Binding Taskbar directly from Launcher model

This allows taskbar to be loaded even in case of 3P Launchers
and removes dependency on LauncherActivity lifecycle

Bug: 187353581
Bug: 188788621
Test: Manual
Change-Id: I5a0988e0697b41677d4c58f0213aef14ec0c0972
diff --git a/src/com/android/launcher3/CellLayout.java b/src/com/android/launcher3/CellLayout.java
index 00278e4..f4447b1 100644
--- a/src/com/android/launcher3/CellLayout.java
+++ b/src/com/android/launcher3/CellLayout.java
@@ -2147,7 +2147,7 @@
         mShakeAnimators.clear();
     }
 
-    private void commitTempPlacement() {
+    private void commitTempPlacement(View dragView) {
         mTmpOccupied.copyTo(mOccupied);
 
         int screenId = Launcher.cast(mActivity).getWorkspace().getIdForScreen(this);
@@ -2165,7 +2165,7 @@
             ItemInfo info = (ItemInfo) child.getTag();
             // We do a null check here because the item info can be null in the case of the
             // AllApps button in the hotseat.
-            if (info != null) {
+            if (info != null && child != dragView) {
                 final boolean requiresDbUpdate = (info.cellX != lp.tmpCellX
                         || info.cellY != lp.tmpCellY || info.spanX != lp.cellHSpan
                         || info.spanY != lp.cellVSpan);
@@ -2327,7 +2327,7 @@
             animateItemsToSolution(swapSolution, dragView, commit);
 
             if (commit) {
-                commitTempPlacement();
+                commitTempPlacement(null);
                 completeAndClearReorderPreviewAnimations();
                 setItemPlacementDirty(false);
             } else {
@@ -2421,7 +2421,8 @@
 
                 if (!DESTRUCTIVE_REORDER &&
                         (mode == MODE_ON_DROP || mode == MODE_ON_DROP_EXTERNAL)) {
-                    commitTempPlacement();
+                    // Since the temp solution didn't update dragView, don't commit it either
+                    commitTempPlacement(dragView);
                     completeAndClearReorderPreviewAnimations();
                     setItemPlacementDirty(false);
                 } else {
@@ -2877,7 +2878,7 @@
                 directionVector, null, false, configuration).isSolution) {
             if (commitConfig) {
                 copySolutionToTempState(configuration, null);
-                commitTempPlacement();
+                commitTempPlacement(null);
                 // undo marking cells occupied since there is actually nothing being placed yet.
                 mOccupied.markCells(0, mCountY - 1, mCountX, 1, false);
             }
diff --git a/src/com/android/launcher3/Launcher.java b/src/com/android/launcher3/Launcher.java
index 89b44a3..78a8a97 100644
--- a/src/com/android/launcher3/Launcher.java
+++ b/src/com/android/launcher3/Launcher.java
@@ -48,7 +48,6 @@
 import static com.android.launcher3.logging.StatsLogManager.LauncherEvent.LAUNCHER_WIDGET_RECONFIGURED;
 import static com.android.launcher3.model.ItemInstallQueue.FLAG_ACTIVITY_PAUSED;
 import static com.android.launcher3.model.ItemInstallQueue.FLAG_DRAG_AND_DROP;
-import static com.android.launcher3.model.ItemInstallQueue.FLAG_LOADER_RUNNING;
 import static com.android.launcher3.popup.SystemShortcut.APP_INFO;
 import static com.android.launcher3.popup.SystemShortcut.INSTALL;
 import static com.android.launcher3.popup.SystemShortcut.WIDGETS;
@@ -596,7 +595,7 @@
         }
 
         onDeviceProfileInitiated();
-        mModelWriter = mModel.getWriter(getDeviceProfile().isVerticalBarLayout(), true);
+        mModelWriter = mModel.getWriter(getDeviceProfile().isVerticalBarLayout(), true, this);
     }
 
     public RotationHelper getRotationHelper() {
@@ -2598,9 +2597,6 @@
             mPendingActivityResult = null;
         }
 
-        ItemInstallQueue.INSTANCE.get(this)
-                .resumeModelPush(FLAG_LOADER_RUNNING);
-
         int currentPage = pagesBoundFirst != null && !pagesBoundFirst.isEmpty()
                 ? pagesBoundFirst.getArray().get(0) : PagedView.INVALID_PAGE;
         // When undoing the removal of the last item on a page, return to that page.
@@ -2677,7 +2673,7 @@
     @Override
     public void bindWorkspaceItemsChanged(List<WorkspaceItemInfo> updated) {
         if (!updated.isEmpty()) {
-            mWorkspace.updateShortcuts(updated);
+            mWorkspace.updateWorkspaceItems(updated, this);
             PopupContainerWithArrow.dismissInvalidPopup(this);
         }
     }
@@ -2689,7 +2685,7 @@
      */
     @Override
     public void bindRestoreItemsChange(HashSet<ItemInfo> updates) {
-        mWorkspace.updateRestoreItems(updates);
+        mWorkspace.updateRestoreItems(updates, this);
     }
 
     /**
diff --git a/src/com/android/launcher3/LauncherModel.java b/src/com/android/launcher3/LauncherModel.java
index eef3980..6966abf 100644
--- a/src/com/android/launcher3/LauncherModel.java
+++ b/src/com/android/launcher3/LauncherModel.java
@@ -144,9 +144,10 @@
         enqueueModelUpdateTask(new AddWorkspaceItemsTask(itemList));
     }
 
-    public ModelWriter getWriter(boolean hasVerticalHotseat, boolean verifyChanges) {
+    public ModelWriter getWriter(boolean hasVerticalHotseat, boolean verifyChanges,
+            @Nullable Callbacks owner) {
         return new ModelWriter(mApp.getContext(), this, mBgDataModel,
-                hasVerticalHotseat, verifyChanges);
+                hasVerticalHotseat, verifyChanges, owner);
     }
 
     @Override
@@ -329,7 +330,7 @@
     public boolean addCallbacksAndLoad(Callbacks callbacks) {
         synchronized (mLock) {
             addCallbacks(callbacks);
-            return startLoader();
+            return startLoader(new Callbacks[] { callbacks });
 
         }
     }
@@ -349,26 +350,32 @@
      * @return true if the page could be bound synchronously.
      */
     public boolean startLoader() {
+        return startLoader(new Callbacks[0]);
+    }
+
+    private boolean startLoader(Callbacks[] newCallbacks) {
         // Enable queue before starting loader. It will get disabled in Launcher#finishBindingItems
         ItemInstallQueue.INSTANCE.get(mApp.getContext())
                 .pauseModelPush(ItemInstallQueue.FLAG_LOADER_RUNNING);
         synchronized (mLock) {
-            // Don't bother to start the thread if we know it's not going to do anything
-            final Callbacks[] callbacksList = getCallbacks();
+            // If there is already one running, tell it to stop.
+            boolean wasRunning = stopLoader();
+            boolean bindDirectly = mModelLoaded && !mIsLoaderTaskRunning;
+            boolean bindAllCallbacks = wasRunning || !bindDirectly || newCallbacks.length == 0;
+            final Callbacks[] callbacksList = bindAllCallbacks ? getCallbacks() : newCallbacks;
+
             if (callbacksList.length > 0) {
                 // Clear any pending bind-runnables from the synchronized load process.
                 for (Callbacks cb : callbacksList) {
                     MAIN_EXECUTOR.execute(cb::clearPendingBinds);
                 }
 
-                // If there is already one running, tell it to stop.
-                stopLoader();
                 LoaderResults loaderResults = new LoaderResults(
                         mApp, mBgDataModel, mBgAllAppsList, callbacksList);
-                if (mModelLoaded && !mIsLoaderTaskRunning) {
+                if (bindDirectly) {
                     // Divide the set of loaded items into those that we are binding synchronously,
                     // and everything else that is to be bound normally (asynchronously).
-                    loaderResults.bindWorkspace();
+                    loaderResults.bindWorkspace(bindAllCallbacks);
                     // For now, continue posting the binding of AllApps as there are other
                     // issues that arise from that.
                     loaderResults.bindAllApps();
@@ -387,7 +394,7 @@
      * If there is already a loader task running, tell it to stop.
      * @return true if an existing loader was stopped.
      */
-    public boolean stopLoader() {
+    private boolean stopLoader() {
         synchronized (mLock) {
             LoaderTask oldTask = mLoaderTask;
             mLoaderTask = null;
diff --git a/src/com/android/launcher3/Workspace.java b/src/com/android/launcher3/Workspace.java
index 5689394..a585be6 100644
--- a/src/com/android/launcher3/Workspace.java
+++ b/src/com/android/launcher3/Workspace.java
@@ -83,7 +83,6 @@
 import com.android.launcher3.folder.FolderIcon;
 import com.android.launcher3.folder.PreviewBackground;
 import com.android.launcher3.graphics.DragPreviewProvider;
-import com.android.launcher3.graphics.PreloadIconDrawable;
 import com.android.launcher3.icons.BitmapRenderer;
 import com.android.launcher3.icons.FastBitmapDrawable;
 import com.android.launcher3.logger.LauncherAtom;
@@ -105,6 +104,7 @@
 import com.android.launcher3.util.IntArray;
 import com.android.launcher3.util.IntSparseArrayMap;
 import com.android.launcher3.util.ItemInfoMatcher;
+import com.android.launcher3.util.LauncherBindableItemsContainer;
 import com.android.launcher3.util.OverlayEdgeEffect;
 import com.android.launcher3.util.PackageUserKey;
 import com.android.launcher3.util.RunnableList;
@@ -123,7 +123,6 @@
 
 import java.util.ArrayList;
 import java.util.Collections;
-import java.util.HashSet;
 import java.util.List;
 import java.util.function.Predicate;
 import java.util.stream.Collectors;
@@ -136,7 +135,7 @@
 public class Workspace extends PagedView<WorkspacePageIndicator>
         implements DropTarget, DragSource, View.OnTouchListener,
         DragController.DragListener, Insettable, StateHandler<LauncherState>,
-        WorkspaceLayoutManager {
+        WorkspaceLayoutManager, LauncherBindableItemsContainer {
 
     /** The value that {@link #mTransitionProgress} must be greater than for
      * {@link #transitionStateShouldAllowDrop()} to return true. */
@@ -3009,9 +3008,9 @@
      * @param user The user of the app to match.
      */
     public View getFirstMatchForAppClose(int preferredItemId, String packageName, UserHandle user) {
-        final Workspace.ItemOperator preferredItem = (ItemInfo info, View view) ->
+        final ItemOperator preferredItem = (ItemInfo info, View view) ->
                 info != null && info.id == preferredItemId;
-        final Workspace.ItemOperator preferredItemInFolder = (info, view) -> {
+        final ItemOperator preferredItemInFolder = (info, view) -> {
             if (info instanceof FolderInfo) {
                 FolderInfo folderInfo = (FolderInfo) info;
                 for (WorkspaceItemInfo shortcutInfo : folderInfo.contents) {
@@ -3022,14 +3021,14 @@
             }
             return false;
         };
-        final Workspace.ItemOperator packageAndUserAndApp = (ItemInfo info, View view) ->
+        final ItemOperator packageAndUserAndApp = (ItemInfo info, View view) ->
                 info != null
                         && info.itemType == ITEM_TYPE_APPLICATION
                         && info.user.equals(user)
                         && info.getTargetComponent() != null
                         && TextUtils.equals(info.getTargetComponent().getPackageName(),
                                 packageName);
-        final Workspace.ItemOperator packageAndUserAndAppInFolder = (info, view) -> {
+        final ItemOperator packageAndUserAndAppInFolder = (info, view) -> {
             if (info instanceof FolderInfo) {
                 FolderInfo folderInfo = (FolderInfo) info;
                 for (WorkspaceItemInfo shortcutInfo : folderInfo.contents) {
@@ -3148,22 +3147,7 @@
         stripEmptyScreens();
     }
 
-    public interface ItemOperator {
-        /**
-         * Process the next itemInfo, possibly with side-effect on the next item.
-         *
-         * @param info info for the shortcut
-         * @param view view for the shortcut
-         * @return true if done, false to continue the map
-         */
-        boolean evaluate(ItemInfo info, View view);
-    }
-
-    /**
-     * Map the operator over the shortcuts and widgets, return the first-non-null value.
-     *
-     * @param op the operator to map over the shortcuts
-     */
+    @Override
     public void mapOverItems(ItemOperator op) {
         for (CellLayout layout : getWorkspaceAndHotseatCellLayouts()) {
             if (mapOverCellLayout(layout, op) != null) {
@@ -3189,31 +3173,6 @@
         return null;
     }
 
-    void updateShortcuts(List<WorkspaceItemInfo> shortcuts) {
-        final HashSet<WorkspaceItemInfo> updates = new HashSet<>(shortcuts);
-        ItemOperator op = (info, v) -> {
-            if (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);
-            }
-
-            // Iterate all items
-            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);
         Predicate<ItemInfo> matcher = info -> !packageUserKey.updateFromItemInfo(info)
@@ -3253,28 +3212,6 @@
         removeItemsByMatcher(matcher);
     }
 
-    public void updateRestoreItems(final HashSet<ItemInfo> updates) {
-        ItemOperator op = (info, v) -> {
-            if (info instanceof WorkspaceItemInfo && v instanceof BubbleTextView
-                    && updates.contains(info)) {
-                ((BubbleTextView) v).applyLoadingState(false /* promiseStateChanged */);
-            } else if (v instanceof PendingAppWidgetHostView
-                    && 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) {
         if (!changedInfo.isEmpty()) {
             DeferredWidgetRefresh widgetRefresh = new DeferredWidgetRefresh(changedInfo,
diff --git a/src/com/android/launcher3/folder/Folder.java b/src/com/android/launcher3/folder/Folder.java
index 22bb56c..7187188 100644
--- a/src/com/android/launcher3/folder/Folder.java
+++ b/src/com/android/launcher3/folder/Folder.java
@@ -75,7 +75,6 @@
 import com.android.launcher3.R;
 import com.android.launcher3.ShortcutAndWidgetContainer;
 import com.android.launcher3.Utilities;
-import com.android.launcher3.Workspace.ItemOperator;
 import com.android.launcher3.accessibility.AccessibleDragListenerAdapter;
 import com.android.launcher3.accessibility.FolderAccessibilityHelper;
 import com.android.launcher3.anim.KeyboardInsetAnimationCallback;
@@ -94,6 +93,7 @@
 import com.android.launcher3.model.data.WorkspaceItemInfo;
 import com.android.launcher3.pageindicators.PageIndicatorDots;
 import com.android.launcher3.util.Executors;
+import com.android.launcher3.util.LauncherBindableItemsContainer.ItemOperator;
 import com.android.launcher3.util.Thunk;
 import com.android.launcher3.views.ActivityContext;
 import com.android.launcher3.views.BaseDragLayer;
@@ -1196,8 +1196,7 @@
     }
 
     void replaceFolderWithFinalItem() {
-        mLauncherDelegate.replaceFolderWithFinalItem(this);
-        mDestroyed = true;
+        mDestroyed = mLauncherDelegate.replaceFolderWithFinalItem(this);
     }
 
     public boolean isDestroyed() {
diff --git a/src/com/android/launcher3/folder/FolderIcon.java b/src/com/android/launcher3/folder/FolderIcon.java
index d076be6..f005b61 100644
--- a/src/com/android/launcher3/folder/FolderIcon.java
+++ b/src/com/android/launcher3/folder/FolderIcon.java
@@ -679,6 +679,7 @@
 
     @Override
     public void onAdd(WorkspaceItemInfo item, int rank) {
+        updatePreviewItems(false);
         boolean wasDotted = mDotInfo.hasDot();
         mDotInfo.addDotInfo(mActivity.getDotInfoForItem(item));
         boolean isDotted = mDotInfo.hasDot();
@@ -690,6 +691,7 @@
 
     @Override
     public void onRemove(List<WorkspaceItemInfo> items) {
+        updatePreviewItems(false);
         boolean wasDotted = mDotInfo.hasDot();
         items.stream().map(mActivity::getDotInfoForItem).forEach(mDotInfo::subtractDotInfo);
         boolean isDotted = mDotInfo.hasDot();
diff --git a/src/com/android/launcher3/folder/FolderPagedView.java b/src/com/android/launcher3/folder/FolderPagedView.java
index 3d2884a..65991e4 100644
--- a/src/com/android/launcher3/folder/FolderPagedView.java
+++ b/src/com/android/launcher3/folder/FolderPagedView.java
@@ -41,12 +41,12 @@
 import com.android.launcher3.R;
 import com.android.launcher3.ShortcutAndWidgetContainer;
 import com.android.launcher3.Utilities;
-import com.android.launcher3.Workspace.ItemOperator;
 import com.android.launcher3.keyboard.ViewGroupFocusHelper;
 import com.android.launcher3.model.data.ItemInfo;
 import com.android.launcher3.model.data.WorkspaceItemInfo;
 import com.android.launcher3.pageindicators.PageIndicatorDots;
 import com.android.launcher3.touch.ItemClickHandler;
+import com.android.launcher3.util.LauncherBindableItemsContainer.ItemOperator;
 import com.android.launcher3.util.Thunk;
 import com.android.launcher3.util.ViewCache;
 import com.android.launcher3.views.ActivityContext;
diff --git a/src/com/android/launcher3/folder/LauncherDelegate.java b/src/com/android/launcher3/folder/LauncherDelegate.java
index f7d8e8c..e599e8c 100644
--- a/src/com/android/launcher3/folder/LauncherDelegate.java
+++ b/src/com/android/launcher3/folder/LauncherDelegate.java
@@ -93,7 +93,7 @@
         }
     }
 
-    void replaceFolderWithFinalItem(Folder folder) {
+    boolean replaceFolderWithFinalItem(Folder folder) {
         // Add the last remaining child to the workspace in place of the folder
         Runnable onCompleteRunnable = new Runnable() {
             @Override
@@ -147,6 +147,7 @@
         } else {
             onCompleteRunnable.run();
         }
+        return true;
     }
 
 
@@ -191,7 +192,7 @@
         ModelWriter getModelWriter() {
             if (mWriter == null) {
                 mWriter = LauncherAppState.getInstance((Context) mContext).getModel()
-                        .getWriter(false, false);
+                        .getWriter(false, false, null);
             }
             return mWriter;
         }
@@ -205,7 +206,9 @@
         }
 
         @Override
-        void replaceFolderWithFinalItem(Folder folder) { }
+        boolean replaceFolderWithFinalItem(Folder folder) {
+            return false;
+        }
 
         @Override
         boolean interceptOutsideTouch(MotionEvent ev, BaseDragLayer dl, Folder folder) {
diff --git a/src/com/android/launcher3/model/BaseLoaderResults.java b/src/com/android/launcher3/model/BaseLoaderResults.java
index 30755e3..c202d8d 100644
--- a/src/com/android/launcher3/model/BaseLoaderResults.java
+++ b/src/com/android/launcher3/model/BaseLoaderResults.java
@@ -16,6 +16,7 @@
 
 package com.android.launcher3.model;
 
+import static com.android.launcher3.model.ItemInstallQueue.FLAG_LOADER_RUNNING;
 import static com.android.launcher3.model.ModelUtils.filterCurrentWorkspaceItems;
 import static com.android.launcher3.model.ModelUtils.sortWorkspaceItemsSpatially;
 import static com.android.launcher3.util.Executors.MODEL_EXECUTOR;
@@ -73,7 +74,7 @@
     /**
      * Binds all loaded data to actual views on the main thread.
      */
-    public void bindWorkspace() {
+    public void bindWorkspace(boolean incrementBindId) {
         // Save a copy of all the bg-thread collections
         ArrayList<ItemInfo> workspaceItems = new ArrayList<>();
         ArrayList<LauncherAppWidgetInfo> appWidgets = new ArrayList<>();
@@ -85,7 +86,9 @@
             appWidgets.addAll(mBgDataModel.appWidgets);
             orderedScreenIds.addAll(mBgDataModel.collectWorkspaceScreens());
             mBgDataModel.extraItems.forEach(extraItems::add);
-            mBgDataModel.lastBindId++;
+            if (incrementBindId) {
+                mBgDataModel.lastBindId++;
+            }
             mMyBindingId = mBgDataModel.lastBindId;
         }
 
@@ -217,7 +220,11 @@
             bindAppWidgets(otherAppWidgets, pendingExecutor);
             executeCallbacksTask(c -> c.finishBindingItems(currentScreenIndices), pendingExecutor);
             pendingExecutor.execute(
-                    () -> MODEL_EXECUTOR.setThreadPriority(Process.THREAD_PRIORITY_DEFAULT));
+                    () -> {
+                        MODEL_EXECUTOR.setThreadPriority(Process.THREAD_PRIORITY_DEFAULT);
+                        ItemInstallQueue.INSTANCE.get(mApp.getContext())
+                                .resumeModelPush(FLAG_LOADER_RUNNING);
+                    });
 
             executeCallbacksTask(
                     c -> {
diff --git a/src/com/android/launcher3/model/BaseModelUpdateTask.java b/src/com/android/launcher3/model/BaseModelUpdateTask.java
index ad553d5..a3a4717 100644
--- a/src/com/android/launcher3/model/BaseModelUpdateTask.java
+++ b/src/com/android/launcher3/model/BaseModelUpdateTask.java
@@ -90,7 +90,7 @@
     public ModelWriter getModelWriter() {
         // Updates from model task, do not deal with icon position in hotseat. Also no need to
         // verify changes as the ModelTasks always push the changes to callbacks
-        return mModel.getWriter(false /* hasVerticalHotseat */, false /* verifyChanges */);
+        return mModel.getWriter(false /* hasVerticalHotseat */, false /* verifyChanges */, null);
     }
 
     public void bindUpdatedWorkspaceItems(List<WorkspaceItemInfo> allUpdates) {
diff --git a/src/com/android/launcher3/model/BgDataModel.java b/src/com/android/launcher3/model/BgDataModel.java
index ba825ca..dd4c3c3 100644
--- a/src/com/android/launcher3/model/BgDataModel.java
+++ b/src/com/android/launcher3/model/BgDataModel.java
@@ -477,6 +477,11 @@
                 ArrayList<ItemInfo> addNotAnimated, ArrayList<ItemInfo> addAnimated) { }
 
         /**
+         * Called when some persistent property of an item is modified
+         */
+        default void bindItemsModified(List<ItemInfo> items) { }
+
+        /**
          * Binds updated incremental download progress
          */
         default void bindIncrementalDownloadProgressUpdated(AppInfo app) { }
diff --git a/src/com/android/launcher3/model/LoaderTask.java b/src/com/android/launcher3/model/LoaderTask.java
index d5b5452..31ca6e7 100644
--- a/src/com/android/launcher3/model/LoaderTask.java
+++ b/src/com/android/launcher3/model/LoaderTask.java
@@ -210,7 +210,7 @@
             }
 
             verifyNotStopped();
-            mResults.bindWorkspace();
+            mResults.bindWorkspace(true /* incrementBindId */);
             logASplit(logger, "bindWorkspace");
 
             mModelDelegate.workspaceLoadComplete();
diff --git a/src/com/android/launcher3/model/ModelWriter.java b/src/com/android/launcher3/model/ModelWriter.java
index 2b93118..55edfd4 100644
--- a/src/com/android/launcher3/model/ModelWriter.java
+++ b/src/com/android/launcher3/model/ModelWriter.java
@@ -23,12 +23,13 @@
 import android.content.ContentValues;
 import android.content.Context;
 import android.net.Uri;
-import android.os.Handler;
-import android.os.Looper;
 import android.util.Log;
 
+import androidx.annotation.Nullable;
+
 import com.android.launcher3.LauncherAppState;
 import com.android.launcher3.LauncherModel;
+import com.android.launcher3.LauncherModel.CallbackTask;
 import com.android.launcher3.LauncherProvider;
 import com.android.launcher3.LauncherSettings;
 import com.android.launcher3.LauncherSettings.Favorites;
@@ -36,19 +37,22 @@
 import com.android.launcher3.Utilities;
 import com.android.launcher3.config.FeatureFlags;
 import com.android.launcher3.logging.FileLog;
+import com.android.launcher3.model.BgDataModel.Callbacks;
 import com.android.launcher3.model.data.FolderInfo;
 import com.android.launcher3.model.data.ItemInfo;
 import com.android.launcher3.model.data.LauncherAppWidgetInfo;
 import com.android.launcher3.model.data.WorkspaceItemInfo;
 import com.android.launcher3.util.ContentWriter;
+import com.android.launcher3.util.Executors;
 import com.android.launcher3.util.ItemInfoMatcher;
+import com.android.launcher3.util.LooperExecutor;
 import com.android.launcher3.widget.LauncherAppWidgetHost;
 
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
+import java.util.Collections;
 import java.util.List;
-import java.util.concurrent.Executor;
 import java.util.function.Supplier;
 import java.util.stream.Collectors;
 import java.util.stream.StreamSupport;
@@ -63,7 +67,10 @@
     private final Context mContext;
     private final LauncherModel mModel;
     private final BgDataModel mBgDataModel;
-    private final Handler mUiHandler;
+    private final LooperExecutor mUiExecutor;
+
+    @Nullable
+    private final Callbacks mOwner;
 
     private final boolean mHasVerticalHotseat;
     private final boolean mVerifyChanges;
@@ -73,13 +80,15 @@
     private boolean mPreparingToUndo;
 
     public ModelWriter(Context context, LauncherModel model, BgDataModel dataModel,
-            boolean hasVerticalHotseat, boolean verifyChanges) {
+            boolean hasVerticalHotseat, boolean verifyChanges,
+            @Nullable Callbacks owner) {
         mContext = context;
         mModel = model;
         mBgDataModel = dataModel;
         mHasVerticalHotseat = hasVerticalHotseat;
         mVerifyChanges = verifyChanges;
-        mUiHandler = new Handler(Looper.getMainLooper());
+        mOwner = owner;
+        mUiExecutor = Executors.MAIN_EXECUTOR;
     }
 
     private void updateItemInfoProps(
@@ -162,6 +171,8 @@
     public void moveItemInDatabase(final ItemInfo item,
             int container, int screenId, int cellX, int cellY) {
         updateItemInfoProps(item, container, screenId, cellX, cellY);
+        notifyItemModified(item);
+
         enqueueDeleteRunnable(new UpdateItemRunnable(item, () ->
                 new ContentWriter(mContext)
                         .put(Favorites.CONTAINER, item.container)
@@ -178,6 +189,7 @@
     public void moveItemsInDatabase(final ArrayList<ItemInfo> items, int container, int screen) {
         ArrayList<ContentValues> contentValues = new ArrayList<>();
         int count = items.size();
+        notifyOtherCallbacks(c -> c.bindItemsModified(items));
 
         for (int i = 0; i < count; i++) {
             ItemInfo item = items.get(i);
@@ -203,8 +215,9 @@
         updateItemInfoProps(item, container, screenId, cellX, cellY);
         item.spanX = spanX;
         item.spanY = spanY;
+        notifyItemModified(item);
 
-        ((Executor) MODEL_EXECUTOR).execute(new UpdateItemRunnable(item, () ->
+        MODEL_EXECUTOR.execute(new UpdateItemRunnable(item, () ->
                 new ContentWriter(mContext)
                         .put(Favorites.CONTAINER, item.container)
                         .put(Favorites.CELLX, item.cellX)
@@ -219,13 +232,18 @@
      * Update an item to the database in a specified container.
      */
     public void updateItemInDatabase(ItemInfo item) {
-        ((Executor) MODEL_EXECUTOR).execute(new UpdateItemRunnable(item, () -> {
+        notifyItemModified(item);
+        MODEL_EXECUTOR.execute(new UpdateItemRunnable(item, () -> {
             ContentWriter writer = new ContentWriter(mContext);
             item.onAddToDatabase(writer);
             return writer;
         }));
     }
 
+    private void notifyItemModified(ItemInfo item) {
+        notifyOtherCallbacks(c -> c.bindItemsModified(Collections.singletonList(item)));
+    }
+
     /**
      * Add an item to the database in a specified container. Sets the container, screen, cellX and
      * cellY fields of the item. Also assigns an ID to the item.
@@ -236,10 +254,11 @@
 
         final ContentResolver cr = mContext.getContentResolver();
         item.id = Settings.call(cr, Settings.METHOD_NEW_ITEM_ID).getInt(Settings.EXTRA_VALUE);
+        notifyOtherCallbacks(c -> c.bindItems(Collections.singletonList(item), false));
 
         ModelVerifier verifier = new ModelVerifier();
         final StackTraceElement[] stackTrace = new Throwable().getStackTrace();
-        ((Executor) MODEL_EXECUTOR).execute(() -> {
+        MODEL_EXECUTOR.execute(() -> {
             // Write the item on background thread, as some properties might have been updated in
             // the background.
             final ContentWriter writer = new ContentWriter(mContext);
@@ -281,6 +300,7 @@
                 (item) -> item.getTargetComponent() == null ? ""
                         : item.getTargetComponent().getPackageName()).collect(
                 Collectors.joining(",")), new Exception());
+        notifyDelete(items);
         enqueueDeleteRunnable(() -> {
             for (ItemInfo item : items) {
                 final Uri uri = Favorites.getContentUri(item.id);
@@ -297,6 +317,7 @@
      */
     public void deleteFolderAndContentsFromDatabase(final FolderInfo info) {
         ModelVerifier verifier = new ModelVerifier();
+        notifyDelete(Collections.singleton(info));
 
         enqueueDeleteRunnable(() -> {
             ContentResolver cr = mContext.getContentResolver();
@@ -315,6 +336,7 @@
      * Deletes the widget info and the widget id.
      */
     public void deleteWidgetInfo(final LauncherAppWidgetInfo info, LauncherAppWidgetHost host) {
+        notifyDelete(Collections.singleton(info));
         if (host != null && !info.isCustomWidget() && info.isWidgetIdAllocated()) {
             // Deleting an app widget ID is a void call but writes to disk before returning
             // to the caller...
@@ -323,6 +345,10 @@
         deleteItemFromDatabase(info);
     }
 
+    private void notifyDelete(Collection<? extends ItemInfo> items) {
+        notifyOtherCallbacks(c -> c.bindWorkspaceComponentsRemoved(ItemInfoMatcher.ofItems(items)));
+    }
+
     /**
      * Delete operations tracked using {@link #enqueueDeleteRunnable} will only be called
      * if {@link #commitDelete} is called. Note that one of {@link #commitDelete()} or
@@ -348,14 +374,14 @@
         if (mPreparingToUndo) {
             mDeleteRunnables.add(r);
         } else {
-            ((Executor) MODEL_EXECUTOR).execute(r);
+            MODEL_EXECUTOR.execute(r);
         }
     }
 
     public void commitDelete() {
         mPreparingToUndo = false;
         for (Runnable runnable : mDeleteRunnables) {
-            ((Executor) MODEL_EXECUTOR).execute(runnable);
+            MODEL_EXECUTOR.execute(runnable);
         }
         mDeleteRunnables.clear();
     }
@@ -371,6 +397,20 @@
         mModel.forceReload();
     }
 
+    private void notifyOtherCallbacks(CallbackTask task) {
+        if (mOwner == null) {
+            // If the call is happening from a model, it will take care of updating the callbacks
+            return;
+        }
+        mUiExecutor.execute(() -> {
+            for (Callbacks c : mModel.getCallbacks()) {
+                if (c != mOwner) {
+                    task.execute(c);
+                }
+            }
+        });
+    }
+
     private class UpdateItemRunnable extends UpdateItemBaseRunnable {
         private final ItemInfo mItem;
         private final Supplier<ContentWriter> mWriter;
@@ -491,7 +531,7 @@
 
             int executeId = mBgDataModel.lastBindId;
 
-            mUiHandler.post(() -> {
+            mUiExecutor.post(() -> {
                 int currentId = mBgDataModel.lastBindId;
                 if (currentId > executeId) {
                     // Model was already bound after job was executed.
diff --git a/src/com/android/launcher3/util/ItemInfoMatcher.java b/src/com/android/launcher3/util/ItemInfoMatcher.java
index 354609d..e8ba28f 100644
--- a/src/com/android/launcher3/util/ItemInfoMatcher.java
+++ b/src/com/android/launcher3/util/ItemInfoMatcher.java
@@ -23,6 +23,7 @@
 import com.android.launcher3.model.data.ItemInfo;
 import com.android.launcher3.shortcuts.ShortcutKey;
 
+import java.util.Collection;
 import java.util.HashSet;
 import java.util.Set;
 
@@ -89,4 +90,13 @@
     static ItemInfoMatcher ofItemIds(IntSet ids) {
         return (info, cn) -> ids.contains(info.id);
     }
+
+    /**
+     * Returns a matcher for items with provided items
+     */
+    static ItemInfoMatcher ofItems(Collection<? extends ItemInfo> items) {
+        IntSet ids = new IntSet();
+        items.forEach(item -> ids.add(item.id));
+        return ofItemIds(ids);
+    }
 }
diff --git a/src/com/android/launcher3/util/LauncherBindableItemsContainer.java b/src/com/android/launcher3/util/LauncherBindableItemsContainer.java
new file mode 100644
index 0000000..a4cb30a
--- /dev/null
+++ b/src/com/android/launcher3/util/LauncherBindableItemsContainer.java
@@ -0,0 +1,113 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.android.launcher3.util;
+
+import android.graphics.drawable.Drawable;
+import android.view.View;
+
+import com.android.launcher3.BubbleTextView;
+import com.android.launcher3.folder.Folder;
+import com.android.launcher3.folder.FolderIcon;
+import com.android.launcher3.graphics.PreloadIconDrawable;
+import com.android.launcher3.model.data.FolderInfo;
+import com.android.launcher3.model.data.ItemInfo;
+import com.android.launcher3.model.data.LauncherAppWidgetInfo;
+import com.android.launcher3.model.data.WorkspaceItemInfo;
+import com.android.launcher3.views.ActivityContext;
+import com.android.launcher3.widget.PendingAppWidgetHostView;
+
+import java.util.HashSet;
+import java.util.List;
+
+/**
+ * Interface representing a container which can bind Launcher items with some utility methods
+ */
+public interface LauncherBindableItemsContainer {
+
+    /**
+     * Called to update workspace items as a result of
+     * {@link com.android.launcher3.model.BgDataModel.Callbacks#bindWorkspaceItemsChanged(List)}
+     */
+    default void updateWorkspaceItems(List<WorkspaceItemInfo> shortcuts, ActivityContext context) {
+        final HashSet<WorkspaceItemInfo> updates = new HashSet<>(shortcuts);
+        ItemOperator op = (info, v) -> {
+            if (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);
+            }
+
+            // Iterate all items
+            return false;
+        };
+
+        mapOverItems(op);
+        Folder openFolder = Folder.getOpen(context);
+        if (openFolder != null) {
+            openFolder.iterateOverItems(op);
+        }
+    }
+
+    /**
+     * Called to update restored items as a result of
+     * {@link com.android.launcher3.model.BgDataModel.Callbacks#bindRestoreItemsChange(HashSet)}}
+     */
+    default void updateRestoreItems(final HashSet<ItemInfo> updates, ActivityContext context) {
+        ItemOperator op = (info, v) -> {
+            if (info instanceof WorkspaceItemInfo && v instanceof BubbleTextView
+                    && updates.contains(info)) {
+                ((BubbleTextView) v).applyLoadingState(false /* promiseStateChanged */);
+            } else if (v instanceof PendingAppWidgetHostView
+                    && 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(context);
+        if (folder != null) {
+            folder.iterateOverItems(op);
+        }
+    }
+
+    /**
+     * Map the operator over the shortcuts and widgets.
+     *
+     * @param op the operator to map over the shortcuts
+     */
+    void mapOverItems(ItemOperator op);
+
+    interface ItemOperator {
+        /**
+         * Process the next itemInfo, possibly with side-effect on the next item.
+         *
+         * @param info info for the shortcut
+         * @param view view for the shortcut
+         * @return true if done, false to continue the map
+         */
+        boolean evaluate(ItemInfo info, View view);
+    }
+}