Merge "Add build variant for go-specific recents." into ub-launcher3-master
diff --git a/quickstep/src/com/android/quickstep/TaskListStabilizer.java b/quickstep/src/com/android/quickstep/TaskListStabilizer.java
index 0d23973..3eb26b4 100644
--- a/quickstep/src/com/android/quickstep/TaskListStabilizer.java
+++ b/quickstep/src/com/android/quickstep/TaskListStabilizer.java
@@ -17,79 +17,153 @@
 
 import static com.android.launcher3.config.FeatureFlags.ENABLE_TASK_STABILIZER;
 
+import android.app.ActivityManager.RecentTaskInfo;
+import android.content.ComponentName;
+import android.os.Process;
 import android.os.SystemClock;
-import android.util.SparseArray;
+import android.util.Log;
 
 import com.android.launcher3.util.IntArray;
-import com.android.launcher3.util.IntSet;
 import com.android.systemui.shared.recents.model.Task;
+import com.android.systemui.shared.recents.model.Task.TaskKey;
+import com.android.systemui.shared.system.ActivityManagerWrapper;
+import com.android.systemui.shared.system.TaskStackChangeListener;
 
 import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
 
 public class TaskListStabilizer {
 
     private static final long TASK_CACHE_TIMEOUT_MS = 5000;
 
-    private final SparseArray<Task> mTempMap = new SparseArray<>();
-    private final IntArray mTempArray = new IntArray();
-    private final IntSet mTempSet = new IntSet();
+    private static final int INVALID_TASK_ID = -1;
 
-    private final IntArray mLastStableOrder = new IntArray();
-    private final IntSet mLastSet = new IntSet();
-    private final IntArray mLastUnstableOrder = new IntArray();
+    private final TaskStackChangeListener mTaskStackListener = new TaskStackChangeListener() {
 
-    private long mLastReorderTime;
+        @Override
+        public void onTaskCreated(int taskId, ComponentName componentName) {
+            onTaskCreatedInternal(taskId);
+        }
 
-    public ArrayList<Task> reorder(ArrayList<Task> tasks) {
+        @Override
+        public void onTaskMovedToFront(int taskId) {
+            onTaskMovedToFrontInternal(taskId);
+        }
+
+        @Override
+        public void onTaskRemoved(int taskId) {
+            onTaskRemovedInternal(taskId);
+        }
+    };
+
+    // Task ids ordered based on recency, 0th index is the latest task
+    private final IntArray mOrderedTaskIds;
+
+    // Wrapper objects used for sorting tasks
+    private final ArrayList<TaskWrapper> mTaskWrappers = new ArrayList<>();
+
+    // Information about recent task re-order which has not been applied yet
+    private int mScheduledMoveTaskId = INVALID_TASK_ID;
+    private long mScheduledMoveTime = 0;
+
+    public TaskListStabilizer() {
+        if (ENABLE_TASK_STABILIZER.get()) {
+            // Initialize the task ids map
+            List<RecentTaskInfo> rawTasks = ActivityManagerWrapper.getInstance().getRecentTasks(
+                    Integer.MAX_VALUE, Process.myUserHandle().getIdentifier());
+            mOrderedTaskIds = new IntArray(rawTasks.size());
+            for (RecentTaskInfo info : rawTasks) {
+                mOrderedTaskIds.add(new TaskKey(info).id);
+            }
+
+            ActivityManagerWrapper.getInstance().registerTaskStackListener(mTaskStackListener);
+        } else {
+            mOrderedTaskIds = null;
+        }
+    }
+
+    private synchronized void onTaskCreatedInternal(int taskId) {
+        applyScheduledMoveUnchecked();
+        mOrderedTaskIds.add(taskId);
+    }
+
+    private synchronized void onTaskRemovedInternal(int taskId) {
+        applyScheduledMoveUnchecked();
+        mOrderedTaskIds.removeValue(taskId);
+    }
+
+    private void applyScheduledMoveUnchecked() {
+        if (mScheduledMoveTaskId != INVALID_TASK_ID) {
+            // Mode the scheduled task to front
+            mOrderedTaskIds.removeValue(mScheduledMoveTaskId);
+            mOrderedTaskIds.add(mScheduledMoveTaskId);
+            mScheduledMoveTaskId = INVALID_TASK_ID;
+        }
+    }
+
+    /**
+     * Checks if the scheduled move has timed out and moves the task to front accordingly.
+     */
+    private void applyScheduledMoveIfTime() {
+        if (mScheduledMoveTaskId != INVALID_TASK_ID
+                && (SystemClock.uptimeMillis() - mScheduledMoveTime) > TASK_CACHE_TIMEOUT_MS) {
+            applyScheduledMoveUnchecked();
+        }
+    }
+
+    private synchronized void onTaskMovedToFrontInternal(int taskId) {
+        applyScheduledMoveIfTime();
+        mScheduledMoveTaskId = taskId;
+        mScheduledMoveTime = SystemClock.uptimeMillis();
+    }
+
+
+    public synchronized ArrayList<Task> reorder(ArrayList<Task> tasks) {
         if (!ENABLE_TASK_STABILIZER.get()) {
             return tasks;
         }
 
-        // Create task id array
-        int count = tasks.size();
-        mTempArray.clear();
-        mTempSet.clear();
-        mTempMap.clear();
+        applyScheduledMoveIfTime();
 
-        for (int i = 0; i < count; i++) {
-            Task t = tasks.get(i);
-            mTempMap.put(t.key.id, t);
-
-            mTempSet.add(t.key.id);
-            mTempArray.add(t.key.id);
+        // Ensure that we have enough wrappers
+        int taskCount = tasks.size();
+        for (int i = taskCount - mTaskWrappers.size(); i > 0; i--) {
+            mTaskWrappers.add(new TaskWrapper());
         }
 
-        if (mLastSet.equals(mTempSet) && isStabilizationQuickEnough()) {
-            if (mLastStableOrder.equals(mTempArray)) {
-                // Everything is same
-                return tasks;
-            }
+        List<TaskWrapper> listToSort = mTaskWrappers.size() == taskCount
+                ? mTaskWrappers : mTaskWrappers.subList(0, taskCount);
+        int missingTaskIndex = -taskCount;
 
-            if (!mLastUnstableOrder.equals(mTempArray)) {
-                // Fast reordering, record the current time.
-                mLastUnstableOrder.copyFrom(mTempArray);
-                mLastReorderTime = SystemClock.uptimeMillis();
-            }
+        for (int i = 0; i < taskCount; i++){
+            TaskWrapper wrapper = listToSort.get(i);
+            wrapper.task = tasks.get(i);
+            wrapper.index = mOrderedTaskIds.indexOf(wrapper.task.key.id);
 
-            // Reorder the tasks based on the last stable order.
-            ArrayList<Task> sorted = new ArrayList<>(count);
-            for (int i = 0; i < count; i++) {
-                sorted.add(mTempMap.get(mLastStableOrder.get(i)));
+            // Ensure that missing tasks are put in the front, in the order they appear in the
+            // original list
+            if (wrapper.index < 0) {
+                wrapper.index = missingTaskIndex;
+                missingTaskIndex++;
             }
-            return sorted;
         }
+        Collections.sort(listToSort);
 
-        // Cache the data
-        mLastStableOrder.copyFrom(mTempArray);
-        mLastUnstableOrder.copyFrom(mTempArray);
-        mLastSet.copyFrom(mTempSet);
-
-        mLastReorderTime = SystemClock.uptimeMillis();
-
-        return tasks;
+        ArrayList<Task> result = new ArrayList<>(taskCount);
+        for (int i = 0; i < taskCount; i++) {
+            result.add(listToSort.get(i).task);
+        }
+        return result;
     }
 
-    private boolean isStabilizationQuickEnough() {
-        return (SystemClock.uptimeMillis() - mLastReorderTime) < TASK_CACHE_TIMEOUT_MS;
+    private static class TaskWrapper implements Comparable<TaskWrapper> {
+        Task task;
+        int index;
+
+        @Override
+        public int compareTo(TaskWrapper other) {
+            return Integer.compare(index, other.index);
+        }
     }
 }
diff --git a/res/values/attrs.xml b/res/values/attrs.xml
index 8c4dd1e..53877ff 100644
--- a/res/values/attrs.xml
+++ b/res/values/attrs.xml
@@ -33,9 +33,11 @@
     <attr name="workspaceKeyShadowColor" format="color" />
     <attr name="workspaceStatusBarScrim" format="reference" />
     <attr name="widgetsTheme" format="reference" />
-    <attr name="folderDotColor" format="color" />
     <attr name="loadingIconColor" format="color" />
 
+    <attr name="folderDotColor" format="color" />
+    <attr name="folderIconRadius" format="float" />
+
     <!-- BubbleTextView specific attributes. -->
     <declare-styleable name="BubbleTextView">
         <attr name="layoutHorizontal" format="boolean" />
diff --git a/res/xml/folder_shapes.xml b/res/xml/folder_shapes.xml
new file mode 100644
index 0000000..e60d333
--- /dev/null
+++ b/res/xml/folder_shapes.xml
@@ -0,0 +1,33 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+ Copyright (C) 2019 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.
+-->
+<shapes xmlns:launcher="http://schemas.android.com/apk/res-auto" >
+
+    <Circle launcher:folderIconRadius="1" />
+
+    <!-- Default icon for AOSP -->
+    <RoundedSquare launcher:folderIconRadius="0.16" />
+
+    <!-- Rounded icon from RRO -->
+    <RoundedSquare launcher:folderIconRadius="0.6" />
+
+    <!-- Square icon -->
+    <RoundedSquare launcher:folderIconRadius="0" />
+
+    <TearDrop launcher:folderIconRadius="0.3" />
+    <Squircle launcher:folderIconRadius="0.2" />
+
+</shapes>
\ No newline at end of file
diff --git a/src/com/android/launcher3/MainProcessInitializer.java b/src/com/android/launcher3/MainProcessInitializer.java
index 9692d73..93df025 100644
--- a/src/com/android/launcher3/MainProcessInitializer.java
+++ b/src/com/android/launcher3/MainProcessInitializer.java
@@ -38,6 +38,6 @@
         FileLog.setDir(context.getApplicationContext().getFilesDir());
         FeatureFlags.initialize(context);
         SessionCommitReceiver.applyDefaultUserPrefs(context);
-        FolderShape.init();
+        FolderShape.init(context);
     }
 }
diff --git a/src/com/android/launcher3/folder/FolderShape.java b/src/com/android/launcher3/folder/FolderShape.java
index ae279cb..f7cdb77 100644
--- a/src/com/android/launcher3/folder/FolderShape.java
+++ b/src/com/android/launcher3/folder/FolderShape.java
@@ -23,6 +23,9 @@
 import android.animation.ValueAnimator;
 import android.animation.ValueAnimator.AnimatorUpdateListener;
 import android.annotation.TargetApi;
+import android.content.Context;
+import android.content.res.TypedArray;
+import android.content.res.XmlResourceParser;
 import android.graphics.Canvas;
 import android.graphics.Color;
 import android.graphics.Paint;
@@ -34,13 +37,28 @@
 import android.graphics.drawable.AdaptiveIconDrawable;
 import android.graphics.drawable.ColorDrawable;
 import android.os.Build;
+import android.util.AttributeSet;
+import android.util.SparseArray;
+import android.util.TypedValue;
+import android.util.Xml;
 import android.view.ViewOutlineProvider;
 
 import com.android.launcher3.Launcher;
 import com.android.launcher3.LauncherAppState;
 import com.android.launcher3.MainThreadExecutor;
+import com.android.launcher3.R;
 import com.android.launcher3.Utilities;
 import com.android.launcher3.anim.RoundedRectRevealOutlineProvider;
+import com.android.launcher3.util.Themes;
+
+import org.xmlpull.v1.XmlPullParser;
+import org.xmlpull.v1.XmlPullParserException;
+
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
+
+import androidx.annotation.Nullable;
 
 /**
  * Abstract representation of the shape of a folder icon
@@ -53,15 +71,7 @@
         return sInstance;
     }
 
-    private static FolderShape[] getAllShapes() {
-        return new FolderShape[] {
-                new Circle(),
-                new RoundedSquare(8f / 50),  // Ratios based on path defined in config_icon_mask
-                new RoundedSquare(30f / 50),
-                new Square(),
-                new TearDrop(),
-                new Squircle()};
-    }
+    private SparseArray<TypedValue> mAttrs;
 
     public abstract void drawShape(Canvas canvas, float offsetX, float offsetY, float radius,
             Paint paint);
@@ -71,6 +81,11 @@
     public abstract Animator createRevealAnimator(Folder target, Rect startRect, Rect endRect,
             float endRadius, boolean isReversed);
 
+    @Nullable
+    public TypedValue getAttrValue(int attr) {
+        return mAttrs == null ? null : mAttrs.get(attr);
+    }
+
     /**
      * Abstract shape where the reveal animation is a derivative of a round rect animation
      */
@@ -163,44 +178,22 @@
         }
     }
 
-    public static class Square extends SimpleRectShape {
-
-        @Override
-        public void drawShape(Canvas canvas, float offsetX, float offsetY, float radius,  Paint p) {
-            float cx = radius + offsetX;
-            float cy = radius + offsetY;
-            canvas.drawRect(cx - radius, cy - radius, cx + radius, cy + radius, p);
-        }
-
-        @Override
-        public void addShape(Path path, float offsetX, float offsetY, float radius) {
-            float cx = radius + offsetX;
-            float cy = radius + offsetY;
-            path.addRect(cx - radius, cy - radius, cx + radius, cy + radius, Path.Direction.CW);
-        }
-
-        @Override
-        protected float getStartRadius(Rect startRect) {
-            return 0;
-        }
-    }
-
     public static class RoundedSquare extends SimpleRectShape {
 
         /**
-         * Ratio of corner radius to half size. Based on the
+         * Ratio of corner radius to half size.
          */
-        private final float mRadiusFactor;
+        private final float mRadiusRatio;
 
-        public RoundedSquare(float radiusFactor) {
-            mRadiusFactor = radiusFactor;
+        public RoundedSquare(float radiusRatio) {
+            mRadiusRatio = radiusRatio;
         }
 
         @Override
         public void drawShape(Canvas canvas, float offsetX, float offsetY, float radius, Paint p) {
             float cx = radius + offsetX;
             float cy = radius + offsetY;
-            float cr = radius * mRadiusFactor;
+            float cr = radius * mRadiusRatio;
             canvas.drawRoundRect(cx - radius, cy - radius, cx + radius, cy + radius, cr, cr, p);
         }
 
@@ -208,14 +201,14 @@
         public void addShape(Path path, float offsetX, float offsetY, float radius) {
             float cx = radius + offsetX;
             float cy = radius + offsetY;
-            float cr = radius * mRadiusFactor;
+            float cr = radius * mRadiusRatio;
             path.addRoundRect(cx - radius, cy - radius, cx + radius, cy + radius, cr, cr,
                     Path.Direction.CW);
         }
 
         @Override
         protected float getStartRadius(Rect startRect) {
-            return (startRect.width() / 2f) * mRadiusFactor;
+            return (startRect.width() / 2f) * mRadiusRatio;
         }
     }
 
@@ -224,13 +217,16 @@
         /**
          * Radio of short radius to large radius, based on the shape options defined in the config.
          */
-        private static final float RADIUS_RATIO = 15f / 50;
-
+        private final float mRadiusRatio;
         private final float[] mTempRadii = new float[8];
 
+        public TearDrop(float radiusRatio) {
+            mRadiusRatio = radiusRatio;
+        }
+
         @Override
         public void addShape(Path p, float offsetX, float offsetY, float r1) {
-            float r2 = r1 * RADIUS_RATIO;
+            float r2 = r1 * mRadiusRatio;
             float cx = r1 + offsetX;
             float cy = r1 + offsetY;
 
@@ -249,7 +245,7 @@
         protected AnimatorUpdateListener newUpdateListener(Rect startRect, Rect endRect,
                 float endRadius, Path outPath) {
             float r1 = startRect.width() / 2f;
-            float r2 = r1 * RADIUS_RATIO;
+            float r2 = r1 * mRadiusRatio;
 
             float[] startValues = new float[] {
                     startRect.left, startRect.top, startRect.right, startRect.bottom, r1, r2};
@@ -273,13 +269,17 @@
         /**
          * Radio of radius to circle radius, based on the shape options defined in the config.
          */
-        private static final float RADIUS_RATIO = 10f / 50;
+        private final float mRadiusRatio;
+
+        public Squircle(float radiusRatio) {
+            mRadiusRatio = radiusRatio;
+        }
 
         @Override
         public void addShape(Path p, float offsetX, float offsetY, float r) {
             float cx = r + offsetX;
             float cy = r + offsetY;
-            float control = r - r * RADIUS_RATIO;
+            float control = r - r * mRadiusRatio;
 
             p.moveTo(cx, cy - r);
             addLeftCurve(cx, cy, r, control, p);
@@ -310,7 +310,7 @@
             float startCX = startRect.exactCenterX();
             float startCY = startRect.exactCenterY();
             float startR = startRect.width() / 2f;
-            float startControl = startR - startR * RADIUS_RATIO;
+            float startControl = startR - startR * mRadiusRatio;
             float startHShift = 0;
             float startVShift = 0;
 
@@ -351,17 +351,63 @@
     }
 
     /**
-     * Initializes the shape which is closest to closest to the {@link AdaptiveIconDrawable}
+     * Initializes the shape which is closest to the {@link AdaptiveIconDrawable}
      */
-    public static void init() {
+    public static void init(Context context) {
         if (!Utilities.ATLEAST_OREO) {
             return;
         }
-        new MainThreadExecutor().execute(FolderShape::pickShapeInBackground);
+        new MainThreadExecutor().execute(() -> pickShapeInBackground(context));
+    }
+
+    private static FolderShape getShapeDefinition(String type, float radius) {
+        switch (type) {
+            case "Circle":
+                return new Circle();
+            case "RoundedSquare":
+                return new RoundedSquare(radius);
+            case "TearDrop":
+                return new TearDrop(radius);
+            case "Squircle":
+                return new Squircle(radius);
+            default:
+                throw new IllegalArgumentException("Invalid shape type: " + type);
+        }
+    }
+
+    private static List<FolderShape> getAllShapes(Context context) {
+        ArrayList<FolderShape> result = new ArrayList<>();
+        try (XmlResourceParser parser = context.getResources().getXml(R.xml.folder_shapes)) {
+
+            // Find the root tag
+            int type;
+            while ((type = parser.next()) != XmlPullParser.END_TAG
+                    && type != XmlPullParser.END_DOCUMENT
+                    && !"shapes".equals(parser.getName()));
+
+            final int depth = parser.getDepth();
+            int[] radiusAttr = new int[] {R.attr.folderIconRadius};
+            while (((type = parser.next()) != XmlPullParser.END_TAG ||
+                    parser.getDepth() > depth) && type != XmlPullParser.END_DOCUMENT) {
+
+                if (type == XmlPullParser.START_TAG) {
+                    AttributeSet attrs = Xml.asAttributeSet(parser);
+                    TypedArray a = context.obtainStyledAttributes(attrs, radiusAttr);
+                    FolderShape shape = getShapeDefinition(parser.getName(), a.getFloat(0, 1));
+                    a.recycle();
+
+                    shape.mAttrs = Themes.createValueMap(context, attrs);
+                    result.add(shape);
+                }
+            }
+        } catch (IOException | XmlPullParserException e) {
+            throw new RuntimeException(e);
+        }
+        return result;
     }
 
     @TargetApi(Build.VERSION_CODES.O)
-    protected static void pickShapeInBackground() {
+    protected static void pickShapeInBackground(Context context) {
         // Pick any large size
         int size = 200;
 
@@ -379,7 +425,7 @@
         // Find the shape with minimum area of divergent region.
         int minArea = Integer.MAX_VALUE;
         FolderShape closestShape = null;
-        for (FolderShape shape : getAllShapes()) {
+        for (FolderShape shape : getAllShapes(context)) {
             shapePath.reset();
             shape.addShape(shapePath, 0, 0, size / 2f);
             shapeR.setPath(shapePath, full);
diff --git a/src/com/android/launcher3/model/AddWorkspaceItemsTask.java b/src/com/android/launcher3/model/AddWorkspaceItemsTask.java
index 5fc5551..0d55301 100644
--- a/src/com/android/launcher3/model/AddWorkspaceItemsTask.java
+++ b/src/com/android/launcher3/model/AddWorkspaceItemsTask.java
@@ -62,7 +62,7 @@
         final IntArray addedWorkspaceScreensFinal = new IntArray();
 
         synchronized(dataModel) {
-            IntArray workspaceScreens = dataModel.workspaceScreens.clone();
+            IntArray workspaceScreens = dataModel.collectWorkspaceScreens();
 
             List<ItemInfo> filteredItems = new ArrayList<>();
             for (Pair<ItemInfo, Object> entry : mItemList) {
diff --git a/src/com/android/launcher3/model/BaseLoaderResults.java b/src/com/android/launcher3/model/BaseLoaderResults.java
index f6e220f..23c6faf 100644
--- a/src/com/android/launcher3/model/BaseLoaderResults.java
+++ b/src/com/android/launcher3/model/BaseLoaderResults.java
@@ -92,7 +92,7 @@
         synchronized (mBgDataModel) {
             workspaceItems.addAll(mBgDataModel.workspaceItems);
             appWidgets.addAll(mBgDataModel.appWidgets);
-            orderedScreenIds.addAll(mBgDataModel.workspaceScreens);
+            orderedScreenIds.addAll(mBgDataModel.collectWorkspaceScreens());
             mBgDataModel.lastBindId++;
         }
 
diff --git a/src/com/android/launcher3/model/BgDataModel.java b/src/com/android/launcher3/model/BgDataModel.java
index 151d6f4..b338fff 100644
--- a/src/com/android/launcher3/model/BgDataModel.java
+++ b/src/com/android/launcher3/model/BgDataModel.java
@@ -27,6 +27,7 @@
 import com.android.launcher3.LauncherAppWidgetInfo;
 import com.android.launcher3.LauncherSettings;
 import com.android.launcher3.ShortcutInfo;
+import com.android.launcher3.Workspace;
 import com.android.launcher3.config.FeatureFlags;
 import com.android.launcher3.logging.DumpTargetWrapper;
 import com.android.launcher3.model.nano.LauncherDumpProto;
@@ -37,6 +38,7 @@
 import com.android.launcher3.shortcuts.ShortcutKey;
 import com.android.launcher3.util.ComponentKey;
 import com.android.launcher3.util.IntArray;
+import com.android.launcher3.util.IntSet;
 import com.android.launcher3.util.IntSparseArrayMap;
 import com.google.protobuf.nano.MessageNano;
 
@@ -81,11 +83,6 @@
     public final IntSparseArrayMap<FolderInfo> folders = new IntSparseArrayMap<>();
 
     /**
-     * Ordered list of workspace screens ids.
-     */
-    public final IntArray workspaceScreens = new IntArray();
-
-    /**
      * Map of ShortcutKey to the number of times it is pinned.
      */
     public final Map<ShortcutKey, MutableInt> pinnedShortcutCounts = new HashMap<>();
@@ -118,11 +115,26 @@
         appWidgets.clear();
         folders.clear();
         itemsIdMap.clear();
-        workspaceScreens.clear();
         pinnedShortcutCounts.clear();
         deepShortcutMap.clear();
     }
 
+    /**
+     * Creates an array of valid workspace screens based on current items in the model.
+     */
+    public synchronized IntArray collectWorkspaceScreens() {
+        IntSet screenSet = new IntSet();
+        for (ItemInfo item: itemsIdMap) {
+            if (item.container == LauncherSettings.Favorites.CONTAINER_DESKTOP) {
+                screenSet.add(item.screenId);
+            }
+        }
+        if (FeatureFlags.QSB_ON_FIRST_SCREEN.get() || screenSet.isEmpty()) {
+            screenSet.add(Workspace.FIRST_SCREEN_ID);
+        }
+        return screenSet.getArray();
+    }
+
     public synchronized void dump(String prefix, FileDescriptor fd, PrintWriter writer,
             String[] args) {
         if (Arrays.asList(args).contains("--proto")) {
@@ -130,11 +142,6 @@
             return;
         }
         writer.println(prefix + "Data Model:");
-        writer.print(prefix + " ---- workspace screens: ");
-        for (int i = 0; i < workspaceScreens.size(); i++) {
-            writer.print(" " + workspaceScreens.get(i));
-        }
-        writer.println();
         writer.println(prefix + " ---- workspace items ");
         for (int i = 0; i < workspaceItems.size(); i++) {
             writer.println(prefix + '\t' + workspaceItems.get(i).toString());
@@ -167,6 +174,7 @@
         // Add top parent nodes. (L1)
         DumpTargetWrapper hotseat = new DumpTargetWrapper(ContainerType.HOTSEAT, 0);
         IntSparseArrayMap<DumpTargetWrapper> workspaces = new IntSparseArrayMap<>();
+        IntArray workspaceScreens = collectWorkspaceScreens();
         for (int i = 0; i < workspaceScreens.size(); i++) {
             workspaces.put(workspaceScreens.get(i),
                     new DumpTargetWrapper(ContainerType.WORKSPACE, i));
diff --git a/src/com/android/launcher3/model/LoaderTask.java b/src/com/android/launcher3/model/LoaderTask.java
index 8a6aa1af..cfabc10 100644
--- a/src/com/android/launcher3/model/LoaderTask.java
+++ b/src/com/android/launcher3/model/LoaderTask.java
@@ -31,7 +31,6 @@
 import android.content.pm.LauncherActivityInfo;
 import android.content.pm.PackageInstaller;
 import android.content.pm.PackageInstaller.SessionInfo;
-import android.graphics.Bitmap;
 import android.os.Handler;
 import android.os.Process;
 import android.os.UserHandle;
@@ -43,19 +42,17 @@
 import com.android.launcher3.AllAppsList;
 import com.android.launcher3.AppInfo;
 import com.android.launcher3.FolderInfo;
-import com.android.launcher3.ItemInfoWithIcon;
-import com.android.launcher3.icons.ComponentWithLabel;
-import com.android.launcher3.icons.ComponentWithLabel.ComponentCachingLogic;
-import com.android.launcher3.icons.cache.IconCacheUpdateHandler;
-import com.android.launcher3.icons.IconCache;
 import com.android.launcher3.InstallShortcutReceiver;
 import com.android.launcher3.ItemInfo;
+import com.android.launcher3.ItemInfoWithIcon;
 import com.android.launcher3.LauncherAppState;
 import com.android.launcher3.LauncherAppWidgetInfo;
 import com.android.launcher3.LauncherModel;
 import com.android.launcher3.LauncherSettings;
+import com.android.launcher3.LauncherSettings.Favorites;
 import com.android.launcher3.ShortcutInfo;
 import com.android.launcher3.Utilities;
+import com.android.launcher3.Workspace;
 import com.android.launcher3.compat.AppWidgetManagerCompat;
 import com.android.launcher3.compat.LauncherAppsCompat;
 import com.android.launcher3.compat.PackageInstallerCompat;
@@ -63,16 +60,18 @@
 import com.android.launcher3.config.FeatureFlags;
 import com.android.launcher3.folder.Folder;
 import com.android.launcher3.folder.FolderIconPreviewVerifier;
+import com.android.launcher3.icons.ComponentWithLabel;
+import com.android.launcher3.icons.ComponentWithLabel.ComponentCachingLogic;
+import com.android.launcher3.icons.IconCache;
 import com.android.launcher3.icons.LauncherActivtiyCachingLogic;
 import com.android.launcher3.icons.LauncherIcons;
+import com.android.launcher3.icons.cache.IconCacheUpdateHandler;
 import com.android.launcher3.logging.FileLog;
 import com.android.launcher3.provider.ImportDataTask;
 import com.android.launcher3.shortcuts.DeepShortcutManager;
 import com.android.launcher3.shortcuts.ShortcutInfoCompat;
 import com.android.launcher3.shortcuts.ShortcutKey;
 import com.android.launcher3.util.ComponentKey;
-import com.android.launcher3.util.IntArray;
-import com.android.launcher3.util.IntSet;
 import com.android.launcher3.util.LooperIdleLock;
 import com.android.launcher3.util.MultiHashMap;
 import com.android.launcher3.util.PackageManagerHelper;
@@ -158,9 +157,9 @@
             allItems.addAll(mBgDataModel.workspaceItems);
             allItems.addAll(mBgDataModel.appWidgets);
         }
-        int firstScreen = mBgDataModel.workspaceScreens.isEmpty()
-                ? -1 // In this case, we can still look at the items in the hotseat.
-                : mBgDataModel.workspaceScreens.get(0);
+        // Screen set is never empty
+        final int firstScreen = mBgDataModel.collectWorkspaceScreens().get(0);
+
         filterCurrentWorkspaceItems(firstScreen, allItems, firstScreenItems,
                 new ArrayList<>() /* otherScreenItems are ignored */);
         mFirstScreenBroadcast.sendBroadcasts(mApp.getContext(), firstScreenItems);
@@ -784,16 +783,6 @@
                         null,
                         new Handler(LauncherModel.getWorkerLooper()));
             }
-
-            // Initialize the screens array. Using an InstSet ensures that the screen ids
-            // are sorted.
-            IntSet screenSet = new IntSet();
-            for (ItemInfo item: mBgDataModel.itemsIdMap) {
-                if (item.container == LauncherSettings.Favorites.CONTAINER_DESKTOP) {
-                    screenSet.add(item.screenId);
-                }
-            }
-            mBgDataModel.workspaceScreens.addAll(screenSet.getArray());
         }
     }
 
diff --git a/src/com/android/launcher3/util/Themes.java b/src/com/android/launcher3/util/Themes.java
index 5f965a3..e3ab1a5 100644
--- a/src/com/android/launcher3/util/Themes.java
+++ b/src/com/android/launcher3/util/Themes.java
@@ -21,6 +21,9 @@
 import android.graphics.Color;
 import android.graphics.ColorMatrix;
 import android.graphics.drawable.Drawable;
+import android.util.AttributeSet;
+import android.util.SparseArray;
+import android.util.TypedValue;
 
 /**
  * Various utility methods associated with theming.
@@ -104,4 +107,26 @@
         target.getArray()[14] = Color.blue(dstColor) - Color.blue(srcColor);
         target.getArray()[19] = Color.alpha(dstColor) - Color.alpha(srcColor);
     }
+
+    /**
+     * Creates a map for attribute-name to value for all the values in {@param attrs} which can be
+     * held in memory for later use.
+     */
+    public static SparseArray<TypedValue> createValueMap(Context context, AttributeSet attrSet) {
+        int count = attrSet.getAttributeCount();
+        int[] attrNames = new int[count];
+        for (int i = 0; i < count; i++) {
+            attrNames[i] = attrSet.getAttributeNameResource(i);
+        }
+
+        SparseArray<TypedValue> result = new SparseArray<>(count);
+        TypedArray ta = context.obtainStyledAttributes(attrSet, attrNames);
+        for (int i = 0; i < count; i++) {
+            TypedValue tv = new TypedValue();
+            ta.getValue(i, tv);
+            result.put(attrNames[i], tv);
+        }
+
+        return result;
+    }
 }