Merging search bar with all apps

Change-Id: I78577124cd3c05d52669c3e52b0294d6eb1d194d

5 files changed, 302 insertions, 377 deletions

diff --git a/src/com/android/launcher3/allapps/AllAppsContainerView.java b/src/com/android/launcher3/allapps/AllAppsContainerView.java
index f9bb13450..8f8858fb6 100644
--- a/src/com/android/launcher3/allapps/AllAppsContainerView.java
+++ b/src/com/android/launcher3/allapps/AllAppsContainerView.java
@@ -17,11 +17,9 @@ package com.android.launcher3.allapps;
 
 import android.annotation.SuppressLint;
 import android.content.Context;
-import android.content.Intent;
 import android.content.res.Resources;
 import android.graphics.Point;
 import android.graphics.Rect;
-import android.graphics.drawable.InsetDrawable;
 import android.support.v7.widget.RecyclerView;
 import android.text.Selection;
 import android.text.SpannableStringBuilder;
@@ -32,8 +30,7 @@ import android.view.LayoutInflater;
 import android.view.MotionEvent;
 import android.view.View;
 import android.view.ViewConfiguration;
-import android.view.ViewGroup;
-import android.widget.LinearLayout;
+
 import com.android.launcher3.AppInfo;
 import com.android.launcher3.BaseContainerView;
 import com.android.launcher3.BubbleTextView;
@@ -42,6 +39,7 @@ import com.android.launcher3.DeleteDropTarget;
 import com.android.launcher3.DeviceProfile;
 import com.android.launcher3.DragSource;
 import com.android.launcher3.DropTarget;
+import com.android.launcher3.ExtendedEditText;
 import com.android.launcher3.Folder;
 import com.android.launcher3.ItemInfo;
 import com.android.launcher3.Launcher;
@@ -50,7 +48,6 @@ import com.android.launcher3.R;
 import com.android.launcher3.Utilities;
 import com.android.launcher3.Workspace;
 import com.android.launcher3.util.ComponentKey;
-import com.android.launcher3.util.Thunk;
 
 import java.nio.charset.Charset;
 import java.nio.charset.CharsetEncoder;
@@ -135,19 +132,19 @@ public class AllAppsContainerView extends BaseContainerView implements DragSourc
     private static final int MIN_ROWS_IN_MERGED_SECTION_PHONE = 3;
     private static final int MAX_NUM_MERGES_PHONE = 2;
 
-    @Thunk Launcher mLauncher;
-    @Thunk AlphabeticalAppsList mApps;
-    private AllAppsGridAdapter mAdapter;
-    private RecyclerView.LayoutManager mLayoutManager;
-    private RecyclerView.ItemDecoration mItemDecoration;
-
-    @Thunk View mContent;
-    @Thunk View mContainerView;
-    @Thunk View mRevealView;
-    @Thunk AllAppsRecyclerView mAppsRecyclerView;
-    @Thunk AllAppsSearchBarController mSearchBarController;
-    private ViewGroup mSearchBarContainerView;
-    private View mSearchBarView;
+    private final Launcher mLauncher;
+    private final AlphabeticalAppsList mApps;
+    private final AllAppsGridAdapter mAdapter;
+    private final RecyclerView.LayoutManager mLayoutManager;
+    private final RecyclerView.ItemDecoration mItemDecoration;
+
+    private AllAppsRecyclerView mAppsRecyclerView;
+    private AllAppsSearchBarController mSearchBarController;
+
+    private View mSearchContainer;
+    private ExtendedEditText mSearchInput;
+    private HeaderElevationController mElevationController;
+
     private SpannableStringBuilder mSearchQueryBuilder = null;
 
     private int mSectionNamesMargin;
@@ -159,14 +156,6 @@ public class AllAppsContainerView extends BaseContainerView implements DragSourc
     // This coordinate is relative to its parent
     private final Point mIconLastTouchPos = new Point();
 
-    private View.OnClickListener mSearchClickListener = new View.OnClickListener() {
-        @Override
-        public void onClick(View v) {
-            Intent searchIntent = (Intent) v.getTag();
-            mLauncher.startActivitySafely(v, searchIntent, null);
-        }
-    };
-
     public AllAppsContainerView(Context context) {
         this(context, null);
     }
@@ -236,14 +225,7 @@ public class AllAppsContainerView extends BaseContainerView implements DragSourc
             throw new RuntimeException("Expected search bar controller to only be set once");
         }
         mSearchBarController = searchController;
-        mSearchBarController.initialize(mApps, this);
-
-        // Add the new search view to the layout
-        View searchBarView = searchController.getView(mSearchBarContainerView);
-        mSearchBarContainerView.addView(searchBarView);
-        mSearchBarContainerView.setVisibility(View.VISIBLE);
-        mSearchBarView = searchBarView;
-        setHasSearchBar();
+        mSearchBarController.initialize(mApps, mSearchInput, mAppsRecyclerView, this);
 
         updateBackgroundAndPaddings();
     }
@@ -256,34 +238,6 @@ public class AllAppsContainerView extends BaseContainerView implements DragSourc
     }
 
     /**
-     * Returns the content view used for the launcher transitions.
-     */
-    public View getContentView() {
-        return mContainerView;
-    }
-
-    /**
-     * Returns the all apps search view.
-     */
-    public View getSearchBarView() {
-        return mSearchBarView;
-    }
-
-    /**
-     * Returns the reveal view used for the launcher transitions.
-     */
-    public View getRevealView() {
-        return mRevealView;
-    }
-
-    /**
-     * Returns an new instance of the default app search controller.
-     */
-    public AllAppsSearchBarController newDefaultAppSearchController() {
-        return new DefaultAppSearchController(getContext(), this, mAppsRecyclerView);
-    }
-
-    /**
      * Focuses the search field and begins an app search.
      */
     public void startAppsSearch() {
@@ -304,25 +258,24 @@ public class AllAppsContainerView extends BaseContainerView implements DragSourc
     @Override
     protected void onFinishInflate() {
         super.onFinishInflate();
-        boolean isRtl = Utilities.isRtl(getResources());
-        mAdapter.setRtl(isRtl);
-        mContent = findViewById(R.id.content);
+        mAdapter.setRtl(Utilities.isRtl(getResources()));
 
         // This is a focus listener that proxies focus from a view into the list view.  This is to
         // work around the search box from getting first focus and showing the cursor.
-        View.OnFocusChangeListener focusProxyListener = new View.OnFocusChangeListener() {
+        getContentView().setOnFocusChangeListener(new View.OnFocusChangeListener() {
             @Override
             public void onFocusChange(View v, boolean hasFocus) {
                 if (hasFocus) {
                     mAppsRecyclerView.requestFocus();
                 }
             }
-        };
-        mSearchBarContainerView = (ViewGroup) findViewById(R.id.search_box_container);
-        mSearchBarContainerView.setOnFocusChangeListener(focusProxyListener);
-        mContainerView = findViewById(R.id.all_apps_container);
-        mContainerView.setOnFocusChangeListener(focusProxyListener);
-        mRevealView = findViewById(R.id.all_apps_reveal);
+        });
+
+        mSearchContainer = findViewById(R.id.search_container);
+        mSearchInput = (ExtendedEditText) findViewById(R.id.search_box_input);
+        mElevationController = Utilities.ATLEAST_LOLLIPOP
+                ? new HeaderElevationController.ControllerVL(mSearchContainer)
+                : new HeaderElevationController.ControllerV16(mSearchContainer);
 
         // Load the all apps recycler view
         mAppsRecyclerView = (AllAppsRecyclerView) findViewById(R.id.apps_list_view);
@@ -330,22 +283,28 @@ public class AllAppsContainerView extends BaseContainerView implements DragSourc
         mAppsRecyclerView.setLayoutManager(mLayoutManager);
         mAppsRecyclerView.setAdapter(mAdapter);
         mAppsRecyclerView.setHasFixedSize(true);
+        mAppsRecyclerView.addOnScrollListener(mElevationController);
+        mAppsRecyclerView.setElevationController(mElevationController);
+
         if (mItemDecoration != null) {
             mAppsRecyclerView.addItemDecoration(mItemDecoration);
         }
 
         // Precalculate the prediction icon and normal icon sizes
         LayoutInflater layoutInflater = LayoutInflater.from(getContext());
+        final int widthMeasureSpec = MeasureSpec.makeMeasureSpec(
+                getResources().getDisplayMetrics().widthPixels, MeasureSpec.AT_MOST);
+        final int heightMeasureSpec = MeasureSpec.makeMeasureSpec(
+                getResources().getDisplayMetrics().heightPixels, MeasureSpec.AT_MOST);
+
         BubbleTextView icon = (BubbleTextView) layoutInflater.inflate(
                 R.layout.all_apps_icon, this, false);
         icon.applyDummyInfo();
-        icon.measure(MeasureSpec.makeMeasureSpec(Integer.MAX_VALUE, MeasureSpec.AT_MOST),
-                MeasureSpec.makeMeasureSpec(Integer.MAX_VALUE, MeasureSpec.AT_MOST));
+        icon.measure(widthMeasureSpec, heightMeasureSpec);
         BubbleTextView predIcon = (BubbleTextView) layoutInflater.inflate(
                 R.layout.all_apps_prediction_bar_icon, this, false);
         predIcon.applyDummyInfo();
-        predIcon.measure(MeasureSpec.makeMeasureSpec(Integer.MAX_VALUE, MeasureSpec.AT_MOST),
-                MeasureSpec.makeMeasureSpec(Integer.MAX_VALUE, MeasureSpec.AT_MOST));
+        predIcon.measure(widthMeasureSpec, heightMeasureSpec);
         mAppsRecyclerView.setPremeasuredIconHeights(predIcon.getMeasuredHeight(),
                 icon.getMeasuredHeight());
 
@@ -360,8 +319,11 @@ public class AllAppsContainerView extends BaseContainerView implements DragSourc
     @Override
     protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
         // Update the number of items in the grid before we measure the view
-        int availableWidth = !mContentBounds.isEmpty() ? mContentBounds.width() :
-                MeasureSpec.getSize(widthMeasureSpec);
+        // TODO: mSectionNamesMargin is currently 0, but also account for it,
+        // if it's enabled in the future.
+        int availableWidth = (!mContentBounds.isEmpty() ? mContentBounds.width() :
+                MeasureSpec.getSize(widthMeasureSpec))
+                    - 2 * mAppsRecyclerView.getMaxScrollbarWidth();
         DeviceProfile grid = mLauncher.getDeviceProfile();
         grid.updateAppsViewNumCols(getResources(), availableWidth);
         if (mNumAppsPerRow != grid.allAppsNumCols ||
@@ -380,6 +342,12 @@ public class AllAppsContainerView extends BaseContainerView implements DragSourc
             mAppsRecyclerView.setNumAppsPerRow(grid, mNumAppsPerRow);
             mAdapter.setNumAppsPerRow(mNumAppsPerRow);
             mApps.setNumAppsPerRow(mNumAppsPerRow, mNumPredictedAppsPerRow, mergeAlgorithm);
+
+            if (mNumAppsPerRow > 0) {
+                int iconSize = availableWidth / mNumAppsPerRow;
+                int iconSpacing = (iconSize - grid.allAppsIconSizePx) / 2;
+                mSearchInput.setPaddingRelative(iconSpacing, 0, iconSpacing, 0);
+            }
         }
 
         super.onMeasure(widthMeasureSpec, heightMeasureSpec);
@@ -391,51 +359,33 @@ public class AllAppsContainerView extends BaseContainerView implements DragSourc
      * recycler view to handle touch events (for fast scrolling) all the way to the edge.
      */
     @Override
-    protected void onUpdateBackgroundAndPaddings(Rect searchBarBounds, Rect padding) {
-        boolean isRtl = Utilities.isRtl(getResources());
-
-        // TODO: Use quantum_panel instead of quantum_panel_shape
-        InsetDrawable background = new InsetDrawable(
-                getResources().getDrawable(R.drawable.quantum_panel_shape), padding.left, 0,
-                padding.right, 0);
-        Rect bgPadding = new Rect();
-        background.getPadding(bgPadding);
-        mContainerView.setBackground(background);
-        mRevealView.setBackground(background.getConstantState().newDrawable());
+    protected void onUpdateBgPadding(Rect padding, Rect bgPadding) {
         mAppsRecyclerView.updateBackgroundPadding(bgPadding);
         mAdapter.updateBackgroundPadding(bgPadding);
+        mElevationController.updateBackgroundPadding(bgPadding);
 
         // Hack: We are going to let the recycler view take the full width, so reset the padding on
         // the container to zero after setting the background and apply the top-bottom padding to
         // the content view instead so that the launcher transition clips correctly.
-        mContent.setPadding(0, padding.top, 0, padding.bottom);
-        mContainerView.setPadding(0, 0, 0, 0);
+        getContentView().setPadding(0, 0, 0, 0);
 
         // Pad the recycler view by the background padding plus the start margin (for the section
         // names)
-        int startInset = Math.max(mSectionNamesMargin, mAppsRecyclerView.getMaxScrollbarWidth());
+        int maxScrollBarWidth = mAppsRecyclerView.getMaxScrollbarWidth();
+        int startInset = Math.max(mSectionNamesMargin, maxScrollBarWidth);
         int topBottomPadding = mRecyclerViewTopBottomPadding;
-        if (isRtl) {
-            mAppsRecyclerView.setPadding(padding.left + mAppsRecyclerView.getMaxScrollbarWidth(),
+        if (Utilities.isRtl(getResources())) {
+            mAppsRecyclerView.setPadding(padding.left + maxScrollBarWidth,
                     topBottomPadding, padding.right + startInset, topBottomPadding);
         } else {
             mAppsRecyclerView.setPadding(padding.left + startInset, topBottomPadding,
-                    padding.right + mAppsRecyclerView.getMaxScrollbarWidth(), topBottomPadding);
+                    padding.right + maxScrollBarWidth, topBottomPadding);
         }
 
-        // Inset the search bar to fit its bounds above the container
-        if (mSearchBarView != null) {
-            Rect backgroundPadding = new Rect();
-            if (mSearchBarView.getBackground() != null) {
-                mSearchBarView.getBackground().getPadding(backgroundPadding);
-            }
-            LinearLayout.LayoutParams lp = (LinearLayout.LayoutParams)
-                    mSearchBarContainerView.getLayoutParams();
-            lp.leftMargin = searchBarBounds.left - backgroundPadding.left;
-            lp.topMargin = searchBarBounds.top - backgroundPadding.top;
-            lp.rightMargin = (getMeasuredWidth() - searchBarBounds.right) - backgroundPadding.right;
-            mSearchBarContainerView.requestLayout();
-        }
+        MarginLayoutParams lp = (MarginLayoutParams) mSearchContainer.getLayoutParams();
+        lp.leftMargin = padding.left;
+        lp.rightMargin = padding.right;
+        mSearchContainer.setLayoutParams(lp);
     }
 
     @Override
diff --git a/src/com/android/launcher3/allapps/AllAppsRecyclerView.java b/src/com/android/launcher3/allapps/AllAppsRecyclerView.java
index 1cb03c989..2b3d061e6 100644
--- a/src/com/android/launcher3/allapps/AllAppsRecyclerView.java
+++ b/src/com/android/launcher3/allapps/AllAppsRecyclerView.java
@@ -53,6 +53,8 @@ public class AllAppsRecyclerView extends BaseRecyclerView
     private AllAppsBackgroundDrawable mEmptySearchBackground;
     private int mEmptySearchBackgroundTopOffset;
 
+    private HeaderElevationController mElevationController;
+
     public AllAppsRecyclerView(Context context) {
         this(context, null);
     }
@@ -83,6 +85,10 @@ public class AllAppsRecyclerView extends BaseRecyclerView
         mFastScrollHelper = new AllAppsFastScrollHelper(this, apps);
     }
 
+    public void setElevationController(HeaderElevationController elevationController) {
+        mElevationController = elevationController;
+    }
+
     /**
      * Sets the number of apps per row in this recycler view.
      */
@@ -116,6 +122,9 @@ public class AllAppsRecyclerView extends BaseRecyclerView
             mScrollbar.reattachThumbToScroll();
         }
         scrollToPosition(0);
+        if (mElevationController != null) {
+            mElevationController.reset();
+        }
     }
 
     /**
diff --git a/src/com/android/launcher3/allapps/AllAppsSearchBarController.java b/src/com/android/launcher3/allapps/AllAppsSearchBarController.java
index 2b363c0cb..fdce3895f 100644
--- a/src/com/android/launcher3/allapps/AllAppsSearchBarController.java
+++ b/src/com/android/launcher3/allapps/AllAppsSearchBarController.java
@@ -15,65 +15,179 @@
  */
 package com.android.launcher3.allapps;
 
-import android.content.ComponentName;
+import android.content.Context;
 import android.graphics.Rect;
+import android.text.Editable;
+import android.text.TextWatcher;
+import android.view.KeyEvent;
 import android.view.View;
 import android.view.ViewGroup;
+import android.view.inputmethod.EditorInfo;
+import android.view.inputmethod.InputMethodManager;
+import android.widget.TextView;
+import android.widget.TextView.OnEditorActionListener;
 
+import com.android.launcher3.ExtendedEditText;
+import com.android.launcher3.Utilities;
 import com.android.launcher3.util.ComponentKey;
 
 import java.util.ArrayList;
+import java.util.List;
 
 /**
  * An interface to a search box that AllApps can command.
  */
-public abstract class AllAppsSearchBarController {
+public abstract class AllAppsSearchBarController
+        implements TextWatcher, OnEditorActionListener, ExtendedEditText.OnBackKeyListener {
 
+    private static final boolean ALLOW_SINGLE_APP_LAUNCH = true;
+
+    protected AllAppsRecyclerView mAppsRecyclerView;
     protected AlphabeticalAppsList mApps;
     protected Callbacks mCb;
+    protected ExtendedEditText mInput;
+
+    protected DefaultAppSearchAlgorithm mSearchAlgorithm;
+    protected InputMethodManager mInputMethodManager;
 
     /**
      * Sets the references to the apps model and the search result callback.
      */
-    public final void initialize(AlphabeticalAppsList apps, Callbacks cb) {
+    public final void initialize(
+            AlphabeticalAppsList apps, ExtendedEditText input,
+            AllAppsRecyclerView recycleView, Callbacks cb) {
         mApps = apps;
         mCb = cb;
-        onInitialize();
+        mAppsRecyclerView = recycleView;
+
+        mInput = input;
+        mInput.addTextChangedListener(this);
+        mInput.setOnEditorActionListener(this);
+        mInput.setOnBackKeyListener(this);
+
+        mInputMethodManager = (InputMethodManager)
+                mInput.getContext().getSystemService(Context.INPUT_METHOD_SERVICE);
+
+        mSearchAlgorithm = onInitializeSearch();
     }
 
     /**
-     * To be overridden by subclasses.  This method will get called when the controller is set,
-     * before getView().
+     * To be overridden by subclasses. This method will get called when the controller is set.
      */
-    protected abstract void onInitialize();
+    protected DefaultAppSearchAlgorithm onInitializeSearch() {
+        return null;
+    }
+
+    @Override
+    public void beforeTextChanged(CharSequence s, int start, int count, int after) {
+        // Do nothing
+    }
+
+    @Override
+    public void onTextChanged(CharSequence s, int start, int before, int count) {
+        // Do nothing
+    }
+
+    @Override
+    public void afterTextChanged(final Editable s) {
+        String query = s.toString();
+        if (query.isEmpty()) {
+            mSearchAlgorithm.cancel(true);
+            mCb.clearSearchResult();
+        } else {
+            mSearchAlgorithm.cancel(false);
+            mSearchAlgorithm.doSearch(query, mCb);
+        }
+    }
+
+    @Override
+    public boolean onEditorAction(TextView v, int actionId, KeyEvent event) {
+        // Skip if we disallow app-launch-on-enter
+        if (!ALLOW_SINGLE_APP_LAUNCH) {
+            return false;
+        }
+        // Skip if it's not the right action
+        if (actionId != EditorInfo.IME_ACTION_SEARCH) {
+            return false;
+        }
+        // Skip if there are more than one icon
+        if (mApps.getNumFilteredApps() > 1) {
+            return false;
+        }
+        // Otherwise, find the first icon, or fallback to the search-market-view and launch it
+        List<AlphabeticalAppsList.AdapterItem> items = mApps.getAdapterItems();
+        for (int i = 0; i < items.size(); i++) {
+            AlphabeticalAppsList.AdapterItem item = items.get(i);
+            switch (item.viewType) {
+                case AllAppsGridAdapter.ICON_VIEW_TYPE:
+                case AllAppsGridAdapter.SEARCH_MARKET_VIEW_TYPE:
+                    mAppsRecyclerView.getChildAt(i).performClick();
+                    mInputMethodManager.hideSoftInputFromWindow(mInput.getWindowToken(), 0);
+                    return true;
+            }
+        }
+        return false;
+    }
+
+    @Override
+    public boolean onBackKey() {
+        // Only hide the search field if there is no query, or if there
+        // are no filtered results
+        String query = Utilities.trim(mInput.getEditableText().toString());
+        if (query.isEmpty() || mApps.hasNoFilteredResults()) {
+            reset();
+            return true;
+        }
+        return false;
+    }
+
+    /**
+     * Resets the search bar state.
+     */
+    public void reset() {
+        unfocusSearchField();
+        mCb.clearSearchResult();
+        mInput.setText("");
+        mInputMethodManager.hideSoftInputFromWindow(mInput.getWindowToken(), 0);
+    }
+
+    protected void unfocusSearchField() {
+        View nextFocus = mInput.focusSearch(View.FOCUS_DOWN);
+        if (nextFocus != null) {
+            nextFocus.requestFocus();
+        }
+    }
 
     /**
      * Returns the search bar view.
      * @param parent the parent to attach the search bar view to.
      */
-    public abstract View getView(ViewGroup parent);
+    public View getView(ViewGroup parent) {
+        return null;
+    }
 
     /**
      * Focuses the search field to handle key events.
      */
-    public abstract void focusSearchField();
+    public void focusSearchField() {
+        mInput.requestFocus();
+        mInputMethodManager.showSoftInput(mInput, InputMethodManager.SHOW_IMPLICIT);
+    }
 
     /**
      * Returns whether the search field is focused.
      */
-    public abstract boolean isSearchFieldFocused();
-
-    /**
-     * Resets the search bar state.
-     */
-    public abstract void reset();
+    public boolean isSearchFieldFocused() {
+        return mInput.isFocused();
+    }
 
     /**
      * Returns whether the prediction bar should currently be visible depending on the state of
      * the search bar.
      */
-    @Deprecated
-    public abstract boolean shouldShowPredictionBar();
+    public boolean shouldShowPredictionBar() {
+        return false;
+    }
 
     /**
      * Callback for getting search results.
diff --git a/src/com/android/launcher3/allapps/DefaultAppSearchController.java b/src/com/android/launcher3/allapps/DefaultAppSearchController.java
index 3169f842a..57747e367 100644
--- a/src/com/android/launcher3/allapps/DefaultAppSearchController.java
+++ b/src/com/android/launcher3/allapps/DefaultAppSearchController.java
@@ -15,261 +15,12 @@
  */
 package com.android.launcher3.allapps;
 
-import android.content.Context;
-import android.text.Editable;
-import android.text.TextWatcher;
-import android.view.KeyEvent;
-import android.view.LayoutInflater;
-import android.view.View;
-import android.view.ViewGroup;
-import android.view.inputmethod.EditorInfo;
-import android.view.inputmethod.InputMethodManager;
-import android.widget.TextView;
-import com.android.launcher3.ExtendedEditText;
-import com.android.launcher3.R;
-import com.android.launcher3.Utilities;
-import com.android.launcher3.util.Thunk;
-
-import java.util.List;
-
-
 /**
  * The default search controller.
  */
-final class DefaultAppSearchController extends AllAppsSearchBarController
-        implements TextWatcher, TextView.OnEditorActionListener, View.OnClickListener {
-
-    private static final boolean ALLOW_SINGLE_APP_LAUNCH = true;
-
-    private static final int FADE_IN_DURATION = 175;
-    private static final int FADE_OUT_DURATION = 100;
-    private static final int SEARCH_TRANSLATION_X_DP = 18;
-
-    private final Context mContext;
-    @Thunk final InputMethodManager mInputMethodManager;
-
-    private DefaultAppSearchAlgorithm mSearchManager;
-
-    private ViewGroup mContainerView;
-    private View mSearchView;
-    @Thunk View mSearchBarContainerView;
-    private View mSearchButtonView;
-    private View mDismissSearchButtonView;
-    @Thunk
-    ExtendedEditText mSearchBarEditView;
-    @Thunk AllAppsRecyclerView mAppsRecyclerView;
-    @Thunk Runnable mFocusRecyclerViewRunnable = new Runnable() {
-        @Override
-        public void run() {
-            mAppsRecyclerView.requestFocus();
-        }
-    };
-
-    public DefaultAppSearchController(Context context, ViewGroup containerView,
-            AllAppsRecyclerView appsRecyclerView) {
-        mContext = context;
-        mInputMethodManager = (InputMethodManager)
-                mContext.getSystemService(Context.INPUT_METHOD_SERVICE);
-        mContainerView = containerView;
-        mAppsRecyclerView = appsRecyclerView;
-    }
-
-    @Override
-    public View getView(ViewGroup parent) {
-        LayoutInflater inflater = LayoutInflater.from(parent.getContext());
-        mSearchView = inflater.inflate(R.layout.all_apps_search_bar, parent, false);
-        mSearchView.setOnClickListener(this);
-
-        mSearchButtonView = mSearchView.findViewById(R.id.search_button);
-        mSearchBarContainerView = mSearchView.findViewById(R.id.search_container);
-        mDismissSearchButtonView = mSearchBarContainerView.findViewById(R.id.dismiss_search_button);
-        mDismissSearchButtonView.setOnClickListener(this);
-        mSearchBarEditView = (ExtendedEditText)
-                mSearchBarContainerView.findViewById(R.id.search_box_input);
-        mSearchBarEditView.addTextChangedListener(this);
-        mSearchBarEditView.setOnEditorActionListener(this);
-        mSearchBarEditView.setOnBackKeyListener(
-                new ExtendedEditText.OnBackKeyListener() {
-                    @Override
-                    public boolean onBackKey() {
-                        // Only hide the search field if there is no query, or if there
-                        // are no filtered results
-                        String query = Utilities.trim(
-                                mSearchBarEditView.getEditableText().toString());
-                        if (query.isEmpty() || mApps.hasNoFilteredResults()) {
-                            hideSearchField(true, mFocusRecyclerViewRunnable);
-                            return true;
-                        }
-                        return false;
-                    }
-                });
-        return mSearchView;
-    }
-
-    @Override
-    public void focusSearchField() {
-        mSearchBarEditView.requestFocus();
-        showSearchField();
-    }
-
-    @Override
-    public boolean isSearchFieldFocused() {
-        return mSearchBarEditView.isFocused();
-    }
-
-    @Override
-    protected void onInitialize() {
-        mSearchManager = new DefaultAppSearchAlgorithm(mApps.getApps());
-    }
-
-    @Override
-    public void reset() {
-        hideSearchField(false, null);
-    }
-
-    @Override
-    public boolean shouldShowPredictionBar() {
-        return false;
-    }
-
-    @Override
-    public void onClick(View v) {
-        if (v == mSearchView) {
-            showSearchField();
-        } else if (v == mDismissSearchButtonView) {
-            hideSearchField(true, mFocusRecyclerViewRunnable);
-        }
-    }
-
-    @Override
-    public void beforeTextChanged(CharSequence s, int start, int count, int after) {
-        // Do nothing
-    }
-
-    @Override
-    public void onTextChanged(CharSequence s, int start, int before, int count) {
-        // Do nothing
-    }
-
-    @Override
-    public void afterTextChanged(final Editable s) {
-        String query = s.toString();
-        if (query.isEmpty()) {
-            mSearchManager.cancel(true);
-            mCb.clearSearchResult();
-        } else {
-            mSearchManager.cancel(false);
-            mSearchManager.doSearch(query, mCb);
-        }
-    }
-
-    @Override
-    public boolean onEditorAction(TextView v, int actionId, KeyEvent event) {
-        // Skip if we disallow app-launch-on-enter
-        if (!ALLOW_SINGLE_APP_LAUNCH) {
-            return false;
-        }
-        // Skip if it's not the right action
-        if (actionId != EditorInfo.IME_ACTION_SEARCH) {
-            return false;
-        }
-        // Skip if there are more than one icon
-        if (mApps.getNumFilteredApps() > 1) {
-            return false;
-        }
-        // Otherwise, find the first icon, or fallback to the search-market-view and launch it
-        List<AlphabeticalAppsList.AdapterItem> items = mApps.getAdapterItems();
-        for (int i = 0; i < items.size(); i++) {
-            AlphabeticalAppsList.AdapterItem item = items.get(i);
-            switch (item.viewType) {
-                case AllAppsGridAdapter.ICON_VIEW_TYPE:
-                case AllAppsGridAdapter.SEARCH_MARKET_VIEW_TYPE:
-                    mAppsRecyclerView.getChildAt(i).performClick();
-                    mInputMethodManager.hideSoftInputFromWindow(
-                            mContainerView.getWindowToken(), 0);
-                    return true;
-            }
-        }
-        return false;
-    }
-
-    /**
-     * Focuses the search field.
-     */
-    private void showSearchField() {
-        // Show the search bar and focus the search
-        final int translationX = Utilities.pxFromDp(SEARCH_TRANSLATION_X_DP,
-                mContext.getResources().getDisplayMetrics());
-        mSearchBarContainerView.setVisibility(View.VISIBLE);
-        mSearchBarContainerView.setAlpha(0f);
-        mSearchBarContainerView.setTranslationX(translationX);
-        mSearchBarContainerView.animate()
-                .alpha(1f)
-                .translationX(0)
-                .setDuration(FADE_IN_DURATION)
-                .withLayer()
-                .withEndAction(new Runnable() {
-                    @Override
-                    public void run() {
-                        mSearchBarEditView.requestFocus();
-                        mInputMethodManager.showSoftInput(mSearchBarEditView,
-                                InputMethodManager.SHOW_IMPLICIT);
-                    }
-                });
-        mSearchButtonView.animate()
-                .alpha(0f)
-                .translationX(-translationX)
-                .setDuration(FADE_OUT_DURATION)
-                .withLayer();
-    }
-
-    /**
-     * Unfocuses the search field.
-     */
-    @Thunk void hideSearchField(boolean animated, final Runnable postAnimationRunnable) {
-        mSearchManager.cancel(true);
+public class DefaultAppSearchController extends AllAppsSearchBarController {
 
-        final boolean resetTextField = mSearchBarEditView.getText().toString().length() > 0;
-        final int translationX = Utilities.pxFromDp(SEARCH_TRANSLATION_X_DP,
-                mContext.getResources().getDisplayMetrics());
-        if (animated) {
-            // Hide the search bar and focus the recycler view
-            mSearchBarContainerView.animate()
-                    .alpha(0f)
-                    .translationX(0)
-                    .setDuration(FADE_IN_DURATION)
-                    .withLayer()
-                    .withEndAction(new Runnable() {
-                        @Override
-                        public void run() {
-                            mSearchBarContainerView.setVisibility(View.INVISIBLE);
-                            if (resetTextField) {
-                                mSearchBarEditView.setText("");
-                            }
-                            mCb.clearSearchResult();
-                            if (postAnimationRunnable != null) {
-                                postAnimationRunnable.run();
-                            }
-                        }
-                    });
-            mSearchButtonView.setTranslationX(-translationX);
-            mSearchButtonView.animate()
-                    .alpha(1f)
-                    .translationX(0)
-                    .setDuration(FADE_OUT_DURATION)
-                    .withLayer();
-        } else {
-            mSearchBarContainerView.setVisibility(View.INVISIBLE);
-            if (resetTextField) {
-                mSearchBarEditView.setText("");
-            }
-            mCb.clearSearchResult();
-            mSearchButtonView.setAlpha(1f);
-            mSearchButtonView.setTranslationX(0f);
-            if (postAnimationRunnable != null) {
-                postAnimationRunnable.run();
-            }
-        }
-        mInputMethodManager.hideSoftInputFromWindow(mContainerView.getWindowToken(), 0);
+    public DefaultAppSearchAlgorithm onInitializeSearch() {
+        return new DefaultAppSearchAlgorithm(mApps.getApps());
     }
 }
diff --git a/src/com/android/launcher3/allapps/HeaderElevationController.java b/src/com/android/launcher3/allapps/HeaderElevationController.java
new file mode 100644
index 000000000..07f583caa
--- /dev/null
+++ b/src/com/android/launcher3/allapps/HeaderElevationController.java
@@ -0,0 +1,101 @@
+package com.android.launcher3.allapps;
+
+import android.annotation.TargetApi;
+import android.content.res.Resources;
+import android.graphics.Rect;
+import android.graphics.drawable.GradientDrawable;
+import android.os.Build;
+import android.support.v7.widget.RecyclerView;
+import android.view.View;
+import android.view.ViewGroup;
+import android.view.ViewOutlineProvider;
+import android.widget.FrameLayout;
+
+import com.android.launcher3.R;
+
+/**
+ * Helper class for controlling the header elevation in response to RecyclerView scroll.
+ */
+public abstract class HeaderElevationController extends RecyclerView.OnScrollListener {
+
+    private int mCurrentY = 0;
+
+    public void reset() {
+        mCurrentY = 0;
+        onScroll(mCurrentY);
+    }
+
+    @Override
+    public final void onScrolled(RecyclerView recyclerView, int dx, int dy) {
+        mCurrentY += dy;
+        onScroll(mCurrentY);
+    }
+
+    public void updateBackgroundPadding(Rect bgPadding) { }
+
+    abstract void onScroll(int scrollY);
+
+    public static class ControllerV16 extends HeaderElevationController {
+
+        private final View mShadow;
+        private final float mScrollToElevation;
+
+        public ControllerV16(View header) {
+            Resources res = header.getContext().getResources();
+            mScrollToElevation = res.getDimension(R.dimen.all_apps_header_scroll_to_elevation);
+
+            mShadow = new View(header.getContext());
+            mShadow.setBackground(new GradientDrawable(
+                    GradientDrawable.Orientation.TOP_BOTTOM, new int[] {0x1E000000, 0x00000000}));
+            mShadow.setAlpha(0);
+
+            FrameLayout.LayoutParams lp = new FrameLayout.LayoutParams(
+                    FrameLayout.LayoutParams.MATCH_PARENT,
+                    res.getDimensionPixelSize(R.dimen.all_apps_header_shadow_height));
+            lp.topMargin = ((FrameLayout.LayoutParams) header.getLayoutParams()).height;
+
+            ((ViewGroup) header.getParent()).addView(mShadow, lp);
+        }
+
+        @Override
+        public void onScroll(int scrollY) {
+            float elevationPct = (float) Math.min(scrollY, mScrollToElevation) /
+                    mScrollToElevation;
+            mShadow.setAlpha(elevationPct);
+        }
+
+        @Override
+        public void updateBackgroundPadding(Rect bgPadding) {
+            FrameLayout.LayoutParams lp = (FrameLayout.LayoutParams) mShadow.getLayoutParams();
+            lp.leftMargin = bgPadding.left;
+            lp.rightMargin = bgPadding.right;
+            mShadow.requestLayout();
+        }
+    }
+
+    @TargetApi(Build.VERSION_CODES.LOLLIPOP)
+    public static class ControllerVL extends HeaderElevationController {
+
+        private final View mHeader;
+        private final float mMaxElevation;
+        private final float mScrollToElevation;
+
+        public ControllerVL(View header) {
+            mHeader = header;
+            mHeader.setOutlineProvider(ViewOutlineProvider.BOUNDS);
+
+            Resources res = header.getContext().getResources();
+            mMaxElevation = res.getDimension(R.dimen.all_apps_header_max_elevation);
+            mScrollToElevation = res.getDimension(R.dimen.all_apps_header_scroll_to_elevation);
+        }
+
+        @Override
+        public void onScroll(int scrollY) {
+            float elevationPct = Math.min(scrollY, mScrollToElevation) / mScrollToElevation;
+            float newElevation = mMaxElevation * elevationPct;
+            if (Float.compare(mHeader.getElevation(), newElevation) != 0) {
+                mHeader.setElevation(newElevation);
+            }
+        }
+    }
+}