Lazily binding folder pages and icons

Folders are bound before they are opened and unbound on close. This
allows us to recycle the views in folders

Bug: 139051851
Change-Id: Ic1ed3265c0f583af54d73dab6f2751bc95266ea9

res/layout/folder_application.xml

@@ -20,4 +20,5 @@
     style="@style/BaseIcon"
     android:textColor="?attr/folderTextColor"
     android:includeFontPadding="false"
+    android:hapticFeedbackEnabled="false"
     launcher:iconDisplay="folder" />

src/com/android/launcher3/FolderInfo.java

@@ -93,13 +93,6 @@ public class FolderInfo extends ItemInfo {
         itemsChanged(animate);
     }
 
-    public void setTitle(CharSequence title) {
-        this.title = title;
-        for (int i = 0; i < mListeners.size(); i++) {
-            mListeners.get(i).onTitleChanged(title);
-        }
-    }
-
     @Override
     public void onAddToDatabase(ContentWriter writer) {
         super.onAddToDatabase(writer);
@@ -121,18 +114,10 @@ public class FolderInfo extends ItemInfo {
         }
     }
 
-    public void prepareAutoUpdate() {
-        for (int i = 0; i < mListeners.size(); i++) {
-            mListeners.get(i).prepareAutoUpdate();
-        }
-    }
-
     public interface FolderListener {
         public void onAdd(WorkspaceItemInfo item, int rank);
         public void onRemove(WorkspaceItemInfo item);
-        public void onTitleChanged(CharSequence title);
         public void onItemsChanged(boolean animate);
-        public void prepareAutoUpdate();
     }
 
     public boolean hasOption(int optionFlag) {

src/com/android/launcher3/Launcher.java

@@ -2340,6 +2340,11 @@ public class Launcher extends BaseDraggingActivity implements LauncherExterns,
         // override the previous page so we don't log the page switch.
         mWorkspace.setCurrentPage(pageBoundFirst, pageBoundFirst /* overridePrevPage */);
 
+        // Cache one page worth of icons
+        getViewCache().setCacheSize(R.layout.folder_application,
+                mDeviceProfile.inv.numFolderColumns * mDeviceProfile.inv.numFolderRows);
+        getViewCache().setCacheSize(R.layout.folder_page, 2);
+
         TraceHelper.endSection("finishBindingItems");
     }
 

src/com/android/launcher3/Workspace.java

@@ -92,7 +92,6 @@ import com.android.launcher3.userevent.nano.LauncherLogProto.ContainerType;
 import com.android.launcher3.userevent.nano.LauncherLogProto.Target;
 import com.android.launcher3.util.Executors;
 import com.android.launcher3.util.IntArray;
-import com.android.launcher3.util.IntSet;
 import com.android.launcher3.util.IntSparseArrayMap;
 import com.android.launcher3.util.ItemInfoMatcher;
 import com.android.launcher3.util.PackageUserKey;
@@ -134,9 +133,6 @@ public class Workspace extends PagedView<WorkspacePageIndicator>
 
     private static final int DEFAULT_PAGE = 0;
 
-    public static final boolean MAP_NO_RECURSE = false;
-    public static final boolean MAP_RECURSE = true;
-
     private LayoutTransition mLayoutTransition;
     @Thunk final WallpaperManager mWallpaperManager;
 
@@ -2809,7 +2805,7 @@ public class Workspace extends PagedView<WorkspacePageIndicator>
      * Removes all folder listeners
      */
     public void removeFolderListeners() {
-        mapOverItems(false, new ItemOperator() {
+        mapOverItems(new ItemOperator() {
             @Override
             public boolean evaluate(ItemInfo info, View view) {
                 if (view instanceof FolderIcon) {
@@ -2961,7 +2957,7 @@ public class Workspace extends PagedView<WorkspacePageIndicator>
 
     public View getFirstMatch(final ItemOperator operator) {
         final View[] value = new View[1];
-        mapOverItems(MAP_NO_RECURSE, new ItemOperator() {
+        mapOverItems(new ItemOperator() {
             @Override
             public boolean evaluate(ItemInfo info, View v) {
                 if (operator.evaluate(info, v)) {
@@ -2984,7 +2980,7 @@ public class Workspace extends PagedView<WorkspacePageIndicator>
         final View[] matches = new View[operators.length];
         // For efficiency, the outer loop should be CellLayout.
         for (CellLayout cellLayout : cellLayouts) {
-            mapOverCellLayout(MAP_NO_RECURSE, cellLayout, (info, v) -> {
+            mapOverCellLayout(cellLayout, (info, v) -> {
                 for (int i = 0; i < operators.length; ++i) {
                     if (matches[i] == null && operators[i].evaluate(info, v)) {
                         matches[i] = v;
@@ -3009,7 +3005,7 @@ public class Workspace extends PagedView<WorkspacePageIndicator>
     }
 
     void clearDropTargets() {
-        mapOverItems(MAP_NO_RECURSE, new ItemOperator() {
+        mapOverItems(new ItemOperator() {
             @Override
             public boolean evaluate(ItemInfo info, View v) {
                 if (v instanceof DropTarget) {
@@ -3054,10 +3050,12 @@ public class Workspace extends PagedView<WorkspacePageIndicator>
                 } else if (itemToRemove.container >= 0) {
                     // The item may belong to a folder.
                     View parent = idToViewMap.get(itemToRemove.container);
-                    if (parent != null) {
+                    if (parent instanceof FolderIcon) {
                         FolderInfo folderInfo = (FolderInfo) parent.getTag();
-                        folderInfo.prepareAutoUpdate();
                         folderInfo.remove((WorkspaceItemInfo) itemToRemove, false);
+                        if (((FolderIcon) parent).getFolder().isOpen()) {
+                            ((FolderIcon) parent).getFolder().close(false /* animate */);
+                        }
                     }
                 }
             }
@@ -3081,18 +3079,17 @@ public class Workspace extends PagedView<WorkspacePageIndicator>
     /**
      * Map the operator over the shortcuts and widgets, return the first-non-null value.
      *
-     * @param recurse true: iterate over folder children. false: op get the folders themselves.
      * @param op the operator to map over the shortcuts
      */
-    public void mapOverItems(boolean recurse, ItemOperator op) {
+    public void mapOverItems(ItemOperator op) {
         for (CellLayout layout : getWorkspaceAndHotseatCellLayouts()) {
-            if (mapOverCellLayout(recurse, layout, op)) {
+            if (mapOverCellLayout(layout, op)) {
                 return;
             }
         }
     }
 
-    private boolean mapOverCellLayout(boolean recurse, CellLayout layout, ItemOperator op) {
+    private boolean mapOverCellLayout(CellLayout layout, ItemOperator op) {
         // TODO(b/128460496) Potential race condition where layout is not yet loaded
         if (layout == null) {
             return false;
@@ -3102,103 +3099,68 @@ public class Workspace extends PagedView<WorkspacePageIndicator>
         final int itemCount = container.getChildCount();
         for (int itemIdx = 0; itemIdx < itemCount; itemIdx++) {
             View item = container.getChildAt(itemIdx);
-            ItemInfo info = (ItemInfo) item.getTag();
+            if (op.evaluate((ItemInfo) item.getTag(), item)) {
-            if (recurse && info instanceof FolderInfo && item instanceof FolderIcon) {
-                FolderIcon folder = (FolderIcon) item;
-                ArrayList<View> folderChildren = folder.getFolder().getIconsInReadingOrder();
-                // map over all the children in the folder
-                final int childCount = folderChildren.size();
-                for (int childIdx = 0; childIdx < childCount; childIdx++) {
-                    View child = folderChildren.get(childIdx);
-                    info = (ItemInfo) child.getTag();
-                    if (op.evaluate(info, child)) {
                 return true;
             }
         }
-            } else {
-                if (op.evaluate(info, item)) {
-                    return true;
-                }
-            }
-        }
         return false;
     }
 
     void updateShortcuts(ArrayList<WorkspaceItemInfo> shortcuts) {
-        int total  = shortcuts.size();
+        final HashSet<WorkspaceItemInfo> updates = new HashSet<>(shortcuts);
-        final HashSet<WorkspaceItemInfo> updates = new HashSet<>(total);
+        ItemOperator op = (info, v) -> {
-        final IntSet folderIds = new IntSet();
+            if (v instanceof BubbleTextView && updates.contains(info)) {
-
-        for (int i = 0; i < total; i++) {
-            WorkspaceItemInfo s = shortcuts.get(i);
-            updates.add(s);
-            folderIds.add(s.container);
-        }
-
-        mapOverItems(MAP_RECURSE, new ItemOperator() {
-            @Override
-            public boolean evaluate(ItemInfo info, View v) {
-                if (info instanceof WorkspaceItemInfo && v instanceof BubbleTextView &&
-                        updates.contains(info)) {
                 WorkspaceItemInfo si = (WorkspaceItemInfo) info;
                 BubbleTextView shortcut = (BubbleTextView) v;
                 Drawable oldIcon = shortcut.getIcon();
                 boolean oldPromiseState = (oldIcon instanceof PreloadIconDrawable)
                         && ((PreloadIconDrawable) oldIcon).hasNotCompleted();
                 shortcut.applyFromWorkspaceItem(si, si.isPromise() != oldPromiseState);
+            } else if (info instanceof FolderInfo && v instanceof FolderIcon) {
+                ((FolderIcon) v).updatePreviewItems(updates::contains);
             }
-                // process all the shortcuts
-                return false;
-            }
-        });
 
-        // Update folder icons
+            // Iterate all items
-        mapOverItems(MAP_NO_RECURSE, new ItemOperator() {
-            @Override
-            public boolean evaluate(ItemInfo info, View v) {
-                if (info instanceof FolderInfo && folderIds.contains(info.id)) {
-                    ((FolderInfo) info).itemsChanged(false);
-                }
-                // process all the shortcuts
             return false;
+        };
+
+        mapOverItems(op);
+        Folder openFolder = Folder.getOpen(mLauncher);
+        if (openFolder != null) {
+            openFolder.iterateOverItems(op);
         }
-        });
     }
 
     public void updateNotificationDots(Predicate<PackageUserKey> updatedDots) {
         final PackageUserKey packageUserKey = new PackageUserKey(null, null);
-        final IntSet folderIds = new IntSet();
+        Predicate<ItemInfo> matcher = info -> !packageUserKey.updateFromItemInfo(info)
-        mapOverItems(MAP_RECURSE, new ItemOperator() {
+                || updatedDots.test(packageUserKey);
-            @Override
-            public boolean evaluate(ItemInfo info, View v) {
-                if (info instanceof WorkspaceItemInfo && v instanceof BubbleTextView) {
-                    if (!packageUserKey.updateFromItemInfo(info)
-                            || updatedDots.test(packageUserKey)) {
-                        ((BubbleTextView) v).applyDotState(info, true /* animate */);
-                        folderIds.add(info.container);
-                    }
-                }
-                // process all the shortcuts
-                return false;
-            }
-        });
 
-        // Update folder icons
+        ItemOperator op = (info, v) -> {
-        mapOverItems(MAP_NO_RECURSE, new ItemOperator() {
+            if (info instanceof WorkspaceItemInfo && v instanceof BubbleTextView) {
-            @Override
+                if (matcher.test(info)) {
-            public boolean evaluate(ItemInfo info, View v) {
+                    ((BubbleTextView) v).applyDotState(info, true /* animate */);
-                if (info instanceof FolderInfo && folderIds.contains(info.id)
+                }
-                        && v instanceof FolderIcon) {
+            } else if (info instanceof FolderInfo && v instanceof FolderIcon) {
+                FolderInfo fi = (FolderInfo) info;
+                if (fi.contents.stream().anyMatch(matcher)) {
                     FolderDotInfo folderDotInfo = new FolderDotInfo();
-                    for (WorkspaceItemInfo si : ((FolderInfo) info).contents) {
+                    for (WorkspaceItemInfo si : fi.contents) {
                         folderDotInfo.addDotInfo(mLauncher.getDotInfoForItem(si));
                     }
                     ((FolderIcon) v).setDotInfo(folderDotInfo);
                 }
+            }
+
             // process all the shortcuts
             return false;
+        };
+
+        mapOverItems(op);
+        Folder folder = Folder.getOpen(mLauncher);
+        if (folder != null) {
+            folder.iterateOverItems(op);
         }
-        });
     }
 
     public void removeAbandonedPromise(String packageName, UserHandle user) {
@@ -3210,9 +3172,7 @@ public class Workspace extends PagedView<WorkspacePageIndicator>
     }
 
     public void updateRestoreItems(final HashSet<ItemInfo> updates) {
-        mapOverItems(MAP_RECURSE, new ItemOperator() {
+        ItemOperator op = (info, v) -> {
-            @Override
-            public boolean evaluate(ItemInfo info, View v) {
             if (info instanceof WorkspaceItemInfo && v instanceof BubbleTextView
                     && updates.contains(info)) {
                 ((BubbleTextView) v).applyPromiseState(false /* promiseStateChanged */);
@@ -3220,11 +3180,17 @@ public class Workspace extends PagedView<WorkspacePageIndicator>
                     && info instanceof LauncherAppWidgetInfo
                     && updates.contains(info)) {
                 ((PendingAppWidgetHostView) v).applyState();
+            } else if (v instanceof FolderIcon && info instanceof FolderInfo) {
+                ((FolderIcon) v).updatePreviewItems(updates::contains);
             }
             // process all the shortcuts
             return false;
+        };
+        mapOverItems(op);
+        Folder folder = Folder.getOpen(mLauncher);
+        if (folder != null) {
+            folder.iterateOverItems(op);
         }
-        });
     }
 
     public void widgetsRestored(final ArrayList<LauncherAppWidgetInfo> changedInfo) {
@@ -3248,7 +3214,7 @@ public class Workspace extends PagedView<WorkspacePageIndicator>
             } else {
                 // widgetRefresh will automatically run when the packages are updated.
                 // For now just update the progress bars
-                mapOverItems(MAP_NO_RECURSE, new ItemOperator() {
+                mapOverItems(new ItemOperator() {
                     @Override
                     public boolean evaluate(ItemInfo info, View view) {
                         if (view instanceof PendingAppWidgetHostView
@@ -3372,7 +3338,7 @@ public class Workspace extends PagedView<WorkspacePageIndicator>
             mRefreshPending = false;
 
             ArrayList<PendingAppWidgetHostView> views = new ArrayList<>(mInfos.size());
-            mapOverItems(MAP_NO_RECURSE, (info, view) -> {
+            mapOverItems((info, view) -> {
                 if (view instanceof PendingAppWidgetHostView && mInfos.contains(info)) {
                     views.add((PendingAppWidgetHostView) view);
                 }

src/com/android/launcher3/folder/Folder.java

@@ -170,8 +170,6 @@ public class Folder extends AbstractFloatingView implements ClipPathView, DragSo
     private boolean mDeleteFolderOnDropCompleted = false;
     private boolean mSuppressFolderDeletion = false;
     private boolean mItemAddedBackToSelfViaIcon = false;
-    @Thunk float mFolderIconPivotX;
-    @Thunk float mFolderIconPivotY;
     private boolean mIsEditingName = false;
 
     @ViewDebug.ExportedProperty(category = "launcher")
@@ -310,7 +308,8 @@ public class Folder extends AbstractFloatingView implements ClipPathView, DragSo
         // Convert to a string here to ensure that no other state associated with the text field
         // gets saved.
         String newTitle = mFolderName.getText().toString();
-        mInfo.setTitle(newTitle);
+        mInfo.title = newTitle;
+        mFolderIcon.onTitleChanged(newTitle);
         mLauncher.getModelWriter().updateItemInDatabase(mInfo);
 
         if (TextUtils.isEmpty(mInfo.title)) {
@@ -385,7 +384,6 @@ public class Folder extends AbstractFloatingView implements ClipPathView, DragSo
         ArrayList<WorkspaceItemInfo> children = info.contents;
         Collections.sort(children, ITEM_POS_COMPARATOR);
         updateItemLocationsInDatabaseBatch();
-        mContent.bindItems(children);
 
         DragLayer.LayoutParams lp = (DragLayer.LayoutParams) getLayoutParams();
         if (lp == null) {
@@ -393,13 +391,10 @@ public class Folder extends AbstractFloatingView implements ClipPathView, DragSo
             lp.customPosition = true;
             setLayoutParams(lp);
         }
-        centerAboutIcon();
-
         mItemsInvalidated = true;
-        updateTextViewFocus();
         mInfo.addListener(this);
 
-        if (TextUtils.isEmpty(mInfo.title)) {
+        if (!TextUtils.isEmpty(mInfo.title)) {
             mFolderName.setText(mInfo.title);
             mFolderName.setHint(null);
         } else {
@@ -408,12 +403,10 @@ public class Folder extends AbstractFloatingView implements ClipPathView, DragSo
         }
 
         // In case any children didn't come across during loading, clean up the folder accordingly
-        mFolderIcon.post(new Runnable() {
+        mFolderIcon.post(() -> {
-            public void run() {
             if (getItemCount() <= 1) {
                 replaceFolderWithFinalItem();
             }
-            }
         });
     }
 
@@ -472,18 +465,50 @@ public class Folder extends AbstractFloatingView implements ClipPathView, DragSo
         return folderCount >= MIN_FOLDERS_FOR_HARDWARE_OPTIMIZATION;
     }
 
+    /**
+     * Opens the folder as part of a drag operation
+     */
+    public void beginExternalDrag() {
+        mIsExternalDrag = true;
+        mDragInProgress = true;
+
+        // Since this folder opened by another controller, it might not get onDrop or
+        // onDropComplete. Perform cleanup once drag-n-drop ends.
+        mDragController.addDragListener(this);
+
+        ArrayList<WorkspaceItemInfo> items = new ArrayList<>(mInfo.contents);
+        mEmptyCellRank = items.size();
+        items.add(null);    // Add an empty spot at the end
+
+        animateOpen(items, mEmptyCellRank / mContent.itemsPerPage());
+    }
+
     /**
      * Opens the user folder described by the specified tag. The opening of the folder
      * is animated relative to the specified View. If the View is null, no animation
      * is played.
      */
     public void animateOpen() {
+        animateOpen(mInfo.contents, 0);
+    }
+
+    /**
+     * Opens the user folder described by the specified tag. The opening of the folder
+     * is animated relative to the specified View. If the View is null, no animation
+     * is played.
+     */
+    private void animateOpen(List<WorkspaceItemInfo> items, int pageNo) {
         Folder openFolder = getOpen(mLauncher);
         if (openFolder != null && openFolder != this) {
             // Close any open folder before opening a folder.
             openFolder.close(true);
         }
 
+        mContent.bindItems(items);
+        centerAboutIcon();
+        mItemsInvalidated = true;
+        updateTextViewFocus();
+
         mIsOpen = true;
 
         DragLayer dragLayer = mLauncher.getDragLayer();
@@ -500,10 +525,7 @@ public class Folder extends AbstractFloatingView implements ClipPathView, DragSo
         }
 
         mContent.completePendingPageChanges();
-        if (!mDragInProgress) {
+        mContent.snapToPageImmediately(pageNo);
-            // Open on the first page.
-            mContent.snapToPageImmediately(0);
-        }
 
         // This is set to true in close(), but isn't reset to false until onDropCompleted(). This
         // leads to an inconsistent state if you drag out of the folder and drag back in without
@@ -574,16 +596,6 @@ public class Folder extends AbstractFloatingView implements ClipPathView, DragSo
         mContent.verifyVisibleHighResIcons(mContent.getNextPage());
     }
 
-    public void beginExternalDrag() {
-        mEmptyCellRank = mContent.allocateRankForNewItem();
-        mIsExternalDrag = true;
-        mDragInProgress = true;
-
-        // Since this folder opened by another controller, it might not get onDrop or
-        // onDropComplete. Perform cleanup once drag-n-drop ends.
-        mDragController.addDragListener(this);
-    }
-
     @Override
     protected boolean isOfType(int type) {
         return (type & TYPE_FOLDER) != 0;
@@ -668,6 +680,8 @@ public class Folder extends AbstractFloatingView implements ClipPathView, DragSo
             } else if (mDragInProgress) {
                 mDeleteFolderOnDropCompleted = true;
             }
+        } else if (!mDragInProgress) {
+            mContent.unbindItems();
         }
         mSuppressFolderDeletion = false;
         clearDragInfo();
@@ -953,24 +967,12 @@ public class Folder extends AbstractFloatingView implements ClipPathView, DragSo
         setPivotX(folderPivotX);
         setPivotY(folderPivotY);
 
-        mFolderIconPivotX = (int) (mFolderIcon.getMeasuredWidth() *
-                (1.0f * folderPivotX / width));
-        mFolderIconPivotY = (int) (mFolderIcon.getMeasuredHeight() *
-                (1.0f * folderPivotY / height));
-
         lp.width = width;
         lp.height = height;
         lp.x = left;
         lp.y = top;
     }
 
-    public float getPivotXForIconAnimation() {
-        return mFolderIconPivotX;
-    }
-    public float getPivotYForIconAnimation() {
-        return mFolderIconPivotY;
-    }
-
     private int getContentAreaHeight() {
         DeviceProfile grid = mLauncher.getDeviceProfile();
         int maxContentAreaHeight = grid.availableHeightPx
@@ -1031,7 +1033,7 @@ public class Folder extends AbstractFloatingView implements ClipPathView, DragSo
     }
 
     public int getItemCount() {
-        return mContent.getItemCount();
+        return mInfo.contents.size();
     }
 
     @Thunk void replaceFolderWithFinalItem() {
@@ -1039,7 +1041,7 @@ public class Folder extends AbstractFloatingView implements ClipPathView, DragSo
         Runnable onCompleteRunnable = new Runnable() {
             @Override
             public void run() {
-                int itemCount = mInfo.contents.size();
+                int itemCount = getItemCount();
                 if (itemCount <= 1) {
                     View newIcon = null;
 
@@ -1116,6 +1118,8 @@ public class Folder extends AbstractFloatingView implements ClipPathView, DragSo
                     return false;
                 }
             });
+        } else {
+            setOnKeyListener(null);
         }
     }
 
@@ -1242,9 +1246,9 @@ public class Folder extends AbstractFloatingView implements ClipPathView, DragSo
                 item.cellY);
         updateItemLocationsInDatabaseBatch();
 
-        ArrayList<View> items = new ArrayList<>(getIconsInReadingOrder());
+        if (mContent.areViewsBound()) {
-        items.add(rank, mContent.createAndAddViewForRank(item, rank));
+            mContent.createAndAddViewForRank(item, rank);
-        mContent.arrangeChildren(items);
+        }
         mItemsInvalidated = true;
     }
 
@@ -1275,12 +1279,11 @@ public class Folder extends AbstractFloatingView implements ClipPathView, DragSo
         updateTextViewFocus();
     }
 
-    @Override
+    /**
-    public void prepareAutoUpdate() {
+     * Utility methods to iterate over items of the view
-        close(false);
+     */
-    }
+    public void iterateOverItems(ItemOperator op) {
-
+        mContent.iterateOverItems(op);
-    public void onTitleChanged(CharSequence title) {
     }
 
     /**
@@ -1289,14 +1292,7 @@ public class Folder extends AbstractFloatingView implements ClipPathView, DragSo
     public ArrayList<View> getIconsInReadingOrder() {
         if (mItemsInvalidated) {
             mItemsInReadingOrder.clear();
-            mContent.iterateOverItems(new ItemOperator() {
+            mContent.iterateOverItems((i, v) -> !mItemsInReadingOrder.add(v));
-
-                @Override
-                public boolean evaluate(ItemInfo info, View view) {
-                    mItemsInReadingOrder.add(view);
-                    return false;
-                }
-            });
             mItemsInvalidated = false;
         }
         return mItemsInReadingOrder;

src/com/android/launcher3/folder/FolderIcon.java

@@ -69,6 +69,7 @@ import com.android.launcher3.widget.PendingAddShortcutInfo;
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.function.Predicate;
 
 /**
  * An icon that can appear on in the workspace representing an {@link Folder}.
@@ -99,7 +100,7 @@ public class FolderIcon extends FrameLayout implements FolderListener {
     ClippedFolderIconLayoutRule mPreviewLayoutRule;
     private PreviewItemManager mPreviewItemManager;
     private PreviewItemDrawingParams mTmpParams = new PreviewItemDrawingParams(0, 0, 0, 0);
-    private List<BubbleTextView> mCurrentPreviewItems = new ArrayList<>();
+    private List<WorkspaceItemInfo> mCurrentPreviewItems = new ArrayList<>();
 
     boolean mAnimating = false;
 
@@ -255,7 +256,6 @@ public class FolderIcon extends FrameLayout implements FolderListener {
     OnAlarmListener mOnOpenListener = new OnAlarmListener() {
         public void onAlarm(Alarm alarm) {
             mFolder.beginExternalDrag();
-            mFolder.animateOpen();
         }
     };
 
@@ -321,18 +321,17 @@ public class FolderIcon extends FrameLayout implements FolderListener {
             int numItemsInPreview = Math.min(MAX_NUM_ITEMS_IN_PREVIEW, index + 1);
             boolean itemAdded = false;
             if (itemReturnedOnFailedDrop || index >= MAX_NUM_ITEMS_IN_PREVIEW) {
-                List<BubbleTextView> oldPreviewItems = new ArrayList<>(mCurrentPreviewItems);
+                List<WorkspaceItemInfo> oldPreviewItems = new ArrayList<>(mCurrentPreviewItems);
                 mInfo.add(item, index, false);
                 mCurrentPreviewItems.clear();
-                mCurrentPreviewItems.addAll(getPreviewIconsOnPage(0));
+                mCurrentPreviewItems.addAll(getPreviewItemsOnPage(0));
 
                 if (!oldPreviewItems.equals(mCurrentPreviewItems)) {
-                    for (int i = 0; i < mCurrentPreviewItems.size(); ++i) {
+                    int newIndex = mCurrentPreviewItems.indexOf(item);
-                        if (mCurrentPreviewItems.get(i).getTag().equals(item)) {
+                    if (newIndex >= 0) {
                         // If the item dropped is going to be in the preview, we update the
                         // index here to reflect its position in the preview.
-                            index = i;
+                        index = newIndex;
-                        }
                     }
 
                     mPreviewItemManager.hidePreviewItem(index, true);
@@ -531,11 +530,10 @@ public class FolderIcon extends FrameLayout implements FolderListener {
     }
 
     /**
-     * Returns the list of "preview items" on {@param page}.
+     * Returns the list of items which should be visible in the preview
      */
-    public List<BubbleTextView> getPreviewIconsOnPage(int page) {
+    public List<WorkspaceItemInfo> getPreviewItemsOnPage(int page) {
-        return mPreviewVerifier.setFolderInfo(mFolder.mInfo)
+        return mPreviewVerifier.setFolderInfo(mInfo).previewItemsForPage(page, mInfo.contents);
-                .previewItemsForPage(page, mFolder.getIconsInReadingOrder());
     }
 
     @Override
@@ -553,11 +551,14 @@ public class FolderIcon extends FrameLayout implements FolderListener {
     private void updatePreviewItems(boolean animate) {
         mPreviewItemManager.updatePreviewItems(animate);
         mCurrentPreviewItems.clear();
-        mCurrentPreviewItems.addAll(getPreviewIconsOnPage(0));
+        mCurrentPreviewItems.addAll(getPreviewItemsOnPage(0));
     }
 
-    @Override
+    /**
-    public void prepareAutoUpdate() {
+     * Updates the preview items which match the provided condition
+     */
+    public void updatePreviewItems(Predicate<WorkspaceItemInfo> itemCheck) {
+        mPreviewItemManager.updatePreviewItems(itemCheck);
     }
 
     @Override
@@ -580,7 +581,6 @@ public class FolderIcon extends FrameLayout implements FolderListener {
         requestLayout();
     }
 
-    @Override
     public void onTitleChanged(CharSequence title) {
         mFolderName.setText(title);
         setContentDescription(getContext().getString(R.string.folder_name_format, title));

src/com/android/launcher3/folder/FolderPagedView.java

@@ -24,10 +24,10 @@ import android.util.ArrayMap;
 import android.util.AttributeSet;
 import android.util.Log;
 import android.view.Gravity;
-import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewDebug;
 
+import com.android.launcher3.BaseActivity;
 import com.android.launcher3.BubbleTextView;
 import com.android.launcher3.CellLayout;
 import com.android.launcher3.DeviceProfile;
@@ -46,11 +46,14 @@ import com.android.launcher3.keyboard.ViewGroupFocusHelper;
 import com.android.launcher3.pageindicators.PageIndicatorDots;
 import com.android.launcher3.touch.ItemClickHandler;
 import com.android.launcher3.util.Thunk;
+import com.android.launcher3.util.ViewCache;
 
 import java.util.ArrayList;
 import java.util.Iterator;
+import java.util.List;
 import java.util.Map;
 import java.util.function.ToIntFunction;
+import java.util.stream.Collectors;
 
 public class FolderPagedView extends PagedView<PageIndicatorDots> {
 
@@ -69,12 +72,12 @@ public class FolderPagedView extends PagedView<PageIndicatorDots> {
 
     public final boolean mIsRtl;
 
-    private final LayoutInflater mInflater;
     private final ViewGroupFocusHelper mFocusIndicatorHelper;
 
     @Thunk final ArrayMap<View, Runnable> mPendingAnimations = new ArrayMap<>();
 
     private final FolderGridOrganizer mOrganizer;
+    private final ViewCache mViewCache;
 
     private int mAllocatedContentSize;
     @ViewDebug.ExportedProperty(category = "launcher")
@@ -84,17 +87,20 @@ public class FolderPagedView extends PagedView<PageIndicatorDots> {
 
     private Folder mFolder;
 
+    // If the views are attached to the folder or not. A folder should be bound when its
+    // animating or is open.
+    private boolean mViewsBound = false;
+
     public FolderPagedView(Context context, AttributeSet attrs) {
         super(context, attrs);
         InvariantDeviceProfile profile = LauncherAppState.getIDP(context);
         mOrganizer = new FolderGridOrganizer(profile);
 
-        mInflater = LayoutInflater.from(context);
-
         mIsRtl = Utilities.isRtl(getResources());
         setImportantForAccessibility(IMPORTANT_FOR_ACCESSIBILITY_YES);
 
         mFocusIndicatorHelper = new ViewGroupFocusHelper(this);
+        mViewCache = BaseActivity.fromContext(context).getViewCache();
     }
 
     public void setFolder(Folder folder) {
@@ -127,35 +133,50 @@ public class FolderPagedView extends PagedView<PageIndicatorDots> {
     /**
      * Binds items to the layout.
      */
-    public void bindItems(ArrayList<WorkspaceItemInfo> items) {
+    public void bindItems(List<WorkspaceItemInfo> items) {
-        ArrayList<View> icons = new ArrayList<>();
+        if (mViewsBound) {
-        for (WorkspaceItemInfo item : items) {
+            unbindItems();
-            icons.add(createNewView(item));
         }
-        arrangeChildren(icons);
+        arrangeChildren(items.stream().map(this::createNewView).collect(Collectors.toList()));
-    }
+        mViewsBound = true;
-
-    public void allocateSpaceForRank(int rank) {
-        ArrayList<View> views = new ArrayList<>(mFolder.getIconsInReadingOrder());
-        views.add(rank, null);
-        arrangeChildren(views);
     }
 
     /**
-     * Create space for a new item at the end, and returns the rank for that item.
+     * Removes all the icons from the folder
-     * Also sets the current page to the last page.
      */
-    public int allocateRankForNewItem() {
+    public void unbindItems() {
-        int rank = getItemCount();
+        for (int i = getChildCount() - 1; i >= 0; i--) {
-        allocateSpaceForRank(rank);
+            CellLayout page = (CellLayout) getChildAt(i);
-        setCurrentPage(rank / mOrganizer.getMaxItemsPerPage());
+            ShortcutAndWidgetContainer container = page.getShortcutsAndWidgets();
-        return rank;
+            for (int j = container.getChildCount() - 1; j >= 0; j--) {
+                mViewCache.recycleView(R.layout.folder_application, container.getChildAt(j));
+            }
+            page.removeAllViews();
+            mViewCache.recycleView(R.layout.folder_page, page);
+        }
+        removeAllViews();
+        mViewsBound = false;
     }
 
+    /**
+     * Returns true if the icons are bound to the folder
+     */
+    public boolean areViewsBound() {
+        return mViewsBound;
+    }
+
+    /**
+     * Creates and adds an icon corresponding to the provided rank
+     * @return the created icon
+     */
     public View createAndAddViewForRank(WorkspaceItemInfo item, int rank) {
         View icon = createNewView(item);
-        allocateSpaceForRank(rank);
+        if (!mViewsBound) {
-        addViewForRank(icon, item, rank);
+            return icon;
+        }
+        ArrayList<View> views = new ArrayList<>(mFolder.getIconsInReadingOrder());
+        views.add(rank, icon);
+        arrangeChildren(views);
         return icon;
     }
 
@@ -173,16 +194,24 @@ public class FolderPagedView extends PagedView<PageIndicatorDots> {
 
     @SuppressLint("InflateParams")
     public View createNewView(WorkspaceItemInfo item) {
-        final BubbleTextView textView = (BubbleTextView) mInflater.inflate(
+        if (item == null) {
-                R.layout.folder_application, null, false);
+            return null;
+        }
+        final BubbleTextView textView = mViewCache.getView(
+                R.layout.folder_application, getContext(), null);
         textView.applyFromWorkspaceItem(item);
-        textView.setHapticFeedbackEnabled(false);
         textView.setOnClickListener(ItemClickHandler.INSTANCE);
         textView.setOnLongClickListener(mFolder);
         textView.setOnFocusChangeListener(mFocusIndicatorHelper);
-
+        CellLayout.LayoutParams lp = (CellLayout.LayoutParams) textView.getLayoutParams();
+        if (lp == null) {
             textView.setLayoutParams(new CellLayout.LayoutParams(
                     item.cellX, item.cellY, item.spanX, item.spanY));
+        } else {
+            lp.cellX = item.cellX;
+            lp.cellY = item.cellY;
+            lp.cellHSpan = lp.cellVSpan = 1;
+        }
         return textView;
     }
 
@@ -197,7 +226,7 @@ public class FolderPagedView extends PagedView<PageIndicatorDots> {
 
     private CellLayout createAndAddNewPage() {
         DeviceProfile grid = Launcher.getLauncher(getContext()).getDeviceProfile();
-        CellLayout page = (CellLayout) mInflater.inflate(R.layout.folder_page, this, false);
+        CellLayout page = mViewCache.getView(R.layout.folder_page, getContext(), this);
         page.setCellDimensions(grid.folderCellWidthPx, grid.folderCellHeightPx);
         page.getShortcutsAndWidgets().setMotionEventSplittingEnabled(false);
         page.setInvertIfRtl(true);
@@ -240,7 +269,7 @@ public class FolderPagedView extends PagedView<PageIndicatorDots> {
      * @param list the ordered list of children.
      */
     @SuppressLint("RtlHardcoded")
-    public void arrangeChildren(ArrayList<View> list) {
+    public void arrangeChildren(List<View> list) {
         int itemCount = list.size();
         ArrayList<CellLayout> pages = new ArrayList<>();
         for (int i = 0; i < getChildCount(); i++) {
@@ -313,16 +342,6 @@ public class FolderPagedView extends PagedView<PageIndicatorDots> {
                 (getPageAt(0).getDesiredHeight() + getPaddingTop() + getPaddingBottom()) : 0;
     }
 
-    public int getItemCount() {
-        int lastPageIndex = getChildCount() - 1;
-        if (lastPageIndex < 0) {
-            // If there are no pages, nothing has yet been added to the folder.
-            return 0;
-        }
-        return getPageAt(lastPageIndex).getShortcutsAndWidgets().getChildCount()
-                + lastPageIndex * mOrganizer.getMaxItemsPerPage();
-    }
-
     /**
      * @return the rank of the cell nearest to the provided pixel position.
      */

src/com/android/launcher3/folder/PreviewItemDrawingParams.java

@@ -17,6 +17,8 @@ package com.android.launcher3.folder;
 
 import android.graphics.drawable.Drawable;
 
+import com.android.launcher3.WorkspaceItemInfo;
+
 /**
  * Manages the parameters used to draw a Folder preview item.
  */
@@ -25,9 +27,10 @@ class PreviewItemDrawingParams {
     float transY;
     float scale;
     float overlayAlpha;
-    FolderPreviewItemAnim anim;
+    public FolderPreviewItemAnim anim;
     public boolean hidden;
-    Drawable drawable;
+    public Drawable drawable;
+    public WorkspaceItemInfo item;
 
     PreviewItemDrawingParams(float transX, float transY, float scale, float overlayAlpha) {
         this.transX = transX;

src/com/android/launcher3/folder/PreviewItemManager.java

@@ -23,28 +23,51 @@ import static com.android.launcher3.folder.FolderIcon.DROP_IN_ANIMATION_DURATION
 
 import android.animation.Animator;
 import android.animation.AnimatorListenerAdapter;
+import android.animation.ObjectAnimator;
 import android.animation.ValueAnimator;
+import android.content.Context;
 import android.graphics.Canvas;
 import android.graphics.Rect;
 import android.graphics.drawable.Drawable;
+import android.util.FloatProperty;
 import android.view.View;
 import android.widget.TextView;
 
 import androidx.annotation.NonNull;
 
-import com.android.launcher3.BubbleTextView;
+import com.android.launcher3.Launcher;
 import com.android.launcher3.Utilities;
 import com.android.launcher3.WorkspaceItemInfo;
+import com.android.launcher3.graphics.DrawableFactory;
+import com.android.launcher3.graphics.PreloadIconDrawable;
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.function.Predicate;
 
 /**
  * Manages the drawing and animations of {@link PreviewItemDrawingParams} for a {@link FolderIcon}.
  */
 public class PreviewItemManager {
 
-    private FolderIcon mIcon;
+    private static final FloatProperty<PreviewItemManager> CURRENT_PAGE_ITEMS_TRANS_X =
+            new FloatProperty<PreviewItemManager>("currentPageItemsTransX") {
+                @Override
+                public void setValue(PreviewItemManager manager, float v) {
+                    manager.mCurrentPageItemsTransX = v;
+                    manager.onParamsChanged();
+                }
+
+                @Override
+                public Float get(PreviewItemManager manager) {
+                    return manager.mCurrentPageItemsTransX;
+                }
+            };
+
+    private final Context mContext;
+    private final FolderIcon mIcon;
+    private final DrawableFactory mDrawableFactory;
+    private final int mIconSize;
 
     // These variables are all associated with the drawing of the preview; they are stored
     // as member variables for shared usage and to avoid computation on each frame
@@ -69,7 +92,10 @@ public class PreviewItemManager {
     private static final int ITEM_SLIDE_IN_OUT_DISTANCE_PX = 200;
 
     public PreviewItemManager(FolderIcon icon) {
+        mContext = icon.getContext();
         mIcon = icon;
+        mDrawableFactory = DrawableFactory.INSTANCE.get(mContext);
+        mIconSize = Launcher.getLauncher(mContext).getDeviceProfile().folderChildIconSizePx;
     }
 
     /**
@@ -200,7 +226,7 @@ public class PreviewItemManager {
     }
 
     void buildParamsForPage(int page, ArrayList<PreviewItemDrawingParams> params, boolean animate) {
-        List<BubbleTextView> items = mIcon.getPreviewIconsOnPage(page);
+        List<WorkspaceItemInfo> items = mIcon.getPreviewItemsOnPage(page);
         int prevNumItems = params.size();
 
         // We adjust the size of the list to match the number of items in the preview.
@@ -214,13 +240,7 @@ public class PreviewItemManager {
         int numItemsInFirstPagePreview = page == 0 ? items.size() : MAX_NUM_ITEMS_IN_PREVIEW;
         for (int i = 0; i < params.size(); i++) {
             PreviewItemDrawingParams p = params.get(i);
-            p.drawable = items.get(i).getCompoundDrawables()[1];
+            setDrawable(p, items.get(i));
-
-            if (p.drawable != null && !mIcon.mFolder.isOpen()) {
-                // Set the callback to FolderIcon as it is responsible to drawing the icon. The
-                // callback will be released when the folder is opened.
-                p.drawable.setCallback(mIcon);
-            }
 
             if (!animate) {
                 computePreviewItemDrawingParams(i, numItemsInFirstPagePreview, p);
@@ -253,14 +273,8 @@ public class PreviewItemManager {
             buildParamsForPage(currentPage, mCurrentPageParams, false);
             onParamsChanged();
 
-            ValueAnimator slideAnimator = ValueAnimator.ofFloat(0, ITEM_SLIDE_IN_OUT_DISTANCE_PX);
+            ValueAnimator slideAnimator = ObjectAnimator
-            slideAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
+                    .ofFloat(this, CURRENT_PAGE_ITEMS_TRANS_X, 0, ITEM_SLIDE_IN_OUT_DISTANCE_PX);
-                @Override
-                public void onAnimationUpdate(ValueAnimator valueAnimator) {
-                    mCurrentPageItemsTransX = (float) valueAnimator.getAnimatedValue();
-                    onParamsChanged();
-                }
-            });
             slideAnimator.addListener(new AnimatorListenerAdapter() {
                 @Override
                 public void onAnimationEnd(Animator animation) {
@@ -277,6 +291,25 @@ public class PreviewItemManager {
         buildParamsForPage(0, mFirstPageParams, animate);
     }
 
+    void updatePreviewItems(Predicate<WorkspaceItemInfo> itemCheck) {
+        boolean modified = false;
+        for (PreviewItemDrawingParams param : mFirstPageParams) {
+            if (itemCheck.test(param.item)) {
+                setDrawable(param, param.item);
+                modified = true;
+            }
+        }
+        for (PreviewItemDrawingParams param : mCurrentPageParams) {
+            if (itemCheck.test(param.item)) {
+                setDrawable(param, param.item);
+                modified = true;
+            }
+        }
+        if (modified) {
+            mIcon.invalidate();
+        }
+    }
+
     boolean verifyDrawable(@NonNull Drawable who) {
         for (int i = 0; i < mFirstPageParams.size(); i++) {
             if (mFirstPageParams.get(i).drawable == who) {
@@ -296,46 +329,46 @@ public class PreviewItemManager {
      *  - Moving into a new position
      *  - Moving out of the preview
      *
-     * @param oldParams The list of items in the old preview.
+     * @param oldItems The list of items in the old preview.
-     * @param newParams The list of items in the new preview.
+     * @param newItems The list of items in the new preview.
      * @param dropped The item that was dropped onto the FolderIcon.
      */
-    public void onDrop(List<BubbleTextView> oldParams, List<BubbleTextView> newParams,
+    public void onDrop(List<WorkspaceItemInfo> oldItems, List<WorkspaceItemInfo> newItems,
             WorkspaceItemInfo dropped) {
-        int numItems = newParams.size();
+        int numItems = newItems.size();
         final ArrayList<PreviewItemDrawingParams> params = mFirstPageParams;
         buildParamsForPage(0, params, false);
 
         // New preview items for items that are moving in (except for the dropped item).
-        List<BubbleTextView> moveIn = new ArrayList<>();
+        List<WorkspaceItemInfo> moveIn = new ArrayList<>();
-        for (BubbleTextView btv : newParams) {
+        for (WorkspaceItemInfo newItem : newItems) {
-            if (!oldParams.contains(btv) && !btv.getTag().equals(dropped)) {
+            if (!oldItems.contains(newItem) && !newItem.equals(dropped)) {
-                moveIn.add(btv);
+                moveIn.add(newItem);
             }
         }
         for (int i = 0; i < moveIn.size(); ++i) {
-            int prevIndex = newParams.indexOf(moveIn.get(i));
+            int prevIndex = newItems.indexOf(moveIn.get(i));
             PreviewItemDrawingParams p = params.get(prevIndex);
             computePreviewItemDrawingParams(prevIndex, numItems, p);
-            updateTransitionParam(p, moveIn.get(i), ENTER_INDEX, newParams.indexOf(moveIn.get(i)),
+            updateTransitionParam(p, moveIn.get(i), ENTER_INDEX, newItems.indexOf(moveIn.get(i)),
                     numItems);
         }
 
         // Items that are moving into new positions within the preview.
-        for (int newIndex = 0; newIndex < newParams.size(); ++newIndex) {
+        for (int newIndex = 0; newIndex < newItems.size(); ++newIndex) {
-            int oldIndex = oldParams.indexOf(newParams.get(newIndex));
+            int oldIndex = oldItems.indexOf(newItems.get(newIndex));
             if (oldIndex >= 0 && newIndex != oldIndex) {
                 PreviewItemDrawingParams p = params.get(newIndex);
-                updateTransitionParam(p, newParams.get(newIndex), oldIndex, newIndex, numItems);
+                updateTransitionParam(p, newItems.get(newIndex), oldIndex, newIndex, numItems);
             }
         }
 
         // Old preview items that need to be moved out.
-        List<BubbleTextView> moveOut = new ArrayList<>(oldParams);
+        List<WorkspaceItemInfo> moveOut = new ArrayList<>(oldItems);
-        moveOut.removeAll(newParams);
+        moveOut.removeAll(newItems);
         for (int i = 0; i < moveOut.size(); ++i) {
-            BubbleTextView item = moveOut.get(i);
+            WorkspaceItemInfo item = moveOut.get(i);
-            int oldIndex = oldParams.indexOf(item);
+            int oldIndex = oldItems.indexOf(item);
             PreviewItemDrawingParams p = computePreviewItemDrawingParams(oldIndex, numItems, null);
             updateTransitionParam(p, item, oldIndex, EXIT_INDEX, numItems);
             params.add(0, p); // We want these items first so that they are on drawn last.
@@ -348,14 +381,9 @@ public class PreviewItemManager {
         }
     }
 
-    private void updateTransitionParam(final PreviewItemDrawingParams p, BubbleTextView btv,
+    private void updateTransitionParam(final PreviewItemDrawingParams p, WorkspaceItemInfo item,
             int prevIndex, int newIndex, int numItems) {
-        p.drawable = btv.getCompoundDrawables()[1];
+        setDrawable(p, item);
-        if (!mIcon.mFolder.isOpen()) {
-            // Set the callback to FolderIcon as it is responsible to drawing the icon. The
-            // callback will be released when the folder is opened.
-            p.drawable.setCallback(mIcon);
-        }
 
         FolderPreviewItemAnim anim = new FolderPreviewItemAnim(this, p, prevIndex, numItems,
                 newIndex, numItems, DROP_IN_ANIMATION_DURATION, null);
@@ -364,4 +392,20 @@ public class PreviewItemManager {
         }
         p.anim = anim;
     }
+
+    private void setDrawable(PreviewItemDrawingParams p, WorkspaceItemInfo item) {
+        if (item.hasPromiseIconUi()) {
+            PreloadIconDrawable drawable = mDrawableFactory.newPendingIcon(mContext, item);
+            drawable.setLevel(item.getInstallProgress());
+            p.drawable = drawable;
+        } else {
+            p.drawable = mDrawableFactory.newIcon(mContext, item);
+        }
+        p.drawable.setBounds(0, 0, mIconSize, mIconSize);
+        p.item = item;
+
+        // Set the callback to FolderIcon as it is responsible to drawing the icon. The
+        // callback will be released when the folder is opened.
+        p.drawable.setCallback(mIcon);
+    }
 }