Adding graphic for all apps empty search screen.

Change-Id: I976a327a5984790c458b0f36d33c0b1ac16ec59c
diff --git a/proguard.flags b/proguard.flags
index e6c4c51..5a3dfd1 100644
--- a/proguard.flags
+++ b/proguard.flags
@@ -2,6 +2,11 @@
   *;
 }
 
+-keep class com.android.launcher3.allapps.AllAppsBackgroundDrawable {
+  public void setAlpha(int);
+  public int getAlpha();
+}
+
 -keep class com.android.launcher3.BaseRecyclerViewFastScrollBar {
   public void setThumbWidth(int);
   public int getThumbWidth();
diff --git a/res/drawable-hdpi/ic_all_apps_bg_hand.png b/res/drawable-hdpi/ic_all_apps_bg_hand.png
new file mode 100644
index 0000000..64f50df
--- /dev/null
+++ b/res/drawable-hdpi/ic_all_apps_bg_hand.png
Binary files differ
diff --git a/res/drawable-hdpi/ic_all_apps_bg_icon_1.png b/res/drawable-hdpi/ic_all_apps_bg_icon_1.png
new file mode 100644
index 0000000..df3e2de
--- /dev/null
+++ b/res/drawable-hdpi/ic_all_apps_bg_icon_1.png
Binary files differ
diff --git a/res/drawable-hdpi/ic_all_apps_bg_icon_2.png b/res/drawable-hdpi/ic_all_apps_bg_icon_2.png
new file mode 100644
index 0000000..7138ee8
--- /dev/null
+++ b/res/drawable-hdpi/ic_all_apps_bg_icon_2.png
Binary files differ
diff --git a/res/drawable-hdpi/ic_all_apps_bg_icon_3.png b/res/drawable-hdpi/ic_all_apps_bg_icon_3.png
new file mode 100644
index 0000000..ed88199
--- /dev/null
+++ b/res/drawable-hdpi/ic_all_apps_bg_icon_3.png
Binary files differ
diff --git a/res/drawable-hdpi/ic_all_apps_bg_icon_4.png b/res/drawable-hdpi/ic_all_apps_bg_icon_4.png
new file mode 100644
index 0000000..0ff9453
--- /dev/null
+++ b/res/drawable-hdpi/ic_all_apps_bg_icon_4.png
Binary files differ
diff --git a/res/drawable-mdpi/ic_all_apps_bg_hand.png b/res/drawable-mdpi/ic_all_apps_bg_hand.png
new file mode 100644
index 0000000..d94bb7a
--- /dev/null
+++ b/res/drawable-mdpi/ic_all_apps_bg_hand.png
Binary files differ
diff --git a/res/drawable-mdpi/ic_all_apps_bg_icon_1.png b/res/drawable-mdpi/ic_all_apps_bg_icon_1.png
new file mode 100644
index 0000000..76d973f
--- /dev/null
+++ b/res/drawable-mdpi/ic_all_apps_bg_icon_1.png
Binary files differ
diff --git a/res/drawable-mdpi/ic_all_apps_bg_icon_2.png b/res/drawable-mdpi/ic_all_apps_bg_icon_2.png
new file mode 100644
index 0000000..0257f8c
--- /dev/null
+++ b/res/drawable-mdpi/ic_all_apps_bg_icon_2.png
Binary files differ
diff --git a/res/drawable-mdpi/ic_all_apps_bg_icon_3.png b/res/drawable-mdpi/ic_all_apps_bg_icon_3.png
new file mode 100644
index 0000000..67545f5
--- /dev/null
+++ b/res/drawable-mdpi/ic_all_apps_bg_icon_3.png
Binary files differ
diff --git a/res/drawable-mdpi/ic_all_apps_bg_icon_4.png b/res/drawable-mdpi/ic_all_apps_bg_icon_4.png
new file mode 100644
index 0000000..3e36e27b
--- /dev/null
+++ b/res/drawable-mdpi/ic_all_apps_bg_icon_4.png
Binary files differ
diff --git a/res/drawable-xhdpi/ic_all_apps_bg_hand.png b/res/drawable-xhdpi/ic_all_apps_bg_hand.png
new file mode 100644
index 0000000..5dde7f3
--- /dev/null
+++ b/res/drawable-xhdpi/ic_all_apps_bg_hand.png
Binary files differ
diff --git a/res/drawable-xhdpi/ic_all_apps_bg_icon_1.png b/res/drawable-xhdpi/ic_all_apps_bg_icon_1.png
new file mode 100644
index 0000000..f5bd32a
--- /dev/null
+++ b/res/drawable-xhdpi/ic_all_apps_bg_icon_1.png
Binary files differ
diff --git a/res/drawable-xhdpi/ic_all_apps_bg_icon_2.png b/res/drawable-xhdpi/ic_all_apps_bg_icon_2.png
new file mode 100644
index 0000000..fb07956
--- /dev/null
+++ b/res/drawable-xhdpi/ic_all_apps_bg_icon_2.png
Binary files differ
diff --git a/res/drawable-xhdpi/ic_all_apps_bg_icon_3.png b/res/drawable-xhdpi/ic_all_apps_bg_icon_3.png
new file mode 100644
index 0000000..c7d687e
--- /dev/null
+++ b/res/drawable-xhdpi/ic_all_apps_bg_icon_3.png
Binary files differ
diff --git a/res/drawable-xhdpi/ic_all_apps_bg_icon_4.png b/res/drawable-xhdpi/ic_all_apps_bg_icon_4.png
new file mode 100644
index 0000000..e22b962
--- /dev/null
+++ b/res/drawable-xhdpi/ic_all_apps_bg_icon_4.png
Binary files differ
diff --git a/res/drawable-xxhdpi/ic_all_apps_bg_hand.png b/res/drawable-xxhdpi/ic_all_apps_bg_hand.png
new file mode 100644
index 0000000..e107c2e
--- /dev/null
+++ b/res/drawable-xxhdpi/ic_all_apps_bg_hand.png
Binary files differ
diff --git a/res/drawable-xxhdpi/ic_all_apps_bg_icon_1.png b/res/drawable-xxhdpi/ic_all_apps_bg_icon_1.png
new file mode 100644
index 0000000..7482830
--- /dev/null
+++ b/res/drawable-xxhdpi/ic_all_apps_bg_icon_1.png
Binary files differ
diff --git a/res/drawable-xxhdpi/ic_all_apps_bg_icon_2.png b/res/drawable-xxhdpi/ic_all_apps_bg_icon_2.png
new file mode 100644
index 0000000..028c7f4
--- /dev/null
+++ b/res/drawable-xxhdpi/ic_all_apps_bg_icon_2.png
Binary files differ
diff --git a/res/drawable-xxhdpi/ic_all_apps_bg_icon_3.png b/res/drawable-xxhdpi/ic_all_apps_bg_icon_3.png
new file mode 100644
index 0000000..dce7b67
--- /dev/null
+++ b/res/drawable-xxhdpi/ic_all_apps_bg_icon_3.png
Binary files differ
diff --git a/res/drawable-xxhdpi/ic_all_apps_bg_icon_4.png b/res/drawable-xxhdpi/ic_all_apps_bg_icon_4.png
new file mode 100644
index 0000000..811a6b3
--- /dev/null
+++ b/res/drawable-xxhdpi/ic_all_apps_bg_icon_4.png
Binary files differ
diff --git a/res/drawable-xxxhdpi/ic_all_apps_bg_hand.png b/res/drawable-xxxhdpi/ic_all_apps_bg_hand.png
new file mode 100644
index 0000000..c638456
--- /dev/null
+++ b/res/drawable-xxxhdpi/ic_all_apps_bg_hand.png
Binary files differ
diff --git a/res/drawable-xxxhdpi/ic_all_apps_bg_icon_1.png b/res/drawable-xxxhdpi/ic_all_apps_bg_icon_1.png
new file mode 100644
index 0000000..511a02a
--- /dev/null
+++ b/res/drawable-xxxhdpi/ic_all_apps_bg_icon_1.png
Binary files differ
diff --git a/res/drawable-xxxhdpi/ic_all_apps_bg_icon_2.png b/res/drawable-xxxhdpi/ic_all_apps_bg_icon_2.png
new file mode 100644
index 0000000..2cc18f8
--- /dev/null
+++ b/res/drawable-xxxhdpi/ic_all_apps_bg_icon_2.png
Binary files differ
diff --git a/res/drawable-xxxhdpi/ic_all_apps_bg_icon_3.png b/res/drawable-xxxhdpi/ic_all_apps_bg_icon_3.png
new file mode 100644
index 0000000..c32f8ff
--- /dev/null
+++ b/res/drawable-xxxhdpi/ic_all_apps_bg_icon_3.png
Binary files differ
diff --git a/res/drawable-xxxhdpi/ic_all_apps_bg_icon_4.png b/res/drawable-xxxhdpi/ic_all_apps_bg_icon_4.png
new file mode 100644
index 0000000..7bead8a
--- /dev/null
+++ b/res/drawable-xxxhdpi/ic_all_apps_bg_icon_4.png
Binary files differ
diff --git a/res/layout/all_apps_empty_search.xml b/res/layout/all_apps_empty_search.xml
index b9b493e..5439111 100644
--- a/res/layout/all_apps_empty_search.xml
+++ b/res/layout/all_apps_empty_search.xml
@@ -19,7 +19,7 @@
     android:layout_width="wrap_content"
     android:layout_height="wrap_content"
     android:gravity="start"
-    android:paddingTop="20dp"
+    android:paddingTop="@dimen/all_apps_empty_search_message_top_offset"
     android:paddingBottom="8dp"
     android:paddingLeft="16dp"
     android:paddingRight="16dp"
diff --git a/res/values-sw600dp/dimens.xml b/res/values-sw600dp/dimens.xml
index 2651fbb..fb54f12 100644
--- a/res/values-sw600dp/dimens.xml
+++ b/res/values-sw600dp/dimens.xml
@@ -19,6 +19,8 @@
     <dimen name="all_apps_grid_view_start_margin">0dp</dimen>
     <dimen name="all_apps_grid_section_text_size">26sp</dimen>
     <dimen name="all_apps_icon_top_bottom_padding">12dp</dimen>
+    <dimen name="all_apps_background_canvas_width">850dp</dimen>
+    <dimen name="all_apps_background_canvas_height">525dp</dimen>
 
 <!-- Cling -->
     <dimen name="cling_migration_logo_height">400dp</dimen>
diff --git a/res/values-sw720dp/dimens.xml b/res/values-sw720dp/dimens.xml
index d48f9ee..807fab9 100644
--- a/res/values-sw720dp/dimens.xml
+++ b/res/values-sw720dp/dimens.xml
@@ -18,6 +18,8 @@
 <!-- All Apps -->
     <dimen name="all_apps_search_bar_height">54dp</dimen>
     <dimen name="all_apps_icon_top_bottom_padding">14dp</dimen>
+    <dimen name="all_apps_empty_search_message_top_offset">64dp</dimen>
+    <dimen name="all_apps_empty_search_bg_top_offset">180dp</dimen>
 
 <!-- QSB -->
     <dimen name="toolbar_button_vertical_padding">8dip</dimen>
diff --git a/res/values/dimens.xml b/res/values/dimens.xml
index 3f14151..3672179 100644
--- a/res/values/dimens.xml
+++ b/res/values/dimens.xml
@@ -74,6 +74,10 @@
     <dimen name="all_apps_prediction_icon_top_padding">8dp</dimen>
     <dimen name="all_apps_prediction_icon_bottom_padding">18dp</dimen>
     <dimen name="all_apps_list_top_bottom_padding">8dp</dimen>
+    <dimen name="all_apps_empty_search_message_top_offset">40dp</dimen>
+    <dimen name="all_apps_empty_search_bg_top_offset">144dp</dimen>
+    <dimen name="all_apps_background_canvas_width">700dp</dimen>
+    <dimen name="all_apps_background_canvas_height">475dp</dimen>
 
 <!-- Widget tray -->
     <dimen name="widget_container_inset">8dp</dimen>
diff --git a/src/com/android/launcher3/allapps/AllAppsBackgroundDrawable.java b/src/com/android/launcher3/allapps/AllAppsBackgroundDrawable.java
new file mode 100644
index 0000000..117aca9
--- /dev/null
+++ b/src/com/android/launcher3/allapps/AllAppsBackgroundDrawable.java
@@ -0,0 +1,194 @@
+/*
+ * Copyright (C) 2015 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.allapps;
+
+import android.animation.ObjectAnimator;
+import android.content.Context;
+import android.content.res.Resources;
+import android.graphics.Canvas;
+import android.graphics.ColorFilter;
+import android.graphics.PixelFormat;
+import android.graphics.Rect;
+import android.graphics.drawable.Drawable;
+
+import android.view.Gravity;
+import com.android.launcher3.R;
+
+/**
+ * A helper class to positon and orient a drawable to be drawn.
+ */
+class TransformedImageDrawable {
+    private Drawable mImage;
+    private float mXPercent;
+    private float mYPercent;
+    private int mGravity;
+
+    /**
+     * @param gravity If one of the Gravity center values, the x and y offset will take the width
+     *                and height of the image into account to center the image to the offset.
+     */
+    public TransformedImageDrawable(Resources res, int resourceId, float xPct, float yPct,
+            int gravity) {
+        mImage = res.getDrawable(resourceId);
+        mXPercent = xPct;
+        mYPercent = yPct;
+        mGravity = gravity;
+    }
+
+    public void setAlpha(int alpha) {
+        mImage.setAlpha(alpha);
+    }
+
+    public int getAlpha() {
+        return mImage.getAlpha();
+    }
+
+    public void updateBounds(Rect bounds) {
+        int width = mImage.getIntrinsicWidth();
+        int height = mImage.getIntrinsicHeight();
+        int left = bounds.left + (int) (mXPercent * bounds.width());
+        int top = bounds.top + (int) (mYPercent * bounds.height());
+        if ((mGravity & Gravity.CENTER_HORIZONTAL) == Gravity.CENTER_HORIZONTAL) {
+            left -= (width / 2);
+        }
+        if ((mGravity & Gravity.CENTER_VERTICAL) == Gravity.CENTER_VERTICAL) {
+            top -= (height / 2);
+        }
+        mImage.setBounds(left, top, left + width, top + height);
+    }
+
+    public void draw(Canvas canvas) {
+        int c = canvas.save(Canvas.MATRIX_SAVE_FLAG);
+        mImage.draw(canvas);
+        canvas.restoreToCount(c);
+    }
+}
+
+/**
+ * This is a custom composite drawable that has a fixed virtual size and dynamically lays out its
+ * children images relatively within its bounds.  This way, we can reduce the memory usage of a
+ * single, large sparsely populated image.
+ */
+public class AllAppsBackgroundDrawable extends Drawable {
+
+    private final TransformedImageDrawable mHand;
+    private final TransformedImageDrawable[] mIcons;
+    private final int mWidth;
+    private final int mHeight;
+
+    private ObjectAnimator mBackgroundAnim;
+
+    public AllAppsBackgroundDrawable(Context context) {
+        Resources res = context.getResources();
+        mHand = new TransformedImageDrawable(res, R.drawable.ic_all_apps_bg_hand,
+                0.575f, 0.1f, Gravity.CENTER_HORIZONTAL);
+        mIcons = new TransformedImageDrawable[4];
+        mIcons[0] = new TransformedImageDrawable(res, R.drawable.ic_all_apps_bg_icon_1,
+                0.375f, 0, Gravity.CENTER_HORIZONTAL);
+        mIcons[1] = new TransformedImageDrawable(res, R.drawable.ic_all_apps_bg_icon_2,
+                0.3125f, 0.25f, Gravity.CENTER_HORIZONTAL);
+        mIcons[2] = new TransformedImageDrawable(res, R.drawable.ic_all_apps_bg_icon_3,
+                0.475f, 0.4f, Gravity.CENTER_HORIZONTAL);
+        mIcons[3] = new TransformedImageDrawable(res, R.drawable.ic_all_apps_bg_icon_4,
+                0.7f, 0.125f, Gravity.CENTER_HORIZONTAL);
+        mWidth = res.getDimensionPixelSize(R.dimen.all_apps_background_canvas_width);
+        mHeight = res.getDimensionPixelSize(R.dimen.all_apps_background_canvas_height);
+    }
+
+    /**
+     * Animates the background alpha.
+     */
+    public void animateBgAlpha(float finalAlpha, int duration) {
+        int finalAlphaI = (int) (finalAlpha * 255f);
+        if (getAlpha() != finalAlphaI) {
+            mBackgroundAnim = cancelAnimator(mBackgroundAnim);
+            mBackgroundAnim = ObjectAnimator.ofInt(this, "alpha", finalAlphaI);
+            mBackgroundAnim.setDuration(duration);
+            mBackgroundAnim.start();
+        }
+    }
+
+    /**
+     * Sets the background alpha immediately.
+     */
+    public void setBgAlpha(float finalAlpha) {
+        int finalAlphaI = (int) (finalAlpha * 255f);
+        if (getAlpha() != finalAlphaI) {
+            mBackgroundAnim = cancelAnimator(mBackgroundAnim);
+            setAlpha(finalAlphaI);
+        }
+    }
+
+    @Override
+    public int getIntrinsicWidth() {
+        return mWidth;
+    }
+
+    @Override
+    public int getIntrinsicHeight() {
+        return mHeight;
+    }
+
+    @Override
+    public void draw(Canvas canvas) {
+        mHand.draw(canvas);
+        for (int i = 0; i < mIcons.length; i++) {
+            mIcons[i].draw(canvas);
+        }
+    }
+
+    @Override
+    protected void onBoundsChange(Rect bounds) {
+        super.onBoundsChange(bounds);
+        mHand.updateBounds(bounds);
+        for (int i = 0; i < mIcons.length; i++) {
+            mIcons[i].updateBounds(bounds);
+        }
+        invalidateSelf();
+    }
+
+    @Override
+    public void setAlpha(int alpha) {
+        mHand.setAlpha(alpha);
+        for (int i = 0; i < mIcons.length; i++) {
+            mIcons[i].setAlpha(alpha);
+        }
+        invalidateSelf();
+    }
+
+    @Override
+    public int getAlpha() {
+        return mHand.getAlpha();
+    }
+
+    @Override
+    public void setColorFilter(ColorFilter colorFilter) {
+        // Do nothing
+    }
+
+    @Override
+    public int getOpacity() {
+        return PixelFormat.TRANSLUCENT;
+    }
+
+    private ObjectAnimator cancelAnimator(ObjectAnimator animator) {
+        if (animator != null) {
+            animator.removeAllListeners();
+            animator.cancel();
+        }
+        return null;
+    }
+}
diff --git a/src/com/android/launcher3/allapps/AllAppsContainerView.java b/src/com/android/launcher3/allapps/AllAppsContainerView.java
index 6d008ab..88c6aca 100644
--- a/src/com/android/launcher3/allapps/AllAppsContainerView.java
+++ b/src/com/android/launcher3/allapps/AllAppsContainerView.java
@@ -615,13 +615,14 @@
         if (apps != null) {
             mApps.setOrderedFilter(apps);
             mAdapter.setLastSearchQuery(query);
-            mAppsRecyclerView.scrollToTop();
+            mAppsRecyclerView.onSearchResultsChanged();
         }
     }
 
     @Override
     public void clearSearchResult() {
         mApps.setOrderedFilter(null);
+        mAppsRecyclerView.onSearchResultsChanged();
 
         // Clear the search query
         mSearchQueryBuilder.clear();
diff --git a/src/com/android/launcher3/allapps/AllAppsGridAdapter.java b/src/com/android/launcher3/allapps/AllAppsGridAdapter.java
index f7c4489..1f95133 100644
--- a/src/com/android/launcher3/allapps/AllAppsGridAdapter.java
+++ b/src/com/android/launcher3/allapps/AllAppsGridAdapter.java
@@ -24,11 +24,13 @@
 import android.graphics.Paint;
 import android.graphics.PointF;
 import android.graphics.Rect;
+import android.graphics.drawable.Drawable;
 import android.support.v4.view.accessibility.AccessibilityRecordCompat;
 import android.support.v4.view.accessibility.AccessibilityEventCompat;
 import android.net.Uri;
 import android.support.v7.widget.GridLayoutManager;
 import android.support.v7.widget.RecyclerView;
+import android.view.Gravity;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewConfiguration;
@@ -511,14 +513,17 @@
             case EMPTY_SEARCH_VIEW_TYPE:
                 TextView emptyViewText = (TextView) holder.mContent;
                 emptyViewText.setText(mEmptySearchMessage);
+                emptyViewText.setGravity(mApps.hasNoFilteredResults() ? Gravity.CENTER :
+                        Gravity.START | Gravity.CENTER_VERTICAL);
                 break;
             case SEARCH_MARKET_VIEW_TYPE:
-                View searchView = holder.mContent;
+                TextView searchView = (TextView) holder.mContent;
                 if (mMarketSearchIntent != null) {
                     searchView.setVisibility(View.VISIBLE);
                     searchView.setContentDescription(mMarketSearchMessage);
-                    ((TextView) searchView.findViewById(R.id.search_market_text))
-                            .setText(mMarketSearchMessage);
+                    searchView.setGravity(mApps.hasNoFilteredResults() ? Gravity.CENTER :
+                            Gravity.START | Gravity.CENTER_VERTICAL);
+                    searchView.setText(mMarketSearchMessage);
                 } else {
                     searchView.setVisibility(View.GONE);
                 }
diff --git a/src/com/android/launcher3/allapps/AllAppsRecyclerView.java b/src/com/android/launcher3/allapps/AllAppsRecyclerView.java
index 1cde7bf..e33b4db 100644
--- a/src/com/android/launcher3/allapps/AllAppsRecyclerView.java
+++ b/src/com/android/launcher3/allapps/AllAppsRecyclerView.java
@@ -15,8 +15,11 @@
  */
 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.drawable.Drawable;
 import android.os.Bundle;
 import android.support.v7.widget.LinearLayoutManager;
 import android.support.v7.widget.RecyclerView;
@@ -26,6 +29,7 @@
 import com.android.launcher3.BaseRecyclerView;
 import com.android.launcher3.BaseRecyclerViewFastScrollBar;
 import com.android.launcher3.DeviceProfile;
+import com.android.launcher3.R;
 import com.android.launcher3.Stats;
 import com.android.launcher3.Utilities;
 import com.android.launcher3.util.Thunk;
@@ -57,6 +61,9 @@
 
     private ScrollPositionState mScrollPosState = new ScrollPositionState();
 
+    private AllAppsBackgroundDrawable mEmptySearchBackground;
+    private int mEmptySearchBackgroundTopOffset;
+
     public AllAppsRecyclerView(Context context) {
         this(context, null);
     }
@@ -72,7 +79,11 @@
     public AllAppsRecyclerView(Context context, AttributeSet attrs, int defStyleAttr,
             int defStyleRes) {
         super(context, attrs, defStyleAttr);
+
+        Resources res = getResources();
         mScrollbar.setDetachThumbOnFastScroll();
+        mEmptySearchBackgroundTopOffset = res.getDimensionPixelSize(
+                R.dimen.all_apps_empty_search_bg_top_offset);
     }
 
     /**
@@ -118,6 +129,30 @@
     }
 
     @Override
+    public void onDraw(Canvas c) {
+        // Draw the background
+        if (mEmptySearchBackground != null && mEmptySearchBackground.getAlpha() > 0) {
+            c.clipRect(mBackgroundPadding.left, mBackgroundPadding.top,
+                    getWidth() - mBackgroundPadding.right,
+                    getHeight() - mBackgroundPadding.bottom);
+
+            mEmptySearchBackground.draw(c);
+        }
+
+        super.onDraw(c);
+    }
+
+    @Override
+    protected boolean verifyDrawable(Drawable who) {
+        return who == mEmptySearchBackground || super.verifyDrawable(who);
+    }
+
+    @Override
+    protected void onSizeChanged(int w, int h, int oldw, int oldh) {
+        updateEmptySearchBackgroundBounds();
+    }
+
+    @Override
     protected void onFinishInflate() {
         super.onFinishInflate();
 
@@ -137,6 +172,25 @@
         }
     }
 
+    public void onSearchResultsChanged() {
+        // Always scroll the view to the top so the user can see the changed results
+        scrollToTop();
+
+        if (mApps.hasNoFilteredResults()) {
+            if (mEmptySearchBackground == null) {
+                mEmptySearchBackground = new AllAppsBackgroundDrawable(getContext());
+                mEmptySearchBackground.setAlpha(0);
+                mEmptySearchBackground.setCallback(this);
+                updateEmptySearchBackgroundBounds();
+            }
+            mEmptySearchBackground.animateBgAlpha(1f, 150);
+        } else if (mEmptySearchBackground != null) {
+            // For the time being, we just immediately hide the background to ensure that it does
+            // not overlap with the results
+            mEmptySearchBackground.setBgAlpha(0f);
+        }
+    }
+
     /**
      * Maps the touch (from 0..1) to the adapter position that should be visible.
      */
@@ -386,4 +440,20 @@
             return 0;
         }
     }
+
+    /**
+     * Updates the bounds of the empty search background.
+     */
+    private void updateEmptySearchBackgroundBounds() {
+        if (mEmptySearchBackground == null) {
+            return;
+        }
+
+        // Center the empty search background on this new view bounds
+        int x = (getMeasuredWidth() - mEmptySearchBackground.getIntrinsicWidth()) / 2;
+        int y = mEmptySearchBackgroundTopOffset;
+        mEmptySearchBackground.setBounds(x, y,
+                x + mEmptySearchBackground.getIntrinsicWidth(),
+                y + mEmptySearchBackground.getIntrinsicHeight());
+    }
 }