Removing the section break UI support

This was an exploration for an alternative UI in all apps, where we
show section headers before every section. This was never released.

Change-Id: I2d36f1d078cc9a6f3ba6f0ec9655412182c9b016

11 files changed, 28 insertions, 489 deletions

diff --git a/res/layout/all_apps.xml b/res/layout/all_apps.xml
index 64d34e715..803a1b561 100644
--- a/res/layout/all_apps.xml
+++ b/res/layout/all_apps.xml
@@ -53,6 +53,7 @@
             android:clipToPadding="false"
             android:descendantFocusability="afterDescendants"
             android:focusable="true"
+            android:paddingEnd="@dimen/container_fastscroll_thumb_max_width"
             android:theme="@style/CustomOverscroll.Light" />
 
         <!-- Fast scroller popup -->
diff --git a/res/values-sw600dp/dimens.xml b/res/values-sw600dp/dimens.xml
index 283808805..ead666cf7 100644
--- a/res/values-sw600dp/dimens.xml
+++ b/res/values-sw600dp/dimens.xml
@@ -16,8 +16,6 @@
 
 <resources>
 <!-- All Apps -->
-    <dimen name="all_apps_grid_view_start_margin">0dp</dimen>
-    <dimen name="all_apps_grid_section_text_size">26sp</dimen>
     <dimen name="all_apps_background_canvas_width">850dp</dimen>
     <dimen name="all_apps_background_canvas_height">525dp</dimen>
 
diff --git a/res/values/dimens.xml b/res/values/dimens.xml
index 9967b7ea0..316e748bb 100644
--- a/res/values/dimens.xml
+++ b/res/values/dimens.xml
@@ -62,9 +62,6 @@
 
 <!-- All Apps -->
     <dimen name="all_apps_button_scale_down">0dp</dimen>
-    <dimen name="all_apps_grid_view_start_margin">0dp</dimen>
-    <dimen name="all_apps_grid_section_y_offset">8dp</dimen>
-    <dimen name="all_apps_grid_section_text_size">24sp</dimen>
     <dimen name="all_apps_search_bar_field_height">48dp</dimen>
     <dimen name="all_apps_search_bar_height">60dp</dimen>
     <dimen name="all_apps_search_bar_icon_margin_right">4dp</dimen>
diff --git a/src/com/android/launcher3/BaseRecyclerView.java b/src/com/android/launcher3/BaseRecyclerView.java
index 9bdbe2580..4e39ed3e5 100644
--- a/src/com/android/launcher3/BaseRecyclerView.java
+++ b/src/com/android/launcher3/BaseRecyclerView.java
@@ -173,13 +173,6 @@ public abstract class BaseRecyclerView extends RecyclerView
     }
 
     /**
-     * Returns the scroll bar width when the user is scrolling.
-     */
-    public int getMaxScrollbarWidth() {
-        return mScrollbar.getThumbMaxWidth();
-    }
-
-    /**
      * Returns the visible height of the recycler view:
      *   VisibleHeight = View height - top padding - bottom padding
      */
diff --git a/src/com/android/launcher3/BaseRecyclerViewFastScrollBar.java b/src/com/android/launcher3/BaseRecyclerViewFastScrollBar.java
index 770166dae..263e132c8 100644
--- a/src/com/android/launcher3/BaseRecyclerViewFastScrollBar.java
+++ b/src/com/android/launcher3/BaseRecyclerViewFastScrollBar.java
@@ -177,10 +177,6 @@ public class BaseRecyclerViewFastScrollBar {
         return mThumbHeight;
     }
 
-    public int getThumbMaxWidth() {
-        return mMaxWidth;
-    }
-
     public boolean isDraggingThumb() {
         return mIsDragging;
     }
diff --git a/src/com/android/launcher3/allapps/AllAppsContainerView.java b/src/com/android/launcher3/allapps/AllAppsContainerView.java
index 5c9e3f74e..8ef9312fc 100644
--- a/src/com/android/launcher3/allapps/AllAppsContainerView.java
+++ b/src/com/android/launcher3/allapps/AllAppsContainerView.java
@@ -16,7 +16,6 @@
 package com.android.launcher3.allapps;
 
 import android.content.Context;
-import android.content.res.Resources;
 import android.graphics.Rect;
 import android.support.v7.widget.RecyclerView;
 import android.text.Selection;
@@ -56,78 +55,9 @@ import com.android.launcher3.shortcuts.DeepShortcutsContainer;
 import com.android.launcher3.userevent.nano.LauncherLogProto.Target;
 import com.android.launcher3.util.ComponentKey;
 
-import java.nio.charset.Charset;
-import java.nio.charset.CharsetEncoder;
 import java.util.ArrayList;
 import java.util.List;
 
-
-/**
- * A merge algorithm that merges every section indiscriminately.
- */
-final class FullMergeAlgorithm implements AlphabeticalAppsList.MergeAlgorithm {
-
-    @Override
-    public boolean continueMerging(AlphabeticalAppsList.SectionInfo section,
-            AlphabeticalAppsList.SectionInfo withSection,
-            int sectionAppCount, int numAppsPerRow, int mergeCount) {
-        // Don't merge the predicted apps
-        if (section.firstAppItem.viewType != AllAppsGridAdapter.VIEW_TYPE_ICON) {
-            return false;
-        }
-        // Otherwise, merge every other section
-        return true;
-    }
-}
-
-/**
- * The logic we use to merge multiple sections.  We only merge sections when their final row
- * contains less than a certain number of icons, and stop at a specified max number of merges.
- * In addition, we will try and not merge sections that identify apps from different scripts.
- */
-final class SimpleSectionMergeAlgorithm implements AlphabeticalAppsList.MergeAlgorithm {
-
-    private int mMinAppsPerRow;
-    private int mMinRowsInMergedSection;
-    private int mMaxAllowableMerges;
-    private CharsetEncoder mAsciiEncoder;
-
-    public SimpleSectionMergeAlgorithm(int minAppsPerRow, int minRowsInMergedSection, int maxNumMerges) {
-        mMinAppsPerRow = minAppsPerRow;
-        mMinRowsInMergedSection = minRowsInMergedSection;
-        mMaxAllowableMerges = maxNumMerges;
-        mAsciiEncoder = Charset.forName("US-ASCII").newEncoder();
-    }
-
-    @Override
-    public boolean continueMerging(AlphabeticalAppsList.SectionInfo section,
-            AlphabeticalAppsList.SectionInfo withSection,
-            int sectionAppCount, int numAppsPerRow, int mergeCount) {
-        // Don't merge the predicted apps
-        if (section.firstAppItem.viewType != AllAppsGridAdapter.VIEW_TYPE_ICON) {
-            return false;
-        }
-
-        // Continue merging if the number of hanging apps on the final row is less than some
-        // fixed number (ragged), the merged rows has yet to exceed some minimum row count,
-        // and while the number of merged sections is less than some fixed number of merges
-        int rows = sectionAppCount / numAppsPerRow;
-        int cols = sectionAppCount % numAppsPerRow;
-
-        // Ensure that we do not merge across scripts, currently we only allow for english and
-        // native scripts so we can test if both can just be ascii encoded
-        boolean isCrossScript = false;
-        if (section.firstAppItem != null && withSection.firstAppItem != null) {
-            isCrossScript = mAsciiEncoder.canEncode(section.firstAppItem.sectionName) !=
-                    mAsciiEncoder.canEncode(withSection.firstAppItem.sectionName);
-        }
-        return (0 < cols && cols < mMinAppsPerRow) &&
-                rows < mMinRowsInMergedSection &&
-                mergeCount < mMaxAllowableMerges &&
-                !isCrossScript;
-    }
-}
-
 /**
  * The all apps view container.
  */
@@ -135,14 +65,10 @@ public class AllAppsContainerView extends BaseContainerView implements DragSourc
         LauncherTransitionable, View.OnLongClickListener, AllAppsSearchBarController.Callbacks,
         Insettable {
 
-    private static final int MIN_ROWS_IN_MERGED_SECTION_PHONE = 3;
-    private static final int MAX_NUM_MERGES_PHONE = 2;
-
     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;
@@ -153,7 +79,6 @@ public class AllAppsContainerView extends BaseContainerView implements DragSourc
 
     private SpannableStringBuilder mSearchQueryBuilder = null;
 
-    private int mSectionNamesMargin;
     private int mNumAppsPerRow;
     private int mNumPredictedAppsPerRow;
 
@@ -167,15 +92,12 @@ public class AllAppsContainerView extends BaseContainerView implements DragSourc
 
     public AllAppsContainerView(Context context, AttributeSet attrs, int defStyleAttr) {
         super(context, attrs, defStyleAttr);
-        Resources res = context.getResources();
 
         mLauncher = Launcher.getLauncher(context);
-        mSectionNamesMargin = res.getDimensionPixelSize(R.dimen.all_apps_grid_view_start_margin);
         mApps = new AlphabeticalAppsList(context);
         mAdapter = new AllAppsGridAdapter(mLauncher, mApps, mLauncher, this);
         mApps.setAdapter(mAdapter);
         mLayoutManager = mAdapter.getLayoutManager();
-        mItemDecoration = mAdapter.getItemDecoration();
         mSearchQueryBuilder = new SpannableStringBuilder();
         Selection.setSelection(mSearchQueryBuilder, 0);
     }
@@ -337,10 +259,6 @@ public class AllAppsContainerView extends BaseContainerView implements DragSourc
         mAppsRecyclerView.addOnScrollListener(mElevationController);
         mAppsRecyclerView.setElevationController(mElevationController);
 
-        if (mItemDecoration != null) {
-            mAppsRecyclerView.addItemDecoration(mItemDecoration);
-        }
-
         FocusedItemDecorator focusedItemDecorator = new FocusedItemDecorator(mAppsRecyclerView);
         mAppsRecyclerView.addItemDecoration(focusedItemDecorator);
         mAppsRecyclerView.preMeasureViews(mAdapter);
@@ -351,14 +269,6 @@ public class AllAppsContainerView extends BaseContainerView implements DragSourc
             getContentView().setVisibility(View.VISIBLE);
             getContentView().setBackground(null);
         }
-
-        int maxScrollBarWidth = mAppsRecyclerView.getMaxScrollbarWidth();
-        int startInset = Math.max(mSectionNamesMargin, maxScrollBarWidth);
-        if (Utilities.isRtl(getResources())) {
-            mAppsRecyclerView.setPadding(maxScrollBarWidth, 0, startInset, 0);
-        } else {
-            mAppsRecyclerView.setPadding(startInset, 0, maxScrollBarWidth, 0);
-        }
     }
 
     @Override
@@ -381,7 +291,7 @@ public class AllAppsContainerView extends BaseContainerView implements DragSourc
 
                 mAppsRecyclerView.setNumAppsPerRow(grid, mNumAppsPerRow);
                 mAdapter.setNumAppsPerRow(mNumAppsPerRow);
-                mApps.setNumAppsPerRow(mNumAppsPerRow, mNumPredictedAppsPerRow, new FullMergeAlgorithm());
+                mApps.setNumAppsPerRow(mNumAppsPerRow, mNumPredictedAppsPerRow);
             }
             if (!grid.isVerticalBarLayout()) {
                 MarginLayoutParams searchContainerLp =
@@ -396,25 +306,15 @@ public class AllAppsContainerView extends BaseContainerView implements DragSourc
         // --- remove START when {@code FeatureFlags.LAUNCHER3_ALL_APPS_PULL_UP} is enabled. ---
 
         // Update the number of items in the grid before we measure the view
-        // TODO: mSectionNamesMargin is currently 0, but also account for it,
-        // if it's enabled in the future.
         grid.updateAppsViewNumCols();
         if (mNumAppsPerRow != grid.allAppsNumCols ||
                 mNumPredictedAppsPerRow != grid.allAppsNumPredictiveCols) {
             mNumAppsPerRow = grid.allAppsNumCols;
             mNumPredictedAppsPerRow = grid.allAppsNumPredictiveCols;
 
-            // If there is a start margin to draw section names, determine how we are going to merge
-            // app sections
-            boolean mergeSectionsFully = mSectionNamesMargin == 0 || !grid.isPhone;
-            AlphabeticalAppsList.MergeAlgorithm mergeAlgorithm = mergeSectionsFully ?
-                    new FullMergeAlgorithm() :
-                    new SimpleSectionMergeAlgorithm((int) Math.ceil(mNumAppsPerRow / 2f),
-                            MIN_ROWS_IN_MERGED_SECTION_PHONE, MAX_NUM_MERGES_PHONE);
-
             mAppsRecyclerView.setNumAppsPerRow(grid, mNumAppsPerRow);
             mAdapter.setNumAppsPerRow(mNumAppsPerRow);
-            mApps.setNumAppsPerRow(mNumAppsPerRow, mNumPredictedAppsPerRow, mergeAlgorithm);
+            mApps.setNumAppsPerRow(mNumAppsPerRow, mNumPredictedAppsPerRow);
         }
 
         // --- remove END when {@code FeatureFlags.LAUNCHER3_ALL_APPS_PULL_UP} is enabled. ---
diff --git a/src/com/android/launcher3/allapps/AllAppsFastScrollHelper.java b/src/com/android/launcher3/allapps/AllAppsFastScrollHelper.java
index 808de476b..28b7685ed 100644
--- a/src/com/android/launcher3/allapps/AllAppsFastScrollHelper.java
+++ b/src/com/android/launcher3/allapps/AllAppsFastScrollHelper.java
@@ -29,7 +29,6 @@ public class AllAppsFastScrollHelper implements AllAppsGridAdapter.BindViewCallb
 
     private static final int INITIAL_TOUCH_SETTLING_DURATION = 100;
     private static final int REPEAT_TOUCH_SETTLING_DURATION = 200;
-    private static final float FAST_SCROLL_TOUCH_VELOCITY_BARRIER = 1900f;
 
     private AllAppsRecyclerView mRv;
     private AlphabeticalAppsList mApps;
@@ -187,9 +186,9 @@ public class AllAppsFastScrollHelper implements AllAppsGridAdapter.BindViewCallb
     public void onBindView(AllAppsGridAdapter.ViewHolder holder) {
         // Update newly bound views to the current fast scroll state if we are fast scrolling
         if (mCurrentFastScrollSection != null || mTargetFastScrollSection != null) {
-            if (holder.mContent instanceof BaseRecyclerViewFastScrollBar.FastScrollFocusableView) {
+            if (holder.itemView instanceof BaseRecyclerViewFastScrollBar.FastScrollFocusableView) {
                 BaseRecyclerViewFastScrollBar.FastScrollFocusableView v =
-                        (BaseRecyclerViewFastScrollBar.FastScrollFocusableView) holder.mContent;
+                        (BaseRecyclerViewFastScrollBar.FastScrollFocusableView) holder.itemView;
                 updateViewFastScrollFocusState(v, holder.getPosition(), false /* animated */);
                 mTrackedFastScrollViews.add(v);
             }
diff --git a/src/com/android/launcher3/allapps/AllAppsGridAdapter.java b/src/com/android/launcher3/allapps/AllAppsGridAdapter.java
index 7b6aef16d..bd877f248 100644
--- a/src/com/android/launcher3/allapps/AllAppsGridAdapter.java
+++ b/src/com/android/launcher3/allapps/AllAppsGridAdapter.java
@@ -18,10 +18,7 @@ package com.android.launcher3.allapps;
 import android.content.Context;
 import android.content.Intent;
 import android.content.res.Resources;
-import android.graphics.Canvas;
-import android.graphics.Paint;
 import android.graphics.Point;
-import android.graphics.PointF;
 import android.graphics.Rect;
 import android.support.v4.view.accessibility.AccessibilityEventCompat;
 import android.support.v4.view.accessibility.AccessibilityRecordCompat;
@@ -41,10 +38,6 @@ import com.android.launcher3.BubbleTextView;
 import com.android.launcher3.DeviceProfile;
 import com.android.launcher3.Launcher;
 import com.android.launcher3.R;
-import com.android.launcher3.Utilities;
-
-import java.util.HashMap;
-import java.util.List;
 
 /**
  * The grid view adapter of all the apps.
@@ -52,10 +45,7 @@ import java.util.List;
 public class AllAppsGridAdapter extends RecyclerView.Adapter<AllAppsGridAdapter.ViewHolder> {
 
     public static final String TAG = "AppsGridAdapter";
-    private static final boolean DEBUG = false;
 
-    // A section break in the grid
-    public static final int VIEW_TYPE_SECTION_BREAK = 1 << 0;
     // A normal icon
     public static final int VIEW_TYPE_ICON = 1 << 1;
     // A prediction icon
@@ -78,25 +68,22 @@ public class AllAppsGridAdapter extends RecyclerView.Adapter<AllAppsGridAdapter.
     // Common view type masks
     public static final int VIEW_TYPE_MASK_DIVIDER = VIEW_TYPE_SEARCH_DIVIDER
             | VIEW_TYPE_SEARCH_MARKET_DIVIDER
-            | VIEW_TYPE_PREDICTION_DIVIDER
-            | VIEW_TYPE_SECTION_BREAK;
+            | VIEW_TYPE_PREDICTION_DIVIDER;
     public static final int VIEW_TYPE_MASK_ICON = VIEW_TYPE_ICON
             | VIEW_TYPE_PREDICTION_ICON;
 
 
     public interface BindViewCallback {
-        public void onBindView(ViewHolder holder);
+        void onBindView(ViewHolder holder);
     }
 
     /**
      * ViewHolder for each icon.
      */
     public static class ViewHolder extends RecyclerView.ViewHolder {
-        public View mContent;
 
         public ViewHolder(View v) {
             super(v);
-            mContent = v;
         }
     }
 
@@ -158,189 +145,14 @@ public class AllAppsGridAdapter extends RecyclerView.Adapter<AllAppsGridAdapter.
         }
     }
 
-    /**
-     * Helper class to draw the section headers
-     */
-    public class GridItemDecoration extends RecyclerView.ItemDecoration {
-
-        private static final boolean DEBUG_SECTION_MARGIN = false;
-        private static final boolean FADE_OUT_SECTIONS = false;
-
-        private HashMap<String, PointF> mCachedSectionBounds = new HashMap<>();
-        private Rect mTmpBounds = new Rect();
-
-        @Override
-        public void onDraw(Canvas c, RecyclerView parent, RecyclerView.State state) {
-            if (mApps.hasFilter() || mAppsPerRow == 0) {
-                return;
-            }
-
-            if (DEBUG_SECTION_MARGIN) {
-                Paint p = new Paint();
-                p.setColor(0x33ff0000);
-                c.drawRect(mBackgroundPadding.left, 0, mBackgroundPadding.left + mSectionNamesMargin,
-                        parent.getMeasuredHeight(), p);
-            }
-
-            List<AlphabeticalAppsList.AdapterItem> items = mApps.getAdapterItems();
-            boolean showSectionNames = mSectionNamesMargin > 0;
-            int childCount = parent.getChildCount();
-            int lastSectionTop = 0;
-            int lastSectionHeight = 0;
-            for (int i = 0; i < childCount; i++) {
-                View child = parent.getChildAt(i);
-                ViewHolder holder = (ViewHolder) parent.getChildViewHolder(child);
-                if (!isValidHolderAndChild(holder, child, items)) {
-                    continue;
-                }
-
-                if (showSectionNames && shouldDrawItemSection(holder, i, items)) {
-                    // At this point, we only draw sections for each section break;
-                    int viewTopOffset = (2 * child.getPaddingTop());
-                    int pos = holder.getPosition();
-                    AlphabeticalAppsList.AdapterItem item = items.get(pos);
-                    AlphabeticalAppsList.SectionInfo sectionInfo = item.sectionInfo;
-
-                    // Draw all the sections for this index
-                    String lastSectionName = item.sectionName;
-                    for (int j = item.sectionAppIndex; j < sectionInfo.numApps; j++, pos++) {
-                        AlphabeticalAppsList.AdapterItem nextItem = items.get(pos);
-                        String sectionName = nextItem.sectionName;
-                        if (nextItem.sectionInfo != sectionInfo) {
-                            break;
-                        }
-                        if (j > item.sectionAppIndex && sectionName.equals(lastSectionName)) {
-                            continue;
-                        }
-
-                        // Find the section name bounds
-                        PointF sectionBounds = getAndCacheSectionBounds(sectionName);
-
-                        // Calculate where to draw the section
-                        int sectionBaseline = (int) (viewTopOffset + sectionBounds.y);
-                        int x = mIsRtl ?
-                                parent.getWidth() - mBackgroundPadding.left - mSectionNamesMargin :
-                                mBackgroundPadding.left;
-                        x += (int) ((mSectionNamesMargin - sectionBounds.x) / 2f);
-                        int y = child.getTop() + sectionBaseline;
-
-                        // Determine whether this is the last row with apps in that section, if
-                        // so, then fix the section to the row allowing it to scroll past the
-                        // baseline, otherwise, bound it to the baseline so it's in the viewport
-                        int appIndexInSection = items.get(pos).sectionAppIndex;
-                        int nextRowPos = Math.min(items.size() - 1,
-                                pos + mAppsPerRow - (appIndexInSection % mAppsPerRow));
-                        AlphabeticalAppsList.AdapterItem nextRowItem = items.get(nextRowPos);
-                        boolean fixedToRow = !sectionName.equals(nextRowItem.sectionName);
-                        if (!fixedToRow) {
-                            y = Math.max(sectionBaseline, y);
-                        }
-
-                        // In addition, if it overlaps with the last section that was drawn, then
-                        // offset it so that it does not overlap
-                        if (lastSectionHeight > 0 && y <= (lastSectionTop + lastSectionHeight)) {
-                            y += lastSectionTop - y + lastSectionHeight;
-                        }
-
-                        // Draw the section header
-                        if (FADE_OUT_SECTIONS) {
-                            int alpha = 255;
-                            if (fixedToRow) {
-                                alpha = Math.min(255,
-                                        (int) (255 * (Math.max(0, y) / (float) sectionBaseline)));
-                            }
-                            mSectionTextPaint.setAlpha(alpha);
-                        }
-                        c.drawText(sectionName, x, y, mSectionTextPaint);
-
-                        lastSectionTop = y;
-                        lastSectionHeight = (int) (sectionBounds.y + mSectionHeaderOffset);
-                        lastSectionName = sectionName;
-                    }
-                    i += (sectionInfo.numApps - item.sectionAppIndex);
-                }
-            }
-        }
-
-        @Override
-        public void getItemOffsets(Rect outRect, View view, RecyclerView parent,
-                RecyclerView.State state) {
-            // Do nothing
-        }
-
-        /**
-         * Given a section name, return the bounds of the given section name.
-         */
-        private PointF getAndCacheSectionBounds(String sectionName) {
-            PointF bounds = mCachedSectionBounds.get(sectionName);
-            if (bounds == null) {
-                mSectionTextPaint.getTextBounds(sectionName, 0, sectionName.length(), mTmpBounds);
-                bounds = new PointF(mSectionTextPaint.measureText(sectionName), mTmpBounds.height());
-                mCachedSectionBounds.put(sectionName, bounds);
-            }
-            return bounds;
-        }
-
-        /**
-         * Returns whether we consider this a valid view holder for us to draw a divider or section for.
-         */
-        private boolean isValidHolderAndChild(ViewHolder holder, View child,
-                List<AlphabeticalAppsList.AdapterItem> items) {
-            // Ensure item is not already removed
-            GridLayoutManager.LayoutParams lp = (GridLayoutManager.LayoutParams)
-                    child.getLayoutParams();
-            if (lp.isItemRemoved()) {
-                return false;
-            }
-            // Ensure we have a valid holder
-            if (holder == null) {
-                return false;
-            }
-            // Ensure we have a holder position
-            int pos = holder.getPosition();
-            if (pos < 0 || pos >= items.size()) {
-                return false;
-            }
-            return true;
-        }
-
-        /**
-         * Returns whether to draw the section for the given child.
-         */
-        private boolean shouldDrawItemSection(ViewHolder holder, int childIndex,
-                List<AlphabeticalAppsList.AdapterItem> items) {
-            int pos = holder.getPosition();
-            AlphabeticalAppsList.AdapterItem item = items.get(pos);
-
-            // Ensure it's an icon
-            if (item.viewType != AllAppsGridAdapter.VIEW_TYPE_ICON) {
-                return false;
-            }
-            // Draw the section header for the first item in each section
-            return (childIndex == 0) ||
-                    (items.get(pos - 1).viewType == AllAppsGridAdapter.VIEW_TYPE_SECTION_BREAK);
-        }
-    }
-
     private final Launcher mLauncher;
     private final LayoutInflater mLayoutInflater;
     private final AlphabeticalAppsList mApps;
     private final GridLayoutManager mGridLayoutMgr;
     private final GridSpanSizer mGridSizer;
-    private final GridItemDecoration mItemDecoration;
     private final View.OnClickListener mIconClickListener;
     private final View.OnLongClickListener mIconLongClickListener;
 
-    private final Rect mBackgroundPadding = new Rect();
-    private final boolean mIsRtl;
-
-    // Section drawing
-    @Deprecated
-    private final int mSectionNamesMargin;
-    @Deprecated
-    private final int mSectionHeaderOffset;
-    private final Paint mSectionTextPaint;
-
     private int mAppsPerRow;
 
     private BindViewCallback mBindViewCallback;
@@ -361,18 +173,9 @@ public class AllAppsGridAdapter extends RecyclerView.Adapter<AllAppsGridAdapter.
         mGridSizer = new GridSpanSizer();
         mGridLayoutMgr = new AppsGridLayoutManager(launcher);
         mGridLayoutMgr.setSpanSizeLookup(mGridSizer);
-        mItemDecoration = new GridItemDecoration();
         mLayoutInflater = LayoutInflater.from(launcher);
         mIconClickListener = iconClickListener;
         mIconLongClickListener = iconLongClickListener;
-        mSectionNamesMargin = res.getDimensionPixelSize(R.dimen.all_apps_grid_view_start_margin);
-        mSectionHeaderOffset = res.getDimensionPixelSize(R.dimen.all_apps_grid_section_y_offset);
-        mIsRtl = Utilities.isRtl(res);
-
-        mSectionTextPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
-        mSectionTextPaint.setTextSize(res.getDimensionPixelSize(
-                R.dimen.all_apps_grid_section_text_size));
-        mSectionTextPaint.setColor(Utilities.getColorAccent(launcher));
     }
 
     public static boolean isDividerViewType(int viewType) {
@@ -421,33 +224,15 @@ public class AllAppsGridAdapter extends RecyclerView.Adapter<AllAppsGridAdapter.
     }
 
     /**
-     * Notifies the adapter of the background padding so that it can draw things correctly in the
-     * item decorator.
-     */
-    public void updateBackgroundPadding(Rect padding) {
-        mBackgroundPadding.set(padding);
-    }
-
-    /**
      * Returns the grid layout manager.
      */
     public GridLayoutManager getLayoutManager() {
         return mGridLayoutMgr;
     }
 
-    /**
-     * Returns the item decoration for the recycler view.
-     */
-    public RecyclerView.ItemDecoration getItemDecoration() {
-        // We don't draw any headers when we are uncomfortably dense
-        return mItemDecoration;
-    }
-
     @Override
     public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
         switch (viewType) {
-            case VIEW_TYPE_SECTION_BREAK:
-                return new ViewHolder(new View(parent.getContext()));
             case VIEW_TYPE_ICON:
                 /* falls through */
             case VIEW_TYPE_PREDICTION_ICON: {
@@ -499,26 +284,26 @@ public class AllAppsGridAdapter extends RecyclerView.Adapter<AllAppsGridAdapter.
         switch (holder.getItemViewType()) {
             case VIEW_TYPE_ICON: {
                 AppInfo info = mApps.getAdapterItems().get(position).appInfo;
-                BubbleTextView icon = (BubbleTextView) holder.mContent;
+                BubbleTextView icon = (BubbleTextView) holder.itemView;
                 icon.applyFromApplicationInfo(info);
                 icon.setAccessibilityDelegate(mLauncher.getAccessibilityDelegate());
                 break;
             }
             case VIEW_TYPE_PREDICTION_ICON: {
                 AppInfo info = mApps.getAdapterItems().get(position).appInfo;
-                BubbleTextView icon = (BubbleTextView) holder.mContent;
+                BubbleTextView icon = (BubbleTextView) holder.itemView;
                 icon.applyFromApplicationInfo(info);
                 icon.setAccessibilityDelegate(mLauncher.getAccessibilityDelegate());
                 break;
             }
             case VIEW_TYPE_EMPTY_SEARCH:
-                TextView emptyViewText = (TextView) holder.mContent;
+                TextView emptyViewText = (TextView) holder.itemView;
                 emptyViewText.setText(mEmptySearchMessage);
                 emptyViewText.setGravity(mApps.hasNoFilteredResults() ? Gravity.CENTER :
                         Gravity.START | Gravity.CENTER_VERTICAL);
                 break;
             case VIEW_TYPE_SEARCH_MARKET:
-                TextView searchView = (TextView) holder.mContent;
+                TextView searchView = (TextView) holder.itemView;
                 if (mMarketSearchIntent != null) {
                     searchView.setVisibility(View.VISIBLE);
                 } else {
diff --git a/src/com/android/launcher3/allapps/AllAppsRecyclerView.java b/src/com/android/launcher3/allapps/AllAppsRecyclerView.java
index 5a9ea6bb3..a32a9b144 100644
--- a/src/com/android/launcher3/allapps/AllAppsRecyclerView.java
+++ b/src/com/android/launcher3/allapps/AllAppsRecyclerView.java
@@ -101,7 +101,6 @@ public class AllAppsRecyclerView extends BaseRecyclerView {
         pool.setMaxRecycledViews(AllAppsGridAdapter.VIEW_TYPE_ICON, approxRows * mNumAppsPerRow);
         pool.setMaxRecycledViews(AllAppsGridAdapter.VIEW_TYPE_PREDICTION_ICON, mNumAppsPerRow);
         pool.setMaxRecycledViews(AllAppsGridAdapter.VIEW_TYPE_PREDICTION_DIVIDER, 1);
-        pool.setMaxRecycledViews(AllAppsGridAdapter.VIEW_TYPE_SECTION_BREAK, approxRows);
     }
 
     /**
@@ -116,21 +115,21 @@ public class AllAppsRecyclerView extends BaseRecyclerView {
 
         // Icons
         BubbleTextView icon = (BubbleTextView) adapter.onCreateViewHolder(this,
-                AllAppsGridAdapter.VIEW_TYPE_ICON).mContent;
+                AllAppsGridAdapter.VIEW_TYPE_ICON).itemView;
         int iconHeight = icon.getLayoutParams().height;
         mViewHeights.put(AllAppsGridAdapter.VIEW_TYPE_ICON, iconHeight);
         mViewHeights.put(AllAppsGridAdapter.VIEW_TYPE_PREDICTION_ICON, iconHeight);
 
         // Search divider
         View searchDivider = adapter.onCreateViewHolder(this,
-                AllAppsGridAdapter.VIEW_TYPE_SEARCH_DIVIDER).mContent;
+                AllAppsGridAdapter.VIEW_TYPE_SEARCH_DIVIDER).itemView;
         searchDivider.measure(widthMeasureSpec, heightMeasureSpec);
         int searchDividerHeight = searchDivider.getMeasuredHeight();
         mViewHeights.put(AllAppsGridAdapter.VIEW_TYPE_SEARCH_DIVIDER, searchDividerHeight);
 
         // Generic dividers
         View divider = adapter.onCreateViewHolder(this,
-                AllAppsGridAdapter.VIEW_TYPE_PREDICTION_DIVIDER).mContent;
+                AllAppsGridAdapter.VIEW_TYPE_PREDICTION_DIVIDER).itemView;
         divider.measure(widthMeasureSpec, heightMeasureSpec);
         int dividerHeight = divider.getMeasuredHeight();
         mViewHeights.put(AllAppsGridAdapter.VIEW_TYPE_PREDICTION_DIVIDER, dividerHeight);
@@ -138,18 +137,15 @@ public class AllAppsRecyclerView extends BaseRecyclerView {
 
         // Search views
         View emptySearch = adapter.onCreateViewHolder(this,
-                AllAppsGridAdapter.VIEW_TYPE_EMPTY_SEARCH).mContent;
+                AllAppsGridAdapter.VIEW_TYPE_EMPTY_SEARCH).itemView;
         emptySearch.measure(widthMeasureSpec, heightMeasureSpec);
         mViewHeights.put(AllAppsGridAdapter.VIEW_TYPE_EMPTY_SEARCH,
                 emptySearch.getMeasuredHeight());
         View searchMarket = adapter.onCreateViewHolder(this,
-                AllAppsGridAdapter.VIEW_TYPE_SEARCH_MARKET).mContent;
+                AllAppsGridAdapter.VIEW_TYPE_SEARCH_MARKET).itemView;
         searchMarket.measure(widthMeasureSpec, heightMeasureSpec);
         mViewHeights.put(AllAppsGridAdapter.VIEW_TYPE_SEARCH_MARKET,
                 searchMarket.getMeasuredHeight());
-
-        // Section breaks
-        mViewHeights.put(AllAppsGridAdapter.VIEW_TYPE_SECTION_BREAK, 0);
     }
 
     /**
diff --git a/src/com/android/launcher3/allapps/AlphabeticalAppsList.java b/src/com/android/launcher3/allapps/AlphabeticalAppsList.java
index d19cf02ed..5a28e5c01 100644
--- a/src/com/android/launcher3/allapps/AlphabeticalAppsList.java
+++ b/src/com/android/launcher3/allapps/AlphabeticalAppsList.java
@@ -49,18 +49,6 @@ public class AlphabeticalAppsList {
     private final int mFastScrollDistributionMode = FAST_SCROLL_FRACTION_DISTRIBUTE_BY_NUM_SECTIONS;
 
     /**
-     * Info about a section in the alphabetic list
-     */
-    public static class SectionInfo {
-        // The number of applications in this section
-        public int numApps;
-        // The section break AdapterItem for this section
-        public AdapterItem sectionBreakItem;
-        // The first app AdapterItem for this section
-        public AdapterItem firstAppItem;
-    }
-
-    /**
      * Info about a fast scroller section, depending if sections are merged, the fast scroller
      * sections will not be the same set as the section headers.
      */
@@ -87,16 +75,10 @@ public class AlphabeticalAppsList {
         // The type of this item
         public int viewType;
 
-        /** Section & App properties */
-        // The section for this item
-        public SectionInfo sectionInfo;
-
         /** App-only properties */
         // The section name of this app.  Note that there can be multiple items with different
         // sectionNames in the same section
         public String sectionName = null;
-        // The index of this app in the section
-        public int sectionAppIndex = -1;
         // The row that this item shows up on
         public int rowIndex;
         // The index of this app in the row
@@ -106,30 +88,19 @@ public class AlphabeticalAppsList {
         // The index of this app not including sections
         public int appIndex = -1;
 
-        public static AdapterItem asSectionBreak(int pos, SectionInfo section) {
-            AdapterItem item = new AdapterItem();
-            item.viewType = AllAppsGridAdapter.VIEW_TYPE_SECTION_BREAK;
-            item.position = pos;
-            item.sectionInfo = section;
-            section.sectionBreakItem = item;
-            return item;
-        }
-
-        public static AdapterItem asPredictedApp(int pos, SectionInfo section, String sectionName,
-                int sectionAppIndex, AppInfo appInfo, int appIndex) {
-            AdapterItem item = asApp(pos, section, sectionName, sectionAppIndex, appInfo, appIndex);
+        public static AdapterItem asPredictedApp(int pos, String sectionName, AppInfo appInfo,
+                int appIndex) {
+            AdapterItem item = asApp(pos, sectionName, appInfo, appIndex);
             item.viewType = AllAppsGridAdapter.VIEW_TYPE_PREDICTION_ICON;
             return item;
         }
 
-        public static AdapterItem asApp(int pos, SectionInfo section, String sectionName,
-                int sectionAppIndex, AppInfo appInfo, int appIndex) {
+        public static AdapterItem asApp(int pos, String sectionName, AppInfo appInfo,
+                int appIndex) {
             AdapterItem item = new AdapterItem();
             item.viewType = AllAppsGridAdapter.VIEW_TYPE_ICON;
             item.position = pos;
-            item.sectionInfo = section;
             item.sectionName = sectionName;
-            item.sectionAppIndex = sectionAppIndex;
             item.appInfo = appInfo;
             item.appIndex = appIndex;
             return item;
@@ -171,14 +142,6 @@ public class AlphabeticalAppsList {
         }
     }
 
-    /**
-     * Common interface for different merging strategies.
-     */
-    public interface MergeAlgorithm {
-        boolean continueMerging(SectionInfo section, SectionInfo withSection,
-                int sectionAppCount, int numAppsPerRow, int mergeCount);
-    }
-
     private Launcher mLauncher;
 
     // The set of apps from the system not including predictions
@@ -189,8 +152,6 @@ public class AlphabeticalAppsList {
     private List<AppInfo> mFilteredApps = new ArrayList<>();
     // The current set of adapter items
     private List<AdapterItem> mAdapterItems = new ArrayList<>();
-    // The set of sections for the apps with the current filter
-    private List<SectionInfo> mSections = new ArrayList<>();
     // The set of sections that we allow fast-scrolling to (includes non-merged sections)
     private List<FastScrollSectionInfo> mFastScrollerSections = new ArrayList<>();
     // The set of predicted app component names
@@ -203,7 +164,6 @@ public class AlphabeticalAppsList {
     private AllAppsGridAdapter mAdapter;
     private AlphabeticIndexCompat mIndexer;
     private AppNameComparator mAppNameComparator;
-    private MergeAlgorithm mMergeAlgorithm;
     private int mNumAppsPerRow;
     private int mNumPredictedAppsPerRow;
     private int mNumAppRowsInAdapter;
@@ -217,11 +177,9 @@ public class AlphabeticalAppsList {
     /**
      * Sets the number of apps per row.
      */
-    public void setNumAppsPerRow(int numAppsPerRow, int numPredictedAppsPerRow,
-            MergeAlgorithm mergeAlgorithm) {
+    public void setNumAppsPerRow(int numAppsPerRow, int numPredictedAppsPerRow) {
         mNumAppsPerRow = numAppsPerRow;
         mNumPredictedAppsPerRow = numPredictedAppsPerRow;
-        mMergeAlgorithm = mergeAlgorithm;
 
         updateAdapterItems();
     }
@@ -241,13 +199,6 @@ public class AlphabeticalAppsList {
     }
 
     /**
-     * Returns sections of all the current filtered applications.
-     */
-    public List<SectionInfo> getSections() {
-        return mSections;
-    }
-
-    /**
      * Returns fast scroller sections of all the current filtered applications.
      */
     public List<FastScrollSectionInfo> getFastScrollerSections() {
@@ -403,7 +354,6 @@ public class AlphabeticalAppsList {
      * mCachedSectionNames to have been calculated for the set of all apps in mApps.
      */
     private void updateAdapterItems() {
-        SectionInfo lastSectionInfo = null;
         String lastSectionName = null;
         FastScrollSectionInfo lastFastScrollerSectionInfo = null;
         int position = 0;
@@ -413,7 +363,6 @@ public class AlphabeticalAppsList {
         mFilteredApps.clear();
         mFastScrollerSections.clear();
         mAdapterItems.clear();
-        mSections.clear();
 
         if (DEBUG_PREDICTIONS) {
             if (mPredictedAppComponents.isEmpty() && !mApps.isEmpty()) {
@@ -451,19 +400,14 @@ public class AlphabeticalAppsList {
 
             if (!mPredictedApps.isEmpty()) {
                 // Add a section for the predictions
-                lastSectionInfo = new SectionInfo();
                 lastFastScrollerSectionInfo = new FastScrollSectionInfo("");
-                AdapterItem sectionItem = AdapterItem.asSectionBreak(position++, lastSectionInfo);
-                mSections.add(lastSectionInfo);
                 mFastScrollerSections.add(lastFastScrollerSectionInfo);
-                mAdapterItems.add(sectionItem);
 
                 // Add the predicted app items
                 for (AppInfo info : mPredictedApps) {
-                    AdapterItem appItem = AdapterItem.asPredictedApp(position++, lastSectionInfo,
-                            "", lastSectionInfo.numApps++, info, appIndex++);
-                    if (lastSectionInfo.firstAppItem == null) {
-                        lastSectionInfo.firstAppItem = appItem;
+                    AdapterItem appItem = AdapterItem.asPredictedApp(position++, "", info,
+                            appIndex++);
+                    if (lastFastScrollerSectionInfo.fastScrollToItem == null) {
                         lastFastScrollerSectionInfo.fastScrollToItem = appItem;
                     }
                     mAdapterItems.add(appItem);
@@ -480,25 +424,15 @@ public class AlphabeticalAppsList {
             String sectionName = getAndUpdateCachedSectionName(info.title);
 
             // Create a new section if the section names do not match
-            if (lastSectionInfo == null || !sectionName.equals(lastSectionName)) {
+            if (!sectionName.equals(lastSectionName)) {
                 lastSectionName = sectionName;
-                lastSectionInfo = new SectionInfo();
                 lastFastScrollerSectionInfo = new FastScrollSectionInfo(sectionName);
-                mSections.add(lastSectionInfo);
                 mFastScrollerSections.add(lastFastScrollerSectionInfo);
-
-                // Create a new section item to break the flow of items in the list
-                if (!hasFilter()) {
-                    AdapterItem sectionItem = AdapterItem.asSectionBreak(position++, lastSectionInfo);
-                    mAdapterItems.add(sectionItem);
-                }
             }
 
             // Create an app item
-            AdapterItem appItem = AdapterItem.asApp(position++, lastSectionInfo, sectionName,
-                    lastSectionInfo.numApps++, info, appIndex++);
-            if (lastSectionInfo.firstAppItem == null) {
-                lastSectionInfo.firstAppItem = appItem;
+            AdapterItem appItem = AdapterItem.asApp(position++, sectionName, info, appIndex++);
+            if (lastFastScrollerSectionInfo.fastScrollToItem == null) {
                 lastFastScrollerSectionInfo.fastScrollToItem = appItem;
             }
             mAdapterItems.add(appItem);
@@ -515,9 +449,6 @@ public class AlphabeticalAppsList {
             mAdapterItems.add(AdapterItem.asMarketSearch(position++));
         }
 
-        // Merge multiple sections together as requested by the merge strategy for this device
-        mergeSections();
-
         if (mNumAppsPerRow != 0) {
             // Update the number of rows in the adapter after we do all the merging (otherwise, we
             // would have to shift the values again)
@@ -594,61 +525,6 @@ public class AlphabeticalAppsList {
     }
 
     /**
-     * Merges multiple sections to reduce visual raggedness.
-     */
-    private void mergeSections() {
-        // Ignore merging until we have an algorithm and a valid row size
-        if (mMergeAlgorithm == null || mNumAppsPerRow == 0) {
-            return;
-        }
-
-        // Go through each section and try and merge some of the sections
-        if (!hasFilter()) {
-            int sectionAppCount = 0;
-            for (int i = 0; i < mSections.size() - 1; i++) {
-                SectionInfo section = mSections.get(i);
-                sectionAppCount = section.numApps;
-                int mergeCount = 1;
-
-                // Merge rows based on the current strategy
-                while (i < (mSections.size() - 1) &&
-                        mMergeAlgorithm.continueMerging(section, mSections.get(i + 1),
-                                sectionAppCount, mNumAppsPerRow, mergeCount)) {
-                    SectionInfo nextSection = mSections.remove(i + 1);
-
-                    // Remove the next section break
-                    mAdapterItems.remove(nextSection.sectionBreakItem);
-                    int pos = mAdapterItems.indexOf(section.firstAppItem);
-
-                    // Point the section for these new apps to the merged section
-                    int nextPos = pos + section.numApps;
-                    for (int j = nextPos; j < (nextPos + nextSection.numApps); j++) {
-                        AdapterItem item = mAdapterItems.get(j);
-                        item.sectionInfo = section;
-                        item.sectionAppIndex += section.numApps;
-                    }
-
-                    // Update the following adapter items of the removed section item
-                    pos = mAdapterItems.indexOf(nextSection.firstAppItem);
-                    for (int j = pos; j < mAdapterItems.size(); j++) {
-                        AdapterItem item = mAdapterItems.get(j);
-                        item.position--;
-                    }
-                    section.numApps += nextSection.numApps;
-                    sectionAppCount += nextSection.numApps;
-
-                    if (DEBUG) {
-                        Log.d(TAG, "Merging: " + nextSection.firstAppItem.sectionName +
-                                " to " + section.firstAppItem.sectionName +
-                                " mergedNumRows: " + (sectionAppCount / mNumAppsPerRow));
-                    }
-                    mergeCount++;
-                }
-            }
-        }
-    }
-
-    /**
      * Returns the cached section name for the given title, recomputing and updating the cache if
      * the title has no cached section name.
      */
diff --git a/src/com/android/launcher3/widget/WidgetsListAdapter.java b/src/com/android/launcher3/widget/WidgetsListAdapter.java
index 6b8ea496e..ed0870811 100644
--- a/src/com/android/launcher3/widget/WidgetsListAdapter.java
+++ b/src/com/android/launcher3/widget/WidgetsListAdapter.java
@@ -27,12 +27,10 @@ import android.view.ViewGroup;
 import android.view.ViewGroup.LayoutParams;
 import android.widget.LinearLayout;
 
-import com.android.launcher3.BubbleTextView;
 import com.android.launcher3.LauncherAppState;
 import com.android.launcher3.R;
 import com.android.launcher3.Utilities;
 import com.android.launcher3.WidgetPreviewLoader;
-import com.android.launcher3.model.PackageItemInfo;
 import com.android.launcher3.model.WidgetItem;
 import com.android.launcher3.model.WidgetsModel;