? 1f : 0f);
-        anim.setDuration(visible ? 200 : 150);
-        anim.start();
-    }
-
-    /**
-     * Returns whether a given point is near the scrollbar.
-     */
-    private boolean isPointNearScrollbar(int x, int y) {
-        // Check if we are scrolling
-        updateVerticalScrollbarBounds();
-        mVerticalScrollbarBounds.inset(mScrollbarInset, mScrollbarInset);
-        return mVerticalScrollbarBounds.contains(x, y);
-    }
-
-    /**
-     * Draws the fast scroller popup.
-     */
-    private void drawFastScrollerPopup(Canvas canvas) {
-        if (mFastScrollAlpha > 0f && !mFastScrollSectionName.isEmpty()) {
-            // Draw the fast scroller popup
-            int restoreCount = canvas.save(Canvas.MATRIX_SAVE_FLAG);
-            canvas.translate(mFastScrollerBounds.left, mFastScrollerBounds.top);
-            mFastScrollerBg.setAlpha((int) (mFastScrollAlpha * 255));
-            mFastScrollerBg.draw(canvas);
-            mFastScrollTextPaint.setAlpha((int) (mFastScrollAlpha * 255));
-            mFastScrollTextPaint.getTextBounds(mFastScrollSectionName, 0,
-                    mFastScrollSectionName.length(), mFastScrollTextBounds);
-            float textWidth = mFastScrollTextPaint.measureText(mFastScrollSectionName);
-            canvas.drawText(mFastScrollSectionName,
-                    (mFastScrollerBounds.width() - textWidth) / 2,
-                    mFastScrollerBounds.height() -
-                            (mFastScrollerBounds.height() - mFastScrollTextBounds.height()) / 2,
-                    mFastScrollTextPaint);
-            canvas.restoreToCount(restoreCount);
-        }
-    }
-
-    /**
-     * Draws the vertical scrollbar.
-     */
-    private void drawVerticalScrubber(Canvas canvas) {
-        updateVerticalScrollbarBounds();
-
-        // Draw the scroll bar
-        int restoreCount = canvas.save(Canvas.MATRIX_SAVE_FLAG);
-        canvas.translate(mVerticalScrollbarBounds.left, mVerticalScrollbarBounds.top);
-        mScrollbar.setBounds(0, 0, mScrollbarWidth, mVerticalScrollbarBounds.height());
-        mScrollbar.draw(canvas);
-        canvas.restoreToCount(restoreCount);
-    }
-
-    /**
-     * Invalidates the fast scroller popup.
-     */
-    private void invalidateFastScroller(Rect bounds) {
-        invalidate(bounds.left, bounds.top, bounds.right, bounds.bottom);
-    }
-
     /**
      * Maps the touch (from 0..1) to the adapter position that should be visible.
      */
-    private String scrollToPositionAtProgress(float touchFraction) {
+    @Override
+    public String scrollToPositionAtProgress(float touchFraction) {
         // Ensure that we have any sections
         List<AlphabeticalAppsList.FastScrollSectionInfo> fastScrollSections =
                 mApps.getFastScrollerSections();
@@ -393,77 +173,6 @@
         return lastScrollSection.sectionName;
     }
 
-    /**
-     * Updates the bounds for the scrollbar.
-     */
-    private void updateVerticalScrollbarBounds() {
-        List<AlphabeticalAppsList.AdapterItem> items = mApps.getAdapterItems();
-
-        // Skip early if there are no items
-        if (items.isEmpty()) {
-            mVerticalScrollbarBounds.setEmpty();
-            return;
-        }
-
-        // Find the index and height of the first visible row (all rows have the same height)
-        int x;
-        int y;
-        int predictionBarHeight = mApps.getPredictedApps().isEmpty() ? 0 : mPredictionBarHeight;
-        int rowCount = getNumRows();
-        getCurScrollState(mScrollPosState, items);
-        if (mScrollPosState.rowIndex != -1) {
-            int height = getHeight() - getPaddingTop() - getPaddingBottom();
-            int totalScrollHeight = rowCount * mScrollPosState.rowHeight + predictionBarHeight;
-            if (totalScrollHeight > height) {
-                int scrollbarHeight = Math.max(mScrollbarMinHeight,
-                        (int) (height / ((float) totalScrollHeight / height)));
-
-                // Calculate the position and size of the scroll bar
-                if (Utilities.isRtl(getResources())) {
-                    x = mBackgroundPadding.left;
-                } else {
-                    x = getWidth() - mBackgroundPadding.right - mScrollbarWidth;
-                }
-
-                // To calculate the offset, we compute the percentage of the total scrollable height
-                // that the user has already scrolled and then map that to the scroll bar bounds
-                int availableY = totalScrollHeight - height;
-                int availableScrollY = height - scrollbarHeight;
-                y = (mScrollPosState.rowIndex * mScrollPosState.rowHeight) + predictionBarHeight
-                        - mScrollPosState.rowTopOffset;
-                y = getPaddingTop() +
-                        (int) (((float) (getPaddingTop() + y) / availableY) * availableScrollY);
-
-                mVerticalScrollbarBounds.set(x, y, x + mScrollbarWidth, y + scrollbarHeight);
-                return;
-            }
-        }
-        mVerticalScrollbarBounds.setEmpty();
-    }
-
-    /**
-     * Updates the bounds for the fast scroller.
-     */
-    private void updateFastScrollerBounds() {
-        if (mFastScrollAlpha > 0f && !mFastScrollSectionName.isEmpty()) {
-            int x;
-            int y;
-
-            // Calculate the position for the fast scroller popup
-            Rect bgBounds = mFastScrollerBg.getBounds();
-            if (Utilities.isRtl(getResources())) {
-                x = mBackgroundPadding.left + getScrollBarSize();
-            } else {
-                x = getWidth() - getPaddingRight() - getScrollBarSize() - bgBounds.width();
-            }
-            y = mLastY - (int) (FAST_SCROLL_OVERLAY_Y_OFFSET_FACTOR * bgBounds.height());
-            y = Math.max(getPaddingTop(), Math.min(y, getHeight() - getPaddingBottom() -
-                    bgBounds.height()));
-            mFastScrollerBounds.set(x, y, x + bgBounds.width(), y + bgBounds.height());
-        } else {
-            mFastScrollerBounds.setEmpty();
-        }
-    }
 
     /**
      * Returns the row index for a app index in the list.
@@ -496,6 +205,55 @@
         return rowCount;
     }
 
+
+    /**
+     * Updates the bounds for the scrollbar.
+     */
+    @Override
+    public void updateVerticalScrollbarBounds() {
+        List<AlphabeticalAppsList.AdapterItem> items = mApps.getAdapterItems();
+
+        // Skip early if there are no items.
+        if (items.isEmpty()) {
+            verticalScrollbarBounds.setEmpty();
+            return;
+        }
+
+        // Find the index and height of the first visible row (all rows have the same height)
+        int x, y;
+        int predictionBarHeight = mApps.getPredictedApps().isEmpty() ? 0 : mPredictionBarHeight;
+        int rowCount = getNumRows();
+        getCurScrollState(scrollPosState, items);
+        if (scrollPosState.rowIndex != -1) {
+            int height = getHeight() - getPaddingTop() - getPaddingBottom();
+            int totalScrollHeight = rowCount * scrollPosState.rowHeight + predictionBarHeight;
+            if (totalScrollHeight > height) {
+                int scrollbarHeight = Math.max(mScrollbarMinHeight,
+                        (int) (height / ((float) totalScrollHeight / height)));
+
+                // Calculate the position and size of the scroll bar
+                if (Utilities.isRtl(getResources())) {
+                    x = mBackgroundPadding.left;
+                } else {
+                    x = getWidth() - mBackgroundPadding.right - getScrollbarWidth();
+                }
+
+                // To calculate the offset, we compute the percentage of the total scrollable height
+                // that the user has already scrolled and then map that to the scroll bar bounds
+                int availableY = totalScrollHeight - height;
+                int availableScrollY = height - scrollbarHeight;
+                y = (scrollPosState.rowIndex * scrollPosState.rowHeight) + predictionBarHeight
+                        - scrollPosState.rowTopOffset;
+                y = getPaddingTop() +
+                        (int) (((float) (getPaddingTop() + y) / availableY) * availableScrollY);
+
+                verticalScrollbarBounds.set(x, y, x + getScrollbarWidth(), y + scrollbarHeight);
+                return;
+            }
+        }
+        verticalScrollbarBounds.setEmpty();
+    }
+
     /**
      * Returns the current scroll state.
      */
diff --git a/src/com/android/launcher3/util/RevealOutlineProvider.java b/src/com/android/launcher3/util/RevealOutlineProvider.java
new file mode 100644
index 0000000..0db3984
--- /dev/null
+++ b/src/com/android/launcher3/util/RevealOutlineProvider.java
@@ -0,0 +1,49 @@
+package com.android.launcher3.util;
+
+import android.annotation.TargetApi;
+import android.graphics.Outline;
+import android.graphics.Rect;
+import android.os.Build;
+import android.view.View;
+import android.view.ViewOutlineProvider;
+
+@TargetApi(Build.VERSION_CODES.LOLLIPOP)
+public class RevealOutlineProvider extends ViewOutlineProvider {
+
+    private int mCenterX;
+    private int mCenterY;
+    private float mRadius0;
+    private float mRadius1;
+    private int mCurrentRadius;
+
+    private final Rect mOval;
+
+    /**
+     * @param x reveal center x
+     * @param y reveal center y
+     * @param r0 initial radius
+     * @param r1 final radius
+     */
+    public RevealOutlineProvider(int x, int y, float r0, float r1) {
+        mCenterX = x;
+        mCenterY = y;
+        mRadius0 = r0;
+        mRadius1 = r1;
+
+        mOval = new Rect();
+    }
+
+    public void setProgress(float progress) {
+        mCurrentRadius = (int) ((1 - progress) * mRadius0 + progress * mRadius1);
+
+        mOval.left = mCenterX - mCurrentRadius;
+        mOval.top = mCenterY - mCurrentRadius;
+        mOval.right = mCenterX + mCurrentRadius;
+        mOval.bottom = mCenterY + mCurrentRadius;
+    }
+
+    @Override
+    public void getOutline(View v, Outline outline) {
+        outline.setRoundRect(mOval, mCurrentRadius);
+    }
+}
diff --git a/src/com/android/launcher3/util/UiThreadCircularReveal.java b/src/com/android/launcher3/util/UiThreadCircularReveal.java
new file mode 100644
index 0000000..c7324fb
--- /dev/null
+++ b/src/com/android/launcher3/util/UiThreadCircularReveal.java
@@ -0,0 +1,55 @@
+package com.android.launcher3.util;
+
+import android.animation.Animator;
+import android.animation.AnimatorListenerAdapter;
+import android.animation.ValueAnimator;
+import android.animation.ValueAnimator.AnimatorUpdateListener;
+import android.annotation.TargetApi;
+import android.os.Build;
+import android.view.View;
+import android.view.ViewOutlineProvider;
+
+import com.android.launcher3.Utilities;
+
+@TargetApi(Build.VERSION_CODES.LOLLIPOP)
+public class UiThreadCircularReveal {
+
+    public static ValueAnimator createCircularReveal(View v, int x, int y, float r0, float r1) {
+        ValueAnimator va = ValueAnimator.ofFloat(0f, 1f);
+
+        final View revealView = v;
+        final RevealOutlineProvider outlineProvider = new RevealOutlineProvider(x, y, r0, r1);
+        final ViewOutlineProvider originalProvider = revealView.getOutlineProvider();
+        final float elevation = v.getElevation();
+
+        va.addListener(new AnimatorListenerAdapter() {
+            public void onAnimationStart(Animator animation) {
+                revealView.setOutlineProvider(outlineProvider);
+                revealView.setClipToOutline(true);
+                revealView.setTranslationZ(-elevation);
+            }
+
+            public void onAnimationEnd(Animator animation) {
+                revealView.setOutlineProvider(originalProvider);
+                revealView.setClipToOutline(false);
+                revealView.setTranslationZ(0);
+            }
+
+        });
+
+        va.addUpdateListener(new AnimatorUpdateListener() {
+            @Override
+            public void onAnimationUpdate(ValueAnimator arg0) {
+                float progress = arg0.getAnimatedFraction();
+                outlineProvider.setProgress(progress);
+                if (Utilities.isLmpMR1OrAbove()) {
+                    revealView.invalidateOutline();
+                } else {
+                    // On L, a bug requires calling a full view invalidate.
+                    revealView.invalidate();
+                }
+            }
+        });
+        return va;
+    }
+}
diff --git a/src/com/android/launcher3/widget/WidgetsContainerView.java b/src/com/android/launcher3/widget/WidgetsContainerView.java
index 05e842e..11c2107 100644
--- a/src/com/android/launcher3/widget/WidgetsContainerView.java
+++ b/src/com/android/launcher3/widget/WidgetsContainerView.java
@@ -35,7 +35,6 @@
 import com.android.launcher3.DragController;
 import com.android.launcher3.DragSource;
 import com.android.launcher3.DropTarget.DragObject;
-import com.android.launcher3.model.WidgetsModel;
 import com.android.launcher3.Folder;
 import com.android.launcher3.IconCache;
 import com.android.launcher3.ItemInfo;
@@ -46,6 +45,7 @@
 import com.android.launcher3.Utilities;
 import com.android.launcher3.WidgetPreviewLoader;
 import com.android.launcher3.Workspace;
+import com.android.launcher3.model.WidgetsModel;
 
 /**
  * The widgets list view container.
@@ -56,8 +56,6 @@
     private static final String TAG = "WidgetsContainerView";
     private static final boolean DEBUG = false;
 
-    private static final int SPRING_MODE_DELAY_MS = 150;
-
     /* Coefficient multiplied to the screen height for preloading widgets. */
     private static final int PRELOAD_SCREEN_HEIGHT_MULTIPLE = 1;
 
@@ -67,7 +65,7 @@
     private IconCache mIconCache;
 
     /* Recycler view related member variables */
-    private RecyclerView mView;
+    private WidgetsRecyclerView mView;
     private WidgetsListAdapter mAdapter;
 
     /* Touch handling related member variables. */
@@ -102,7 +100,7 @@
 
     @Override
     protected void onFinishInflate() {
-        mView = (RecyclerView) findViewById(R.id.widgets_list_view);
+        mView = (WidgetsRecyclerView) findViewById(R.id.widgets_list_view);
         mView.setAdapter(mAdapter);
 
         // This extends the layout space so that preloading happen for the {@link RecyclerView}
@@ -186,18 +184,11 @@
             Log.e(TAG, "Unexpected dragging view: " + v);
         }
 
-        // We delay entering spring-loaded mode slightly to make sure the UI
-        // thread is free of any work.
-        postDelayed(new Runnable() {
-            @Override
-            public void run() {
-                // We don't enter spring-loaded mode if the drag has been cancelled
-                if (mLauncher.getDragController().isDragging()) {
-                    // Go into spring loaded mode (must happen before we startDrag())
-                    mLauncher.enterSpringLoadedDragMode();
-                }
-            }
-        }, SPRING_MODE_DELAY_MS);
+        // We don't enter spring-loaded mode if the drag has been cancelled
+        if (mLauncher.getDragController().isDragging()) {
+            // Go into spring loaded mode (must happen before we startDrag())
+            mLauncher.enterSpringLoadedDragMode();
+        }
 
         return true;
     }
@@ -360,6 +351,7 @@
      * Initialize the widget data model.
      */
     public void addWidgets(WidgetsModel model) {
+        mView.setWidgets(model);
         mAdapter.setWidgetsModel(model);
         mAdapter.notifyDataSetChanged();
     }
diff --git a/src/com/android/launcher3/widget/WidgetsListAdapter.java b/src/com/android/launcher3/widget/WidgetsListAdapter.java
index 7439a44..e82c0a6 100644
--- a/src/com/android/launcher3/widget/WidgetsListAdapter.java
+++ b/src/com/android/launcher3/widget/WidgetsListAdapter.java
@@ -32,7 +32,6 @@
 
 import com.android.launcher3.BubbleTextView;
 import com.android.launcher3.DeviceProfile;
-import com.android.launcher3.IconCache;
 import com.android.launcher3.Launcher;
 import com.android.launcher3.LauncherAppState;
 import com.android.launcher3.LauncherAppWidgetProviderInfo;
diff --git a/src/com/android/launcher3/widget/WidgetsRecyclerView.java b/src/com/android/launcher3/widget/WidgetsRecyclerView.java
index 31ef5d6..bef2559 100644
--- a/src/com/android/launcher3/widget/WidgetsRecyclerView.java
+++ b/src/com/android/launcher3/widget/WidgetsRecyclerView.java
@@ -17,14 +17,23 @@
 package com.android.launcher3.widget;
 
 import android.content.Context;
+import android.graphics.Rect;
+import android.graphics.drawable.Drawable;
+import android.support.v7.widget.RecyclerView;
 import android.util.AttributeSet;
+import android.view.MotionEvent;
+
 import com.android.launcher3.BaseRecyclerView;
+import com.android.launcher3.model.WidgetsModel;
 
 /**
  * The widgets recycler view.
  */
 public class WidgetsRecyclerView extends BaseRecyclerView {
 
+    private WidgetsModel mWidgets;
+    private Rect mBackgroundPadding = new Rect();
+
     public WidgetsRecyclerView(Context context) {
         this(context, null);
     }
@@ -37,4 +46,67 @@
         super(context, attrs, defStyleAttr);
     }
 
+    @Override
+    protected void onFinishInflate() {
+        super.onFinishInflate();
+        addOnItemTouchListener(this);
+    }
+
+    public void updateBackgroundPadding(Drawable background) {
+        background.getPadding(mBackgroundPadding);
+    }
+
+    /**
+     * Sets the widget model in this view, used to determine the fast scroll position.
+     */
+    public void setWidgets(WidgetsModel widgets) {
+        mWidgets = widgets;
+    }
+
+    /**
+     * Maps the touch (from 0..1) to the adapter position that should be visible.
+     */
+    @Override
+    public String scrollToPositionAtProgress(float touchFraction) {
+        // Ensure that we have any sections
+        return "";
+    }
+
+    /**
+     * Updates the bounds for the scrollbar.
+     */
+    @Override
+    public void updateVerticalScrollbarBounds() {
+        int rowCount = mWidgets.getPackageSize();
+
+        // Skip early if there are no items.
+        if (rowCount == 0) {
+            verticalScrollbarBounds.setEmpty();
+            return;
+        }
+
+        int x, y;
+        getCurScrollState(scrollPosState);
+        if (scrollPosState.rowIndex < 0) {
+            verticalScrollbarBounds.setEmpty();
+        }
+        // TODO
+    }
+
+    /**
+     * Returns the current scroll state.
+     */
+    private void getCurScrollState(ScrollPositionState stateOut) {
+        stateOut.rowIndex = -1;
+        stateOut.rowTopOffset = -1;
+        stateOut.rowHeight = -1;
+
+        int rowCount = mWidgets.getPackageSize();
+
+        // Return early if there are no items
+        if (rowCount == 0) {
+            return;
+        }
+        // TODO
+    }
 }
\ No newline at end of file