diff --git a/go/src/com/android/launcher3/model/LoaderResults.java b/go/src/com/android/launcher3/model/LoaderResults.java
index 26c3313..7130531 100644
--- a/go/src/com/android/launcher3/model/LoaderResults.java
+++ b/go/src/com/android/launcher3/model/LoaderResults.java
@@ -16,10 +16,11 @@
 
 package com.android.launcher3.model;
 
+import static com.android.launcher3.util.Executors.MAIN_EXECUTOR;
+
 import com.android.launcher3.LauncherAppState;
 import com.android.launcher3.model.BgDataModel.Callbacks;
-
-import java.lang.ref.WeakReference;
+import com.android.launcher3.util.LooperExecutor;
 
 /**
  * Helper class to handle results of {@link com.android.launcher3.model.LoaderTask}.
@@ -27,8 +28,13 @@
 public class LoaderResults extends BaseLoaderResults {
 
     public LoaderResults(LauncherAppState app, BgDataModel dataModel,
-            AllAppsList allAppsList, int pageToBindFirst, WeakReference<Callbacks> callbacks) {
-        super(app, dataModel, allAppsList, pageToBindFirst, callbacks);
+            AllAppsList allAppsList, Callbacks[] callbacks) {
+        this(app, dataModel, allAppsList, callbacks, MAIN_EXECUTOR);
+    }
+
+    public LoaderResults(LauncherAppState app, BgDataModel dataModel,
+            AllAppsList allAppsList, Callbacks[] callbacks, LooperExecutor executor) {
+        super(app, dataModel, allAppsList, callbacks, executor);
     }
 
     @Override
diff --git a/quickstep/recents_ui_overrides/src/com/android/launcher3/hybridhotseat/HotseatEduController.java b/quickstep/recents_ui_overrides/src/com/android/launcher3/hybridhotseat/HotseatEduController.java
index 0fd4aac..923e050 100644
--- a/quickstep/recents_ui_overrides/src/com/android/launcher3/hybridhotseat/HotseatEduController.java
+++ b/quickstep/recents_ui_overrides/src/com/android/launcher3/hybridhotseat/HotseatEduController.java
@@ -77,7 +77,7 @@
     }
 
     void finishOnboarding() {
-        mLauncher.rebindModel();
+        mLauncher.getModel().rebindCallbacks();
         mLauncher.getSharedPrefs().edit().putBoolean(KEY_HOTSEAT_EDU_SEEN, true).apply();
         removeNotification();
     }
diff --git a/robolectric_tests/src/com/android/launcher3/model/AddWorkspaceItemsTaskTest.java b/robolectric_tests/src/com/android/launcher3/model/AddWorkspaceItemsTaskTest.java
index ea7c137..b7f2243 100644
--- a/robolectric_tests/src/com/android/launcher3/model/AddWorkspaceItemsTaskTest.java
+++ b/robolectric_tests/src/com/android/launcher3/model/AddWorkspaceItemsTaskTest.java
@@ -127,7 +127,7 @@
     @Test
     public void testAddItem_some_items_added() throws Exception {
         Callbacks callbacks = mock(Callbacks.class);
-        mModelHelper.getModel().initialize(callbacks);
+        mModelHelper.getModel().addCallbacks(callbacks);
 
         WorkspaceItemInfo info = new WorkspaceItemInfo();
         info.intent = new Intent().setComponent(mComponent1);
diff --git a/robolectric_tests/src/com/android/launcher3/model/DefaultLayoutProviderTest.java b/robolectric_tests/src/com/android/launcher3/model/DefaultLayoutProviderTest.java
index e0ddcb1..f8ac010 100644
--- a/robolectric_tests/src/com/android/launcher3/model/DefaultLayoutProviderTest.java
+++ b/robolectric_tests/src/com/android/launcher3/model/DefaultLayoutProviderTest.java
@@ -16,8 +16,9 @@
 
 package com.android.launcher3.model;
 
+import static com.android.launcher3.util.LauncherModelHelper.TEST_PACKAGE;
+
 import static org.junit.Assert.assertEquals;
-import static org.mockito.Mockito.mock;
 import static org.robolectric.Shadows.shadowOf;
 import static org.robolectric.util.ReflectionHelpers.setField;
 
@@ -26,14 +27,10 @@
 import android.content.pm.PackageInstaller;
 import android.content.pm.PackageInstaller.SessionInfo;
 import android.content.pm.PackageInstaller.SessionParams;
-import android.net.Uri;
-import android.provider.Settings;
 
 import com.android.launcher3.FolderInfo;
-import com.android.launcher3.InvariantDeviceProfile;
 import com.android.launcher3.ItemInfo;
 import com.android.launcher3.LauncherAppState;
-import com.android.launcher3.LauncherProvider;
 import com.android.launcher3.LauncherSettings;
 import com.android.launcher3.icons.BitmapInfo;
 import com.android.launcher3.model.BgDataModel.Callbacks;
@@ -48,12 +45,7 @@
 import org.robolectric.RuntimeEnvironment;
 import org.robolectric.annotation.LooperMode;
 import org.robolectric.annotation.LooperMode.Mode;
-import org.robolectric.shadows.ShadowPackageManager;
 
-import java.io.ByteArrayInputStream;
-import java.io.ByteArrayOutputStream;
-import java.io.OutputStreamWriter;
-import java.lang.ref.WeakReference;
 import java.util.ArrayList;
 
 /**
@@ -63,40 +55,22 @@
 @LooperMode(Mode.PAUSED)
 public class DefaultLayoutProviderTest {
 
-    private static final String SETTINGS_APP = "com.android.settings";
-    private static final String TEST_PROVIDER_AUTHORITY =
-            DefaultLayoutProviderTest.class.getName().toLowerCase();
-
-    private static final int BITMAP_SIZE = 10;
-    private static final int GRID_SIZE = 4;
-
     private LauncherModelHelper mModelHelper;
     private Context mTargetContext;
-    private InvariantDeviceProfile mIdp;
 
     @Before
     public void setUp() {
         mModelHelper = new LauncherModelHelper();
         mTargetContext = RuntimeEnvironment.application;
 
-        mIdp = InvariantDeviceProfile.INSTANCE.get(mTargetContext);
-        mIdp.numRows = mIdp.numColumns = mIdp.numHotseatIcons = GRID_SIZE;
-        mIdp.iconBitmapSize = BITMAP_SIZE;
-
-        mModelHelper.provider.setAllowLoadDefaultFavorites(true);
-        Settings.Secure.putString(mTargetContext.getContentResolver(),
-                "launcher3.layout.provider", TEST_PROVIDER_AUTHORITY);
-
-        ShadowPackageManager spm = shadowOf(mTargetContext.getPackageManager());
-        spm.addProviderIfNotPresent(new ComponentName("com.test", "Dummy")).authority =
-                TEST_PROVIDER_AUTHORITY;
-        spm.addActivityIfNotPresent(new ComponentName(SETTINGS_APP, SETTINGS_APP));
+        shadowOf(mTargetContext.getPackageManager())
+                .addActivityIfNotPresent(new ComponentName(TEST_PACKAGE, TEST_PACKAGE));
     }
 
     @Test
     public void testCustomProfileLoaded_with_icon_on_hotseat() throws Exception {
         writeLayoutAndLoad(new LauncherLayoutBuilder().atHotseat(0)
-                .putApp(SETTINGS_APP, SETTINGS_APP));
+                .putApp(TEST_PACKAGE, TEST_PACKAGE));
 
         // Verify one item in hotseat
         assertEquals(1, mModelHelper.getBgDataModel().workspaceItems.size());
@@ -108,9 +82,9 @@
     @Test
     public void testCustomProfileLoaded_with_folder() throws Exception {
         writeLayoutAndLoad(new LauncherLayoutBuilder().atHotseat(0).putFolder(android.R.string.copy)
-                .addApp(SETTINGS_APP, SETTINGS_APP)
-                .addApp(SETTINGS_APP, SETTINGS_APP)
-                .addApp(SETTINGS_APP, SETTINGS_APP)
+                .addApp(TEST_PACKAGE, TEST_PACKAGE)
+                .addApp(TEST_PACKAGE, TEST_PACKAGE)
+                .addApp(TEST_PACKAGE, TEST_PACKAGE)
                 .build());
 
         // Verify folder
@@ -146,19 +120,13 @@
     }
 
     private void writeLayoutAndLoad(LauncherLayoutBuilder builder) throws Exception {
-        ByteArrayOutputStream bos = new ByteArrayOutputStream();
-        builder.build(new OutputStreamWriter(bos));
-
-        Uri layoutUri = LauncherProvider.getLayoutUri(TEST_PROVIDER_AUTHORITY, mTargetContext);
-        shadowOf(mTargetContext.getContentResolver()).registerInputStream(layoutUri,
-                new ByteArrayInputStream(bos.toByteArray()));
+        mModelHelper.setupDefaultLayoutProvider(builder);
 
         LoaderResults results = new LoaderResults(
                 LauncherAppState.getInstance(mTargetContext),
                 mModelHelper.getBgDataModel(),
                 mModelHelper.getAllAppsList(),
-                0,
-                new WeakReference<>(mock(Callbacks.class)));
+                new Callbacks[0]);
         LoaderTask task = new LoaderTask(
                 LauncherAppState.getInstance(mTargetContext),
                 mModelHelper.getAllAppsList(),
diff --git a/robolectric_tests/src/com/android/launcher3/model/GridSizeMigrationTaskTest.java b/robolectric_tests/src/com/android/launcher3/model/GridSizeMigrationTaskTest.java
index 8dd7588..1ed4bca 100644
--- a/robolectric_tests/src/com/android/launcher3/model/GridSizeMigrationTaskTest.java
+++ b/robolectric_tests/src/com/android/launcher3/model/GridSizeMigrationTaskTest.java
@@ -190,7 +190,7 @@
 
     @Test
     public void testWorkspace_items_not_merged_in_next_screen() throws Exception {
-        // First screen has 2 items that need to be moved, but second screen has only one
+        // First screen has 2 mItems that need to be moved, but second screen has only one
         // empty space after migration (top-left corner)
         int[][][] ids = mModelHelper.createGrid(new int[][][]{{
                 {  0,  0,  0,  1},
@@ -277,7 +277,7 @@
     }
 
     /**
-     * Verifies that the workspace items are arranged in the provided order.
+     * Verifies that the workspace mItems are arranged in the provided order.
      * @param ids A 3d array where the first dimension represents the screen, and the rest two
      *            represent the workspace grid.
      */
diff --git a/robolectric_tests/src/com/android/launcher3/model/LoaderCursorTest.java b/robolectric_tests/src/com/android/launcher3/model/LoaderCursorTest.java
index 4854314..7fa3ee9 100644
--- a/robolectric_tests/src/com/android/launcher3/model/LoaderCursorTest.java
+++ b/robolectric_tests/src/com/android/launcher3/model/LoaderCursorTest.java
@@ -46,7 +46,6 @@
 import android.content.ComponentName;
 import android.content.Context;
 import android.content.Intent;
-import android.content.pm.LauncherApps;
 import android.database.MatrixCursor;
 import android.os.Process;
 
@@ -77,7 +76,6 @@
     private MatrixCursor mCursor;
     private InvariantDeviceProfile mIDP;
     private Context mContext;
-    private LauncherApps mLauncherApps;
 
     private LoaderCursor mLoaderCursor;
 
@@ -86,7 +84,6 @@
         mContext = RuntimeEnvironment.application;
         mIDP = InvariantDeviceProfile.INSTANCE.get(mContext);
         mApp = LauncherAppState.getInstance(mContext);
-        mLauncherApps = mContext.getSystemService(LauncherApps.class);
 
         mCursor = new MatrixCursor(new String[] {
                 ICON, ICON_PACKAGE, ICON_RESOURCE, TITLE,
@@ -174,7 +171,7 @@
         mIDP.numColumns = 4;
         mIDP.numHotseatIcons = 3;
 
-        // Overlapping items are not placed
+        // Overlapping mItems are not placed
         assertTrue(mLoaderCursor.checkItemPlacement(
                 newItemInfo(0, 0, 1, 1, CONTAINER_DESKTOP, 1)));
         assertFalse(mLoaderCursor.checkItemPlacement(
@@ -200,7 +197,7 @@
         mIDP.numColumns = 4;
         mIDP.numHotseatIcons = 3;
 
-        // Hotseat items are only placed based on screenId
+        // Hotseat mItems are only placed based on screenId
         assertTrue(mLoaderCursor.checkItemPlacement(
                 newItemInfo(3, 3, 1, 1, CONTAINER_HOTSEAT, 1)));
         assertTrue(mLoaderCursor.checkItemPlacement(
diff --git a/robolectric_tests/src/com/android/launcher3/model/ModelMultiCallbacksTest.java b/robolectric_tests/src/com/android/launcher3/model/ModelMultiCallbacksTest.java
new file mode 100644
index 0000000..c7979b2
--- /dev/null
+++ b/robolectric_tests/src/com/android/launcher3/model/ModelMultiCallbacksTest.java
@@ -0,0 +1,238 @@
+/*
+ * Copyright (C) 2020 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.model;
+
+import static com.android.launcher3.util.Executors.createAndStartNewForegroundLooper;
+import static com.android.launcher3.util.LauncherModelHelper.TEST_PACKAGE;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertNull;
+import static org.mockito.Mockito.spy;
+import static org.robolectric.Shadows.shadowOf;
+
+import android.os.Process;
+
+import com.android.launcher3.AppInfo;
+import com.android.launcher3.ItemInfo;
+import com.android.launcher3.PagedView;
+import com.android.launcher3.model.BgDataModel.Callbacks;
+import com.android.launcher3.util.Executors;
+import com.android.launcher3.util.LauncherLayoutBuilder;
+import com.android.launcher3.util.LauncherModelHelper;
+import com.android.launcher3.util.LauncherRoboTestRunner;
+import com.android.launcher3.util.LooperExecutor;
+import com.android.launcher3.util.ViewOnDrawExecutor;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.robolectric.RuntimeEnvironment;
+import org.robolectric.annotation.LooperMode;
+import org.robolectric.annotation.LooperMode.Mode;
+import org.robolectric.shadows.ShadowPackageManager;
+import org.robolectric.util.ReflectionHelpers;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.HashSet;
+import java.util.List;
+import java.util.stream.Collectors;
+
+/**
+ * Tests to verify multiple callbacks in Loader
+ */
+@RunWith(LauncherRoboTestRunner.class)
+@LooperMode(Mode.PAUSED)
+public class ModelMultiCallbacksTest {
+
+    private LauncherModelHelper mModelHelper;
+
+    private ShadowPackageManager mSpm;
+    private LooperExecutor mTempMainExecutor;
+
+    @Before
+    public void setUp() throws Exception {
+        mModelHelper = new LauncherModelHelper();
+        mModelHelper.installApp(TEST_PACKAGE);
+
+        mSpm = shadowOf(RuntimeEnvironment.application.getPackageManager());
+
+        // Since robolectric tests run on main thread, we run the loader-UI calls on a temp thread,
+        // so that we can wait appropriately for the loader to complete.
+        mTempMainExecutor = new LooperExecutor(createAndStartNewForegroundLooper("tempMain"));
+        ReflectionHelpers.setField(mModelHelper.getModel(), "mMainExecutor", mTempMainExecutor);
+    }
+
+    @Test
+    public void testTwoCallbacks_loadedTogether() throws Exception {
+        setupWorkspacePages(3);
+
+        MyCallbacks cb1 = spy(MyCallbacks.class);
+        mModelHelper.getModel().addCallbacksAndLoad(cb1);
+
+        waitForLoaderAndTempMainThread();
+        cb1.verifySynchronouslyBound(3);
+
+        // Add a new callback
+        cb1.reset();
+        MyCallbacks cb2 = spy(MyCallbacks.class);
+        cb2.mPageToBindSync = 2;
+        mModelHelper.getModel().addCallbacksAndLoad(cb2);
+
+        waitForLoaderAndTempMainThread();
+        cb1.verifySynchronouslyBound(3);
+        cb2.verifySynchronouslyBound(3);
+
+        // Remove callbacks
+        cb1.reset();
+        cb2.reset();
+
+        // No effect on callbacks when removing an callback
+        mModelHelper.getModel().removeCallbacks(cb2);
+        waitForLoaderAndTempMainThread();
+        assertNull(cb1.mDeferredExecutor);
+        assertNull(cb2.mDeferredExecutor);
+
+        // Reloading only loads registered callbacks
+        mModelHelper.getModel().startLoader();
+        waitForLoaderAndTempMainThread();
+        cb1.verifySynchronouslyBound(3);
+        assertNull(cb2.mDeferredExecutor);
+    }
+
+    @Test
+    public void testTwoCallbacks_receiveUpdates() throws Exception {
+        setupWorkspacePages(1);
+
+        MyCallbacks cb1 = spy(MyCallbacks.class);
+        MyCallbacks cb2 = spy(MyCallbacks.class);
+        mModelHelper.getModel().addCallbacksAndLoad(cb1);
+        mModelHelper.getModel().addCallbacksAndLoad(cb2);
+        waitForLoaderAndTempMainThread();
+
+        cb1.verifyApps(TEST_PACKAGE);
+        cb2.verifyApps(TEST_PACKAGE);
+
+        // Install package 1
+        String pkg1 = "com.test.pkg1";
+        mModelHelper.installApp(pkg1);
+        mModelHelper.getModel().onPackageAdded(pkg1, Process.myUserHandle());
+        waitForLoaderAndTempMainThread();
+        cb1.verifyApps(TEST_PACKAGE, pkg1);
+        cb2.verifyApps(TEST_PACKAGE, pkg1);
+
+        // Install package 2
+        String pkg2 = "com.test.pkg2";
+        mModelHelper.installApp(pkg2);
+        mModelHelper.getModel().onPackageAdded(pkg2, Process.myUserHandle());
+        waitForLoaderAndTempMainThread();
+        cb1.verifyApps(TEST_PACKAGE, pkg1, pkg2);
+        cb2.verifyApps(TEST_PACKAGE, pkg1, pkg2);
+
+        // Uninstall package 2
+        mSpm.removePackage(pkg1);
+        mModelHelper.getModel().onPackageRemoved(pkg1, Process.myUserHandle());
+        waitForLoaderAndTempMainThread();
+        cb1.verifyApps(TEST_PACKAGE, pkg2);
+        cb2.verifyApps(TEST_PACKAGE, pkg2);
+
+        // Unregister a callback and verify updates no longer received
+        mModelHelper.getModel().removeCallbacks(cb2);
+        mSpm.removePackage(pkg2);
+        mModelHelper.getModel().onPackageRemoved(pkg2, Process.myUserHandle());
+        waitForLoaderAndTempMainThread();
+        cb1.verifyApps(TEST_PACKAGE);
+        cb2.verifyApps(TEST_PACKAGE, pkg2);
+    }
+
+    private void waitForLoaderAndTempMainThread() throws Exception {
+        Executors.MODEL_EXECUTOR.submit(() -> { }).get();
+        mTempMainExecutor.submit(() -> { }).get();
+    }
+
+    private void setupWorkspacePages(int pageCount) throws Exception {
+        // Create a layout with 3 pages
+        LauncherLayoutBuilder builder = new LauncherLayoutBuilder();
+        for (int i = 0; i < pageCount; i++) {
+            builder.atWorkspace(1, 1, i).putApp(TEST_PACKAGE, TEST_PACKAGE);
+        }
+        mModelHelper.setupDefaultLayoutProvider(builder);
+    }
+
+    private abstract static class MyCallbacks implements Callbacks {
+
+        final List<ItemInfo> mItems = new ArrayList<>();
+        int mPageToBindSync = 0;
+        int mPageBoundSync = PagedView.INVALID_PAGE;
+        ViewOnDrawExecutor mDeferredExecutor;
+        AppInfo[] mAppInfos;
+
+        MyCallbacks() { }
+
+        @Override
+        public void onPageBoundSynchronously(int page) {
+            mPageBoundSync = page;
+        }
+
+        @Override
+        public void executeOnNextDraw(ViewOnDrawExecutor executor) {
+            mDeferredExecutor = executor;
+        }
+
+        @Override
+        public void bindItems(List<ItemInfo> shortcuts, boolean forceAnimateIcons) {
+            mItems.addAll(shortcuts);
+        }
+
+        @Override
+        public void bindAllApplications(AppInfo[] apps) {
+            mAppInfos = apps;
+        }
+
+        @Override
+        public int getPageToBindSynchronously() {
+            return mPageToBindSync;
+        }
+
+        public void reset() {
+            mItems.clear();
+            mPageBoundSync = PagedView.INVALID_PAGE;
+            mDeferredExecutor = null;
+            mAppInfos = null;
+        }
+
+        public void verifySynchronouslyBound(int totalItems) {
+            // Verify that the requested page is bound synchronously
+            assertEquals(mPageBoundSync, mPageToBindSync);
+            assertEquals(mItems.size(), 1);
+            assertEquals(mItems.get(0).screenId, mPageBoundSync);
+            assertNotNull(mDeferredExecutor);
+
+            // Verify that all other pages are bound properly
+            mDeferredExecutor.runAllTasks();
+            assertEquals(mItems.size(), totalItems);
+        }
+
+        public void verifyApps(String... apps) {
+            assertEquals(apps.length, mAppInfos.length);
+            assertEquals(Arrays.stream(mAppInfos)
+                    .map(ai -> ai.getTargetComponent().getPackageName())
+                    .collect(Collectors.toSet()),
+                    new HashSet<>(Arrays.asList(apps)));
+        }
+    }
+}
diff --git a/robolectric_tests/src/com/android/launcher3/shadows/LShadowLauncherApps.java b/robolectric_tests/src/com/android/launcher3/shadows/LShadowLauncherApps.java
index ccbc18a..166e28b 100644
--- a/robolectric_tests/src/com/android/launcher3/shadows/LShadowLauncherApps.java
+++ b/robolectric_tests/src/com/android/launcher3/shadows/LShadowLauncherApps.java
@@ -43,6 +43,7 @@
 
 import java.util.Collections;
 import java.util.List;
+import java.util.stream.Collectors;
 
 /**
  * Extension of {@link ShadowLauncherApps} with missing shadow methods
@@ -93,4 +94,26 @@
         return RuntimeEnvironment.application.getPackageManager()
                 .getApplicationInfo(packageName, flags);
     }
+
+    @Implementation
+    public List<LauncherActivityInfo> getActivityList(String packageName, UserHandle user) {
+        Intent intent = new Intent(Intent.ACTION_MAIN)
+                .addCategory(Intent.CATEGORY_LAUNCHER)
+                .setPackage(packageName);
+        return RuntimeEnvironment.application.getPackageManager().queryIntentActivities(intent, 0)
+                .stream()
+                .map(ri -> getLauncherActivityInfo(ri.activityInfo))
+                .collect(Collectors.toList());
+    }
+
+    @Implementation
+    public boolean hasShortcutHostPermission() {
+        return true;
+    }
+
+    @Override
+    protected List<LauncherActivityInfo> getShortcutConfigActivityList(String packageName,
+            UserHandle user) {
+        return Collections.emptyList();
+    }
 }
diff --git a/robolectric_tests/src/com/android/launcher3/util/LauncherModelHelper.java b/robolectric_tests/src/com/android/launcher3/util/LauncherModelHelper.java
index 1a03f9f..655055c 100644
--- a/robolectric_tests/src/com/android/launcher3/util/LauncherModelHelper.java
+++ b/robolectric_tests/src/com/android/launcher3/util/LauncherModelHelper.java
@@ -20,13 +20,19 @@
 import static org.mockito.Mockito.atLeast;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.verify;
+import static org.robolectric.Shadows.shadowOf;
 
 import android.content.ComponentName;
 import android.content.ContentValues;
 import android.content.Context;
 import android.content.Intent;
+import android.content.IntentFilter;
+import android.content.pm.PackageManager.NameNotFoundException;
+import android.net.Uri;
+import android.provider.Settings;
 
 import com.android.launcher3.AppInfo;
+import com.android.launcher3.InvariantDeviceProfile;
 import com.android.launcher3.ItemInfo;
 import com.android.launcher3.LauncherAppState;
 import com.android.launcher3.LauncherModel;
@@ -40,10 +46,14 @@
 import org.robolectric.Robolectric;
 import org.robolectric.RuntimeEnvironment;
 import org.robolectric.shadows.ShadowContentResolver;
+import org.robolectric.shadows.ShadowPackageManager;
 import org.robolectric.util.ReflectionHelpers;
 
 import java.io.BufferedReader;
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
 import java.io.InputStreamReader;
+import java.io.OutputStreamWriter;
 import java.lang.reflect.Field;
 import java.util.HashMap;
 import java.util.List;
@@ -63,6 +73,13 @@
     public static final int NO__ICON = -1;
     public static final String TEST_PACKAGE = "com.android.launcher3.validpackage";
 
+    // Authority for providing a dummy default-workspace-layout data.
+    private static final String TEST_PROVIDER_AUTHORITY =
+            LauncherModelHelper.class.getName().toLowerCase();
+    private static final int DEFAULT_BITMAP_SIZE = 10;
+    private static final int DEFAULT_GRID_SIZE = 4;
+
+
     private final HashMap<Class, HashMap<String, Field>> mFieldCache = new HashMap<>();
     public final TestLauncherProvider provider;
 
@@ -285,4 +302,42 @@
 
         return ids;
     }
+
+    /**
+     * Sets up a dummy provider to load the provided layout by default, next time the layout loads
+     */
+    public void setupDefaultLayoutProvider(LauncherLayoutBuilder builder) throws Exception {
+        Context context = RuntimeEnvironment.application;
+        InvariantDeviceProfile idp = InvariantDeviceProfile.INSTANCE.get(context);
+        idp.numRows = idp.numColumns = idp.numHotseatIcons = DEFAULT_GRID_SIZE;
+        idp.iconBitmapSize = DEFAULT_BITMAP_SIZE;
+
+        provider.setAllowLoadDefaultFavorites(true);
+        Settings.Secure.putString(context.getContentResolver(),
+                "launcher3.layout.provider", TEST_PROVIDER_AUTHORITY);
+
+        shadowOf(context.getPackageManager())
+                .addProviderIfNotPresent(new ComponentName("com.test", "Dummy")).authority =
+                TEST_PROVIDER_AUTHORITY;
+
+        ByteArrayOutputStream bos = new ByteArrayOutputStream();
+        builder.build(new OutputStreamWriter(bos));
+        Uri layoutUri = LauncherProvider.getLayoutUri(TEST_PROVIDER_AUTHORITY, context);
+        shadowOf(context.getContentResolver()).registerInputStream(layoutUri,
+                new ByteArrayInputStream(bos.toByteArray()));
+    }
+
+    /**
+     * Simulates an apk install with a default main activity with same class and package name
+     */
+    public void installApp(String component) throws NameNotFoundException {
+        ShadowPackageManager spm = shadowOf(RuntimeEnvironment.application.getPackageManager());
+        ComponentName cn = new ComponentName(component, component);
+        spm.addActivityIfNotPresent(cn);
+
+        IntentFilter filter = new IntentFilter(Intent.ACTION_MAIN);
+        filter.addCategory(Intent.CATEGORY_LAUNCHER);
+        filter.addCategory(Intent.CATEGORY_DEFAULT);
+        spm.addIntentFilterForActivity(cn, filter);
+    }
 }
diff --git a/src/com/android/launcher3/DeleteDropTarget.java b/src/com/android/launcher3/DeleteDropTarget.java
index bd48aec..423f2bb 100644
--- a/src/com/android/launcher3/DeleteDropTarget.java
+++ b/src/com/android/launcher3/DeleteDropTarget.java
@@ -126,7 +126,8 @@
             onAccessibilityDrop(null, item);
             ModelWriter modelWriter = mLauncher.getModelWriter();
             Runnable onUndoClicked = () -> {
-                modelWriter.abortDelete(itemPage);
+                mLauncher.setPageToBindSynchronously(itemPage);
+                modelWriter.abortDelete();
                 mLauncher.getUserEventDispatcher().logActionOnControl(TAP, UNDO);
             };
             Snackbar.show(mLauncher, R.string.item_removed, R.string.undo,
diff --git a/src/com/android/launcher3/Launcher.java b/src/com/android/launcher3/Launcher.java
index a7bb9ee..f5fafbf 100644
--- a/src/com/android/launcher3/Launcher.java
+++ b/src/com/android/launcher3/Launcher.java
@@ -292,6 +292,7 @@
     private PopupDataProvider mPopupDataProvider;
 
     private int mSynchronouslyBoundPage = PagedView.INVALID_PAGE;
+    private int mPageToBindSynchronously = PagedView.INVALID_PAGE;
 
     // We only want to get the SharedPreferences once since it does an FS stat each time we get
     // it from the context.
@@ -348,7 +349,7 @@
 
         LauncherAppState app = LauncherAppState.getInstance(this);
         mOldConfig = new Configuration(getResources().getConfiguration());
-        mModel = app.setLauncher(this);
+        mModel = app.getModel();
         mRotationHelper = new RotationHelper(this);
         InvariantDeviceProfile idp = app.getInvariantDeviceProfile();
         initDeviceProfile(idp);
@@ -386,22 +387,18 @@
 
         // We only load the page synchronously if the user rotates (or triggers a
         // configuration change) while launcher is in the foreground
-        int currentScreen = PagedView.INVALID_RESTORE_PAGE;
+        int currentScreen = PagedView.INVALID_PAGE;
         if (savedInstanceState != null) {
             currentScreen = savedInstanceState.getInt(RUNTIME_STATE_CURRENT_SCREEN, currentScreen);
         }
+        mPageToBindSynchronously = currentScreen;
 
-        if (!mModel.startLoader(currentScreen)) {
+        if (!mModel.addCallbacksAndLoad(this)) {
             if (!internalStateHandled) {
                 // If we are not binding synchronously, show a fade in animation when
                 // the first page bind completes.
                 mDragLayer.getAlphaProperty(ALPHA_INDEX_LAUNCHER_LOAD).setValue(0);
             }
-        } else {
-            // Pages bound synchronously.
-            mWorkspace.setCurrentPage(currentScreen);
-
-            setWorkspaceLoading(true);
         }
 
         // For handling default keys
@@ -522,15 +519,6 @@
     }
 
     @Override
-    public void rebindModel() {
-        int currentPage = mWorkspace.getNextPage();
-        if (mModel.startLoader(currentPage)) {
-            mWorkspace.setCurrentPage(currentPage);
-            setWorkspaceLoading(true);
-        }
-    }
-
-    @Override
     public void onIdpChanged(int changeFlags, InvariantDeviceProfile idp) {
         onIdpChanged(idp);
     }
@@ -548,7 +536,7 @@
         // initialized properly.
         onSaveInstanceState(new Bundle());
         if (oldWallpaperProfile != getWallpaperDeviceProfile()) {
-            rebindModel();
+            mModel.rebindCallbacks();
         }
     }
 
@@ -1543,13 +1531,7 @@
         mWorkspace.removeFolderListeners();
         PluginManagerWrapper.INSTANCE.get(this).removePluginListener(this);
 
-        // Stop callbacks from LauncherModel
-        // It's possible to receive onDestroy after a new Launcher activity has
-        // been created. In this case, don't interfere with the new Launcher.
-        if (mModel.isCurrentCallbacks(this)) {
-            mModel.stopLoader();
-            LauncherAppState.getInstance(this).setLauncher(null);
-        }
+        mModel.removeCallbacks(this);
         mRotationHelper.destroy();
 
         try {
@@ -1957,11 +1939,21 @@
     }
 
     /**
+     * Sets the next page to bind synchronously on next bind.
+     * @param page
+     */
+    public void setPageToBindSynchronously(int page) {
+        mPageToBindSynchronously = page;
+    }
+
+    /**
      * Implementation of the method from LauncherModel.Callbacks.
      */
     @Override
-    public int getCurrentWorkspaceScreen() {
-        if (mWorkspace != null) {
+    public int getPageToBindSynchronously() {
+        if (mPageToBindSynchronously != PagedView.INVALID_PAGE) {
+            return mPageToBindSynchronously;
+        } else  if (mWorkspace != null) {
             return mWorkspace.getCurrentPage();
         } else {
             return 0;
@@ -2339,6 +2331,8 @@
 
     public void onPageBoundSynchronously(int page) {
         mSynchronouslyBoundPage = page;
+        mWorkspace.setCurrentPage(page);
+        mPageToBindSynchronously = PagedView.INVALID_PAGE;
     }
 
     @Override
@@ -2403,6 +2397,7 @@
         // Since we are just resetting the current page without user interaction,
         // override the previous page so we don't log the page switch.
         mWorkspace.setCurrentPage(pageBoundFirst, pageBoundFirst /* overridePrevPage */);
+        mPageToBindSynchronously = PagedView.INVALID_PAGE;
 
         // Cache one page worth of icons
         getViewCache().setCacheSize(R.layout.folder_application,
diff --git a/src/com/android/launcher3/LauncherAppState.java b/src/com/android/launcher3/LauncherAppState.java
index c6946ca..4cd038d 100644
--- a/src/com/android/launcher3/LauncherAppState.java
+++ b/src/com/android/launcher3/LauncherAppState.java
@@ -160,11 +160,6 @@
         }
     }
 
-    LauncherModel setLauncher(Launcher launcher) {
-        mModel.initialize(launcher);
-        return mModel;
-    }
-
     public IconCache getIconCache() {
         return mIconCache;
     }
diff --git a/src/com/android/launcher3/LauncherModel.java b/src/com/android/launcher3/LauncherModel.java
index 63b0e1e..cf978b5 100644
--- a/src/com/android/launcher3/LauncherModel.java
+++ b/src/com/android/launcher3/LauncherModel.java
@@ -16,6 +16,12 @@
 
 package com.android.launcher3;
 
+import static com.android.launcher3.LauncherAppState.ACTION_FORCE_ROLOAD;
+import static com.android.launcher3.config.FeatureFlags.IS_DOGFOOD_BUILD;
+import static com.android.launcher3.util.Executors.MAIN_EXECUTOR;
+import static com.android.launcher3.util.Executors.MODEL_EXECUTOR;
+import static com.android.launcher3.util.PackageManagerHelper.hasShortcutsPermission;
+
 import android.content.Context;
 import android.content.Intent;
 import android.content.pm.LauncherApps;
@@ -52,13 +58,12 @@
 import com.android.launcher3.shortcuts.ShortcutRequest;
 import com.android.launcher3.util.IntSparseArrayMap;
 import com.android.launcher3.util.ItemInfoMatcher;
+import com.android.launcher3.util.LooperExecutor;
 import com.android.launcher3.util.PackageUserKey;
 import com.android.launcher3.util.Preconditions;
-import com.android.launcher3.util.Thunk;
 
 import java.io.FileDescriptor;
 import java.io.PrintWriter;
-import java.lang.ref.WeakReference;
 import java.util.ArrayList;
 import java.util.HashSet;
 import java.util.List;
@@ -67,12 +72,6 @@
 import java.util.concurrent.Executor;
 import java.util.function.Supplier;
 
-import static com.android.launcher3.LauncherAppState.ACTION_FORCE_ROLOAD;
-import static com.android.launcher3.config.FeatureFlags.IS_DOGFOOD_BUILD;
-import static com.android.launcher3.util.Executors.MAIN_EXECUTOR;
-import static com.android.launcher3.util.Executors.MODEL_EXECUTOR;
-import static com.android.launcher3.util.PackageManagerHelper.hasShortcutsPermission;
-
 /**
  * Maintains in-memory state of the Launcher. It is expected that there should be only one
  * LauncherModel object held in a static. Also provide APIs for updating the database state
@@ -83,11 +82,12 @@
 
     static final String TAG = "Launcher.Model";
 
-    @Thunk final LauncherAppState mApp;
-    @Thunk final Object mLock = new Object();
-    @Thunk
-    LoaderTask mLoaderTask;
-    @Thunk boolean mIsLoaderTaskRunning;
+    private final LauncherAppState mApp;
+    private final Object mLock = new Object();
+    private final LooperExecutor mMainExecutor = MAIN_EXECUTOR;
+
+    private LoaderTask mLoaderTask;
+    private boolean mIsLoaderTaskRunning;
 
     // Indicates whether the current model data is valid or not.
     // We start off with everything not loaded. After that, we assume that
@@ -100,7 +100,7 @@
         }
     }
 
-    @Thunk WeakReference<Callbacks> mCallbacks;
+    private final ArrayList<Callbacks> mCallbacksList = new ArrayList<>(1);
 
     // < only access in worker thread >
     private final AllAppsList mBgAllAppsList;
@@ -141,9 +141,8 @@
      * Adds the provided items to the workspace.
      */
     public void addAndBindAddedWorkspaceItems(List<Pair<ItemInfo, Object>> itemList) {
-        Callbacks callbacks = getCallback();
-        if (callbacks != null) {
-            callbacks.preAddApps();
+        for (Callbacks cb : getCallbacks()) {
+            cb.preAddApps();
         }
         enqueueModelUpdateTask(new AddWorkspaceItemsTask(itemList));
     }
@@ -153,16 +152,6 @@
                 hasVerticalHotseat, verifyChanges);
     }
 
-    /**
-     * Set this as the current Launcher activity object for the loader.
-     */
-    public void initialize(Callbacks callbacks) {
-        synchronized (mLock) {
-            Preconditions.assertUIThread();
-            mCallbacks = new WeakReference<>(callbacks);
-        }
-    }
-
     @Override
     public void onPackageChanged(String packageName, UserHandle user) {
         int op = PackageUpdatedTask.OP_UPDATE;
@@ -262,21 +251,19 @@
                 }
             }
         } else if (IS_DOGFOOD_BUILD && ACTION_FORCE_ROLOAD.equals(action)) {
-            Launcher l = (Launcher) getCallback();
-            l.reload();
+            for (Callbacks cb : getCallbacks()) {
+                if (cb instanceof Launcher) {
+                    ((Launcher) cb).recreate();
+                }
+            }
         }
     }
 
-    public void forceReload() {
-        forceReload(-1);
-    }
-
     /**
      * Reloads the workspace items from the DB and re-binds the workspace. This should generally
      * not be called as DB updates are automatically followed by UI update
-     * @param synchronousBindPage The page to bind first. Can pass -1 to use the current page.
      */
-    public void forceReload(int synchronousBindPage) {
+    public void forceReload() {
         synchronized (mLock) {
             // Stop any existing loaders first, so they don't set mModelLoaded to true later
             stopLoader();
@@ -285,37 +272,77 @@
 
         // Start the loader if launcher is already running, otherwise the loader will run,
         // the next time launcher starts
-        Callbacks callbacks = getCallback();
-        if (callbacks != null) {
-            if (synchronousBindPage < 0) {
-                synchronousBindPage = callbacks.getCurrentWorkspaceScreen();
-            }
-            startLoader(synchronousBindPage);
+        if (hasCallbacks()) {
+            startLoader();
         }
     }
 
-    public boolean isCurrentCallbacks(Callbacks callbacks) {
-        return (mCallbacks != null && mCallbacks.get() == callbacks);
+    /**
+     * Rebinds all existing callbacks with already loaded model
+     */
+    public void rebindCallbacks() {
+        if (hasCallbacks()) {
+            startLoader();
+        }
+    }
+
+    /**
+     * Removes an existing callback
+     */
+    public void removeCallbacks(Callbacks callbacks) {
+        synchronized (mCallbacksList) {
+            Preconditions.assertUIThread();
+            if (mCallbacksList.remove(callbacks)) {
+                if (stopLoader()) {
+                    // Rebind existing callbacks
+                    startLoader();
+                }
+            }
+        }
+    }
+
+    /**
+     * Adds a callbacks to receive model updates
+     * @return true if workspace load was performed synchronously
+     */
+    public boolean addCallbacksAndLoad(Callbacks callbacks) {
+        synchronized (mLock) {
+            addCallbacks(callbacks);
+            return startLoader();
+
+        }
+    }
+
+    /**
+     * Adds a callbacks to receive model updates
+     */
+    public void addCallbacks(Callbacks callbacks) {
+        Preconditions.assertUIThread();
+        synchronized (mCallbacksList) {
+            mCallbacksList.add(callbacks);
+        }
     }
 
     /**
      * Starts the loader. Tries to bind {@params synchronousBindPage} synchronously if possible.
      * @return true if the page could be bound synchronously.
      */
-    public boolean startLoader(int synchronousBindPage) {
+    public boolean startLoader() {
         // Enable queue before starting loader. It will get disabled in Launcher#finishBindingItems
         InstallShortcutReceiver.enableInstallQueue(InstallShortcutReceiver.FLAG_LOADER_RUNNING);
         synchronized (mLock) {
             // Don't bother to start the thread if we know it's not going to do anything
-            if (mCallbacks != null && mCallbacks.get() != null) {
-                final Callbacks oldCallbacks = mCallbacks.get();
+            final Callbacks[] callbacksList = getCallbacks();
+            if (callbacksList.length > 0) {
                 // Clear any pending bind-runnables from the synchronized load process.
-                MAIN_EXECUTOR.execute(oldCallbacks::clearPendingBinds);
+                for (Callbacks cb : callbacksList) {
+                    mMainExecutor.execute(cb::clearPendingBinds);
+                }
 
                 // If there is already one running, tell it to stop.
                 stopLoader();
-                LoaderResults loaderResults = new LoaderResults(mApp, mBgDataModel,
-                        mBgAllAppsList, synchronousBindPage, mCallbacks);
+                LoaderResults loaderResults = new LoaderResults(
+                        mApp, mBgDataModel, mBgAllAppsList, callbacksList, mMainExecutor);
                 if (mModelLoaded && !mIsLoaderTaskRunning) {
                     // Divide the set of loaded items into those that we are binding synchronously,
                     // and everything else that is to be bound normally (asynchronously).
@@ -336,14 +363,17 @@
 
     /**
      * If there is already a loader task running, tell it to stop.
+     * @return true if an existing loader was stopped.
      */
-    public void stopLoader() {
+    public boolean stopLoader() {
         synchronized (mLock) {
             LoaderTask oldTask = mLoaderTask;
             mLoaderTask = null;
             if (oldTask != null) {
                 oldTask.stopLocked();
+                return true;
             }
+            return false;
         }
     }
 
@@ -498,7 +528,7 @@
     }
 
     public void enqueueModelUpdateTask(ModelUpdateTask task) {
-        task.init(mApp, this, mBgDataModel, mBgAllAppsList, MAIN_EXECUTOR);
+        task.init(mApp, this, mBgDataModel, mBgAllAppsList, mMainExecutor);
         MODEL_EXECUTOR.execute(task);
     }
 
@@ -572,7 +602,21 @@
         mBgDataModel.dump(prefix, fd, writer, args);
     }
 
-    public Callbacks getCallback() {
-        return mCallbacks != null ? mCallbacks.get() : null;
+    /**
+     * Returns true if there are any callbacks attached to the model
+     */
+    public boolean hasCallbacks() {
+        synchronized (mCallbacksList) {
+            return !mCallbacksList.isEmpty();
+        }
+    }
+
+    /**
+     * Returns an array of currently attached callbacks
+     */
+    public Callbacks[] getCallbacks() {
+        synchronized (mCallbacksList) {
+            return mCallbacksList.toArray(new Callbacks[mCallbacksList.size()]);
+        }
     }
 }
diff --git a/src/com/android/launcher3/PagedView.java b/src/com/android/launcher3/PagedView.java
index ff2b400..a1888bf 100644
--- a/src/com/android/launcher3/PagedView.java
+++ b/src/com/android/launcher3/PagedView.java
@@ -64,7 +64,7 @@
     private static final String TAG = "PagedView";
     private static final boolean DEBUG = false;
 
-    protected static final int INVALID_PAGE = -1;
+    public static final int INVALID_PAGE = -1;
     protected static final ComputePageScrollsLogic SIMPLE_SCROLL_LOGIC = (v) -> v.getVisibility() != GONE;
 
     public static final int PAGE_SNAP_ANIMATION_DURATION = 750;
@@ -84,8 +84,6 @@
     private static final int MIN_SNAP_VELOCITY = 1500;
     private static final int MIN_FLING_VELOCITY = 250;
 
-    public static final int INVALID_RESTORE_PAGE = -1001;
-
     private boolean mFreeScroll = false;
 
     protected int mFlingThresholdVelocity;
diff --git a/src/com/android/launcher3/graphics/LauncherPreviewRenderer.java b/src/com/android/launcher3/graphics/LauncherPreviewRenderer.java
index bfe7351..def76e8 100644
--- a/src/com/android/launcher3/graphics/LauncherPreviewRenderer.java
+++ b/src/com/android/launcher3/graphics/LauncherPreviewRenderer.java
@@ -70,6 +70,7 @@
 import com.android.launcher3.icons.BitmapRenderer;
 import com.android.launcher3.model.AllAppsList;
 import com.android.launcher3.model.BgDataModel;
+import com.android.launcher3.model.BgDataModel.Callbacks;
 import com.android.launcher3.model.LoaderResults;
 import com.android.launcher3.views.ActivityContext;
 import com.android.launcher3.views.BaseDragLayer;
@@ -377,7 +378,7 @@
             if (!mModel.isModelLoaded()) {
                 Log.d(TAG, "Workspace not loaded, loading now");
                 mModel.startLoaderForResults(
-                        new LoaderResults(mApp, mBgDataModel, mAllAppsList, 0, null));
+                        new LoaderResults(mApp, mBgDataModel, mAllAppsList, new Callbacks[0]));
                 return new ArrayList<>();
             }
             return mBgDataModel.workspaceItems;
diff --git a/src/com/android/launcher3/model/BaseLoaderResults.java b/src/com/android/launcher3/model/BaseLoaderResults.java
index 76c2951..0d12183 100644
--- a/src/com/android/launcher3/model/BaseLoaderResults.java
+++ b/src/com/android/launcher3/model/BaseLoaderResults.java
@@ -18,9 +18,7 @@
 
 import static com.android.launcher3.model.ModelUtils.filterCurrentWorkspaceItems;
 import static com.android.launcher3.model.ModelUtils.sortWorkspaceItemsSpatially;
-import static com.android.launcher3.util.Executors.MAIN_EXECUTOR;
 
-import android.os.Looper;
 import android.util.Log;
 
 import com.android.launcher3.AppInfo;
@@ -32,12 +30,13 @@
 import com.android.launcher3.PagedView;
 import com.android.launcher3.model.BgDataModel.Callbacks;
 import com.android.launcher3.util.IntArray;
+import com.android.launcher3.util.LooperExecutor;
 import com.android.launcher3.util.LooperIdleLock;
 import com.android.launcher3.util.ViewOnDrawExecutor;
 
-import java.lang.ref.WeakReference;
 import java.util.ArrayList;
 import java.util.Collections;
+import java.util.List;
 import java.util.concurrent.Executor;
 
 /**
@@ -49,40 +48,29 @@
     protected static final int INVALID_SCREEN_ID = -1;
     private static final int ITEMS_CHUNK = 6; // batch size for the workspace icons
 
-    protected final Executor mUiExecutor;
+    protected final LooperExecutor mUiExecutor;
 
     protected final LauncherAppState mApp;
     protected final BgDataModel mBgDataModel;
     private final AllAppsList mBgAllAppsList;
-    protected final int mPageToBindFirst;
 
-    protected final WeakReference<Callbacks> mCallbacks;
+    private final Callbacks[] mCallbacksList;
 
     private int mMyBindingId;
 
     public BaseLoaderResults(LauncherAppState app, BgDataModel dataModel,
-            AllAppsList allAppsList, int pageToBindFirst, WeakReference<Callbacks> callbacks) {
-        mUiExecutor = MAIN_EXECUTOR;
+            AllAppsList allAppsList, Callbacks[] callbacksList, LooperExecutor uiExecutor) {
+        mUiExecutor = uiExecutor;
         mApp = app;
         mBgDataModel = dataModel;
         mBgAllAppsList = allAppsList;
-        mPageToBindFirst = pageToBindFirst;
-        mCallbacks = callbacks == null ? new WeakReference<>(null) : callbacks;
+        mCallbacksList = callbacksList;
     }
 
     /**
      * Binds all loaded data to actual views on the main thread.
      */
     public void bindWorkspace() {
-        Callbacks callbacks = mCallbacks.get();
-        // Don't use these two variables in any of the callback runnables.
-        // Otherwise we hold a reference to them.
-        if (callbacks == null) {
-            // This launcher has exited and nobody bothered to tell us.  Just bail.
-            Log.w(TAG, "LoaderTask running with no launcher");
-            return;
-        }
-
         // Save a copy of all the bg-thread collections
         ArrayList<ItemInfo> workspaceItems = new ArrayList<>();
         ArrayList<LauncherAppWidgetInfo> appWidgets = new ArrayList<>();
@@ -96,97 +84,9 @@
             mMyBindingId = mBgDataModel.lastBindId;
         }
 
-        final int currentScreen;
-        {
-            int currScreen = mPageToBindFirst != PagedView.INVALID_RESTORE_PAGE
-                    ? mPageToBindFirst : callbacks.getCurrentWorkspaceScreen();
-            if (currScreen >= orderedScreenIds.size()) {
-                // There may be no workspace screens (just hotseat items and an empty page).
-                currScreen = PagedView.INVALID_RESTORE_PAGE;
-            }
-            currentScreen = currScreen;
-        }
-        final boolean validFirstPage = currentScreen >= 0;
-        final int currentScreenId =
-                validFirstPage ? orderedScreenIds.get(currentScreen) : INVALID_SCREEN_ID;
-
-        // Separate the items that are on the current screen, and all the other remaining items
-        ArrayList<ItemInfo> currentWorkspaceItems = new ArrayList<>();
-        ArrayList<ItemInfo> otherWorkspaceItems = new ArrayList<>();
-        ArrayList<LauncherAppWidgetInfo> currentAppWidgets = new ArrayList<>();
-        ArrayList<LauncherAppWidgetInfo> otherAppWidgets = new ArrayList<>();
-
-        filterCurrentWorkspaceItems(currentScreenId, workspaceItems, currentWorkspaceItems,
-                otherWorkspaceItems);
-        filterCurrentWorkspaceItems(currentScreenId, appWidgets, currentAppWidgets,
-                otherAppWidgets);
-        final InvariantDeviceProfile idp = mApp.getInvariantDeviceProfile();
-        sortWorkspaceItemsSpatially(idp, currentWorkspaceItems);
-        sortWorkspaceItemsSpatially(idp, otherWorkspaceItems);
-
-        // Tell the workspace that we're about to start binding items
-        executeCallbacksTask(c -> {
-            c.clearPendingBinds();
-            c.startBinding();
-        }, mUiExecutor);
-
-        // Bind workspace screens
-        executeCallbacksTask(c -> c.bindScreens(orderedScreenIds), mUiExecutor);
-
-        Executor mainExecutor = mUiExecutor;
-        // Load items on the current page.
-        bindWorkspaceItems(currentWorkspaceItems, mainExecutor);
-        bindAppWidgets(currentAppWidgets, mainExecutor);
-        // In case of validFirstPage, only bind the first screen, and defer binding the
-        // remaining screens after first onDraw (and an optional the fade animation whichever
-        // happens later).
-        // This ensures that the first screen is immediately visible (eg. during rotation)
-        // In case of !validFirstPage, bind all pages one after other.
-        final Executor deferredExecutor =
-                validFirstPage ? new ViewOnDrawExecutor() : mainExecutor;
-
-        executeCallbacksTask(c -> c.finishFirstPageBind(
-                validFirstPage ? (ViewOnDrawExecutor) deferredExecutor : null), mainExecutor);
-
-        bindWorkspaceItems(otherWorkspaceItems, deferredExecutor);
-        bindAppWidgets(otherAppWidgets, deferredExecutor);
-        // Tell the workspace that we're done binding items
-        executeCallbacksTask(c -> c.finishBindingItems(mPageToBindFirst), deferredExecutor);
-
-        if (validFirstPage) {
-            executeCallbacksTask(c -> {
-                // We are loading synchronously, which means, some of the pages will be
-                // bound after first draw. Inform the callbacks that page binding is
-                // not complete, and schedule the remaining pages.
-                if (currentScreen != PagedView.INVALID_RESTORE_PAGE) {
-                    c.onPageBoundSynchronously(currentScreen);
-                }
-                c.executeOnNextDraw((ViewOnDrawExecutor) deferredExecutor);
-
-            }, mUiExecutor);
-        }
-    }
-
-    protected void bindWorkspaceItems(final ArrayList<ItemInfo> workspaceItems,
-            final Executor executor) {
-        // Bind the workspace items
-        int N = workspaceItems.size();
-        for (int i = 0; i < N; i += ITEMS_CHUNK) {
-            final int start = i;
-            final int chunkSize = (i+ITEMS_CHUNK <= N) ? ITEMS_CHUNK : (N-i);
-            executeCallbacksTask(
-                    c -> c.bindItems(workspaceItems.subList(start, start + chunkSize), false),
-                    executor);
-        }
-    }
-
-    private void bindAppWidgets(ArrayList<LauncherAppWidgetInfo> appWidgets, Executor executor) {
-        int N;// Bind the widgets, one at a time
-        N = appWidgets.size();
-        for (int i = 0; i < N; i++) {
-            final ItemInfo widget = appWidgets.get(i);
-            executeCallbacksTask(
-                    c -> c.bindItems(Collections.singletonList(widget), false), executor);
+        for (Callbacks cb : mCallbacksList) {
+            new WorkspaceBinder(cb, mUiExecutor, mApp, mBgDataModel, mMyBindingId,
+                    workspaceItems, appWidgets, orderedScreenIds).bind();
         }
     }
 
@@ -206,19 +106,155 @@
                 Log.d(TAG, "Too many consecutive reloads, skipping obsolete data-bind");
                 return;
             }
-            Callbacks callbacks = mCallbacks.get();
-            if (callbacks != null) {
-                task.execute(callbacks);
+            for (Callbacks cb : mCallbacksList) {
+                task.execute(cb);
             }
         });
     }
 
     public LooperIdleLock newIdleLock(Object lock) {
-        LooperIdleLock idleLock = new LooperIdleLock(lock, Looper.getMainLooper());
+        LooperIdleLock idleLock = new LooperIdleLock(lock, mUiExecutor.getLooper());
         // If we are not binding or if the main looper is already idle, there is no reason to wait
-        if (mCallbacks.get() == null || Looper.getMainLooper().getQueue().isIdle()) {
+        if (mUiExecutor.getLooper().getQueue().isIdle()) {
             idleLock.queueIdle();
         }
         return idleLock;
     }
+
+    private static class WorkspaceBinder {
+
+        private final Executor mUiExecutor;
+        private final Callbacks mCallbacks;
+
+        private final LauncherAppState mApp;
+        private final BgDataModel mBgDataModel;
+
+        private final int mMyBindingId;
+        private final ArrayList<ItemInfo> mWorkspaceItems;
+        private final ArrayList<LauncherAppWidgetInfo> mAppWidgets;
+        private final IntArray mOrderedScreenIds;
+
+
+        WorkspaceBinder(Callbacks callbacks,
+                Executor uiExecutor,
+                LauncherAppState app,
+                BgDataModel bgDataModel,
+                int myBindingId,
+                ArrayList<ItemInfo> workspaceItems,
+                ArrayList<LauncherAppWidgetInfo> appWidgets,
+                IntArray orderedScreenIds) {
+            mCallbacks = callbacks;
+            mUiExecutor = uiExecutor;
+            mApp = app;
+            mBgDataModel = bgDataModel;
+            mMyBindingId = myBindingId;
+            mWorkspaceItems = workspaceItems;
+            mAppWidgets = appWidgets;
+            mOrderedScreenIds = orderedScreenIds;
+        }
+
+        private void bind() {
+            final int currentScreen;
+            {
+                // Create an anonymous scope to calculate currentScreen as it has to be a
+                // final variable.
+                int currScreen = mCallbacks.getPageToBindSynchronously();
+                if (currScreen >= mOrderedScreenIds.size()) {
+                    // There may be no workspace screens (just hotseat items and an empty page).
+                    currScreen = PagedView.INVALID_PAGE;
+                }
+                currentScreen = currScreen;
+            }
+            final boolean validFirstPage = currentScreen >= 0;
+            final int currentScreenId =
+                    validFirstPage ? mOrderedScreenIds.get(currentScreen) : INVALID_SCREEN_ID;
+
+            // Separate the items that are on the current screen, and all the other remaining items
+            ArrayList<ItemInfo> currentWorkspaceItems = new ArrayList<>();
+            ArrayList<ItemInfo> otherWorkspaceItems = new ArrayList<>();
+            ArrayList<LauncherAppWidgetInfo> currentAppWidgets = new ArrayList<>();
+            ArrayList<LauncherAppWidgetInfo> otherAppWidgets = new ArrayList<>();
+
+            filterCurrentWorkspaceItems(currentScreenId, mWorkspaceItems, currentWorkspaceItems,
+                    otherWorkspaceItems);
+            filterCurrentWorkspaceItems(currentScreenId, mAppWidgets, currentAppWidgets,
+                    otherAppWidgets);
+            final InvariantDeviceProfile idp = mApp.getInvariantDeviceProfile();
+            sortWorkspaceItemsSpatially(idp, currentWorkspaceItems);
+            sortWorkspaceItemsSpatially(idp, otherWorkspaceItems);
+
+            // Tell the workspace that we're about to start binding items
+            executeCallbacksTask(c -> {
+                c.clearPendingBinds();
+                c.startBinding();
+            }, mUiExecutor);
+
+            // Bind workspace screens
+            executeCallbacksTask(c -> c.bindScreens(mOrderedScreenIds), mUiExecutor);
+
+            Executor mainExecutor = mUiExecutor;
+            // Load items on the current page.
+            bindWorkspaceItems(currentWorkspaceItems, mainExecutor);
+            bindAppWidgets(currentAppWidgets, mainExecutor);
+            // In case of validFirstPage, only bind the first screen, and defer binding the
+            // remaining screens after first onDraw (and an optional the fade animation whichever
+            // happens later).
+            // This ensures that the first screen is immediately visible (eg. during rotation)
+            // In case of !validFirstPage, bind all pages one after other.
+            final Executor deferredExecutor =
+                    validFirstPage ? new ViewOnDrawExecutor() : mainExecutor;
+
+            executeCallbacksTask(c -> c.finishFirstPageBind(
+                    validFirstPage ? (ViewOnDrawExecutor) deferredExecutor : null), mainExecutor);
+
+            bindWorkspaceItems(otherWorkspaceItems, deferredExecutor);
+            bindAppWidgets(otherAppWidgets, deferredExecutor);
+            // Tell the workspace that we're done binding items
+            executeCallbacksTask(c -> c.finishBindingItems(currentScreen), deferredExecutor);
+
+            if (validFirstPage) {
+                executeCallbacksTask(c -> {
+                    // We are loading synchronously, which means, some of the pages will be
+                    // bound after first draw. Inform the mCallbacks that page binding is
+                    // not complete, and schedule the remaining pages.
+                    c.onPageBoundSynchronously(currentScreen);
+                    c.executeOnNextDraw((ViewOnDrawExecutor) deferredExecutor);
+
+                }, mUiExecutor);
+            }
+        }
+
+        private void bindWorkspaceItems(
+                final ArrayList<ItemInfo> workspaceItems, final Executor executor) {
+            // Bind the workspace items
+            int count = workspaceItems.size();
+            for (int i = 0; i < count; i += ITEMS_CHUNK) {
+                final int start = i;
+                final int chunkSize = (i + ITEMS_CHUNK <= count) ? ITEMS_CHUNK : (count - i);
+                executeCallbacksTask(
+                        c -> c.bindItems(workspaceItems.subList(start, start + chunkSize), false),
+                        executor);
+            }
+        }
+
+        private void bindAppWidgets(List<LauncherAppWidgetInfo> appWidgets, Executor executor) {
+            // Bind the widgets, one at a time
+            int count = appWidgets.size();
+            for (int i = 0; i < count; i++) {
+                final ItemInfo widget = appWidgets.get(i);
+                executeCallbacksTask(
+                        c -> c.bindItems(Collections.singletonList(widget), false), executor);
+            }
+        }
+
+        protected void executeCallbacksTask(CallbackTask task, Executor executor) {
+            executor.execute(() -> {
+                if (mMyBindingId != mBgDataModel.lastBindId) {
+                    Log.d(TAG, "Too many consecutive reloads, skipping obsolete data-bind");
+                    return;
+                }
+                task.execute(mCallbacks);
+            });
+        }
+    }
 }
diff --git a/src/com/android/launcher3/model/BaseModelUpdateTask.java b/src/com/android/launcher3/model/BaseModelUpdateTask.java
index e12633b..5a7b4d3 100644
--- a/src/com/android/launcher3/model/BaseModelUpdateTask.java
+++ b/src/com/android/launcher3/model/BaseModelUpdateTask.java
@@ -20,17 +20,16 @@
 import com.android.launcher3.AppInfo;
 import com.android.launcher3.LauncherAppState;
 import com.android.launcher3.LauncherModel;
-import com.android.launcher3.LauncherModel.ModelUpdateTask;
 import com.android.launcher3.LauncherModel.CallbackTask;
-import com.android.launcher3.model.BgDataModel.Callbacks;
+import com.android.launcher3.LauncherModel.ModelUpdateTask;
 import com.android.launcher3.WorkspaceItemInfo;
+import com.android.launcher3.model.BgDataModel.Callbacks;
 import com.android.launcher3.util.ComponentKey;
 import com.android.launcher3.util.ItemInfoMatcher;
 import com.android.launcher3.widget.WidgetListRowEntry;
 
 import java.util.ArrayList;
 import java.util.HashMap;
-import java.util.List;
 import java.util.concurrent.Executor;
 
 /**
@@ -78,13 +77,9 @@
      * Schedules a {@param task} to be executed on the current callbacks.
      */
     public final void scheduleCallbackTask(final CallbackTask task) {
-        final Callbacks callbacks = mModel.getCallback();
-        mUiExecutor.execute(() -> {
-            Callbacks cb = mModel.getCallback();
-            if (callbacks == cb && cb != null) {
-                task.execute(callbacks);
-            }
-        });
+        for (final Callbacks cb : mModel.getCallbacks()) {
+            mUiExecutor.execute(() -> task.execute(cb));
+        }
     }
 
     public ModelWriter getModelWriter() {
diff --git a/src/com/android/launcher3/model/BgDataModel.java b/src/com/android/launcher3/model/BgDataModel.java
index 88f2a09..c24b939 100644
--- a/src/com/android/launcher3/model/BgDataModel.java
+++ b/src/com/android/launcher3/model/BgDataModel.java
@@ -436,9 +436,10 @@
     }
 
     public interface Callbacks {
-        void rebindModel();
-
-        int getCurrentWorkspaceScreen();
+        /**
+         * Returns the page number to bind first, synchronously if possible or -1
+         */
+        int getPageToBindSynchronously();
         void clearPendingBinds();
         void startBinding();
         void bindItems(List<ItemInfo> shortcuts, boolean forceAnimateIcons);
diff --git a/src/com/android/launcher3/model/ModelPreload.java b/src/com/android/launcher3/model/ModelPreload.java
index 2bd6cd4..713492b 100644
--- a/src/com/android/launcher3/model/ModelPreload.java
+++ b/src/com/android/launcher3/model/ModelPreload.java
@@ -18,14 +18,15 @@
 import android.content.Context;
 import android.util.Log;
 
+import androidx.annotation.WorkerThread;
+
 import com.android.launcher3.LauncherAppState;
 import com.android.launcher3.LauncherModel;
 import com.android.launcher3.LauncherModel.ModelUpdateTask;
+import com.android.launcher3.model.BgDataModel.Callbacks;
 
 import java.util.concurrent.Executor;
 
-import androidx.annotation.WorkerThread;
-
 /**
  * Utility class to preload LauncherModel
  */
@@ -50,7 +51,7 @@
     @Override
     public final void run() {
         mModel.startLoaderForResultsIfNotLoaded(
-                new LoaderResults(mApp, mBgDataModel, mAllAppsList, 0, null));
+                new LoaderResults(mApp, mBgDataModel, mAllAppsList, new Callbacks[0]));
         Log.d(TAG, "Preload completed : " + mModel.isModelLoaded());
         onComplete(mModel.isModelLoaded());
     }
diff --git a/src/com/android/launcher3/model/ModelWriter.java b/src/com/android/launcher3/model/ModelWriter.java
index bdf3a69..ccd1554 100644
--- a/src/com/android/launcher3/model/ModelWriter.java
+++ b/src/com/android/launcher3/model/ModelWriter.java
@@ -41,7 +41,6 @@
 import com.android.launcher3.WorkspaceItemInfo;
 import com.android.launcher3.config.FeatureFlags;
 import com.android.launcher3.logging.FileLog;
-import com.android.launcher3.model.BgDataModel.Callbacks;
 import com.android.launcher3.util.ContentWriter;
 import com.android.launcher3.util.ItemInfoMatcher;
 
@@ -350,12 +349,15 @@
         mDeleteRunnables.clear();
     }
 
-    public void abortDelete(int pageToBindFirst) {
+    /**
+     * Aborts a previous delete operation pending commit
+     */
+    public void abortDelete() {
         mPreparingToUndo = false;
         mDeleteRunnables.clear();
         // We do a full reload here instead of just a rebind because Folders change their internal
         // state when dragging an item out, which clobbers the rebind unless we load from the DB.
-        mModel.forceReload(pageToBindFirst);
+        mModel.forceReload();
     }
 
     private class UpdateItemRunnable extends UpdateItemBaseRunnable {
@@ -472,7 +474,7 @@
         }
 
         void verifyModel() {
-            if (!mVerifyChanges || mModel.getCallback() == null) {
+            if (!mVerifyChanges || !mModel.hasCallbacks()) {
                 return;
             }
 
@@ -488,11 +490,9 @@
                     // Bound model has not changed during the job
                     return;
                 }
+
                 // Bound model was changed between submitting the job and executing the job
-                Callbacks callbacks = mModel.getCallback();
-                if (callbacks != null) {
-                    callbacks.rebindModel();
-                }
+                mModel.rebindCallbacks();
             });
         }
     }
diff --git a/src/com/android/launcher3/util/ViewOnDrawExecutor.java b/src/com/android/launcher3/util/ViewOnDrawExecutor.java
index 5a131c8..451ae28 100644
--- a/src/com/android/launcher3/util/ViewOnDrawExecutor.java
+++ b/src/com/android/launcher3/util/ViewOnDrawExecutor.java
@@ -23,6 +23,8 @@
 import android.view.View.OnAttachStateChangeListener;
 import android.view.ViewTreeObserver.OnDrawListener;
 
+import androidx.annotation.VisibleForTesting;
+
 import com.android.launcher3.Launcher;
 
 import java.util.ArrayList;
@@ -118,7 +120,11 @@
         return mCompleted;
     }
 
-    protected void runAllTasks() {
+    /**
+     * Executes all tasks immediately
+     */
+    @VisibleForTesting
+    public void runAllTasks() {
         for (final Runnable r : mTasks) {
             r.run();
         }
diff --git a/src_shortcuts_overrides/com/android/launcher3/model/LoaderResults.java b/src_shortcuts_overrides/com/android/launcher3/model/LoaderResults.java
index 789bfd8..dcb4636 100644
--- a/src_shortcuts_overrides/com/android/launcher3/model/LoaderResults.java
+++ b/src_shortcuts_overrides/com/android/launcher3/model/LoaderResults.java
@@ -16,12 +16,14 @@
 
 package com.android.launcher3.model;
 
+import static com.android.launcher3.util.Executors.MAIN_EXECUTOR;
+
 import com.android.launcher3.LauncherAppState;
 import com.android.launcher3.model.BgDataModel.Callbacks;
 import com.android.launcher3.util.ComponentKey;
+import com.android.launcher3.util.LooperExecutor;
 import com.android.launcher3.widget.WidgetListRowEntry;
 
-import java.lang.ref.WeakReference;
 import java.util.ArrayList;
 import java.util.HashMap;
 
@@ -31,8 +33,13 @@
 public class LoaderResults extends BaseLoaderResults {
 
     public LoaderResults(LauncherAppState app, BgDataModel dataModel,
-            AllAppsList allAppsList, int pageToBindFirst, WeakReference<Callbacks> callbacks) {
-        super(app, dataModel, allAppsList, pageToBindFirst, callbacks);
+            AllAppsList allAppsList, Callbacks[] callbacks) {
+        this(app, dataModel, allAppsList, callbacks, MAIN_EXECUTOR);
+    }
+
+    public LoaderResults(LauncherAppState app, BgDataModel dataModel,
+            AllAppsList allAppsList, Callbacks[] callbacks, LooperExecutor executor) {
+        super(app, dataModel, allAppsList, callbacks, executor);
     }
 
     @Override