From 6f50ca34c45d79847765d9802f39466ea7b0d62e Mon Sep 17 00:00:00 2001
From: Ats Jenk <atsjenk@google.com>
Date: Mon, 30 Jan 2023 17:32:30 -0800
Subject: [PATCH] Pin desktop tile to the right in overview

When desktop windowing prototype is enabled, pin desktop tile to the
right of the focused tile.
Also making desktop tile persistent so it will always show up,
regardless whether there are tasks added to the desktop or not.
Fixing some nullpointer issues that stem from that.

Bug: 261234155
Test: no recent tasks, go to overview, shows empty view
Test: only desktop tasks, go to overview from home, desktop tile focused
Test: only desktop tasks, desktop open, go to overview, desktop tile
  focused
Test: 1 fullscreen task and some desktop tasks, go to overview from home
  screen, fullscreen tile focused
Test: fullscreen task open and no desktop tasks, go to overview,
  fullscreen task focused and empty desktop tile on the right
Test: fullscreen task open and some desktop tasks in background, go to
  overview, fullscreen tile focused, desktop tile on the right
Test: some desktop tasks focused, some fullscreen tasks in background,
  go to overview, desktop tile focused, fullscreen tasks on the left

Change-Id: Ib28185b40f639d36b82b6d0e3c61026ec84e245c
---
 quickstep/res/layout/task_desktop.xml         |  3 +-
 .../quickstep/views/DesktopTaskView.java      | 18 ++---
 .../android/quickstep/views/RecentsView.java  | 65 ++++++++++++++++---
 .../com/android/quickstep/views/TaskView.java |  7 +-
 4 files changed, 74 insertions(+), 19 deletions(-)

diff --git a/quickstep/res/layout/task_desktop.xml b/quickstep/res/layout/task_desktop.xml
index 0c8543f414..2a9674f90b 100644
--- a/quickstep/res/layout/task_desktop.xml
+++ b/quickstep/res/layout/task_desktop.xml
@@ -33,7 +33,8 @@
     <com.android.quickstep.views.TaskThumbnailView
         android:id="@+id/snapshot"
         android:layout_width="wrap_content"
-        android:layout_height="wrap_content" />
+        android:layout_height="wrap_content"
+        android:visibility="gone" />
 
     <com.android.quickstep.views.IconView
         android:id="@+id/icon"
diff --git a/quickstep/src/com/android/quickstep/views/DesktopTaskView.java b/quickstep/src/com/android/quickstep/views/DesktopTaskView.java
index 44aa41a655..709ce71cb2 100644
--- a/quickstep/src/com/android/quickstep/views/DesktopTaskView.java
+++ b/quickstep/src/com/android/quickstep/views/DesktopTaskView.java
@@ -74,7 +74,8 @@ public class DesktopTaskView extends TaskView {
 
     private static final boolean DEBUG = true;
 
-    private List<Task> mTasks;
+    @NonNull
+    private List<Task> mTasks = new ArrayList<>();
 
     private final ArrayList<TaskThumbnailView> mSnapshotViews = new ArrayList<>();
 
@@ -108,8 +109,6 @@ public class DesktopTaskView extends TaskView {
                 getContext().getTheme()));
         // TODO(b/244348395): this should be wallpaper
         setBackground(mBackground);
-
-        mSnapshotViews.add(mSnapshotView);
     }
 
     @Override
@@ -129,12 +128,9 @@ public class DesktopTaskView extends TaskView {
             }
             Log.d(TAG, sb.toString());
         }
-        if (tasks.isEmpty()) {
-            return;
-        }
         cancelPendingLoadTasks();
 
-        mTasks = tasks;
+        mTasks = new ArrayList<>(tasks);
         mSnapshotViewMap.clear();
 
         // Ensure there are equal number of snapshot views and tasks.
@@ -207,7 +203,8 @@ public class DesktopTaskView extends TaskView {
         if (task != null) {
             return mSnapshotViewMap.get(task.key.id);
         }
-        return null;
+        // Return the place holder snapshot views. Callers expect this to be non-null
+        return mSnapshotView;
     }
 
     @Override
@@ -313,6 +310,11 @@ public class DesktopTaskView extends TaskView {
         callback.accept(true);
     }
 
+    @Override
+    public boolean isDesktopTask() {
+        return true;
+    }
+
     @Override
     void refreshThumbnails(@Nullable HashMap<Integer, ThumbnailData> thumbnailDatas) {
         // Sets new thumbnails based on the incoming data and refreshes the rest.
diff --git a/quickstep/src/com/android/quickstep/views/RecentsView.java b/quickstep/src/com/android/quickstep/views/RecentsView.java
index 8facb0a35e..d8ecd872fb 100644
--- a/quickstep/src/com/android/quickstep/views/RecentsView.java
+++ b/quickstep/src/com/android/quickstep/views/RecentsView.java
@@ -1548,8 +1548,14 @@ public abstract class RecentsView<ACTIVITY_TYPE extends StatefulActivity<STATE_T
         removeView(focusedTaskView);
         mMovingTaskView = null;
         focusedTaskView.resetPersistentViewTransforms();
-        addView(focusedTaskView, 0);
-        setCurrentPage(0);
+        int frontTaskIndex = 0;
+        if (DesktopTaskView.DESKTOP_IS_PROTO2_ENABLED && !focusedTaskView.isDesktopTask()) {
+            // If desktop mode is enabled, desktop task view is pinned at first position.
+            // Move focused task to position 1
+            frontTaskIndex = 1;
+        }
+        addView(focusedTaskView, frontTaskIndex);
+        setCurrentPage(frontTaskIndex);
 
         updateGridProperties();
     }
@@ -1586,7 +1592,7 @@ public abstract class RecentsView<ACTIVITY_TYPE extends StatefulActivity<STATE_T
 
         int currentTaskId = -1;
         TaskView currentTaskView = getTaskViewAt(mCurrentPage);
-        if (currentTaskView != null) {
+        if (currentTaskView != null && currentTaskView.getTask() != null) {
             currentTaskId = currentTaskView.getTask().key.id;
         }
 
@@ -1615,6 +1621,8 @@ public abstract class RecentsView<ACTIVITY_TYPE extends StatefulActivity<STATE_T
         // update the map of instance counts
         mFilterState.updateInstanceCountMap(taskGroups);
 
+        DesktopTask desktopTask = null;
+
         // Add views as children based on whether it's grouped or single task. Looping through
         // taskGroups backwards populates the thumbnail grid from least recent to most recent.
         for (int i = taskGroups.size() - 1; i >= 0; i--) {
@@ -1622,6 +1630,12 @@ public abstract class RecentsView<ACTIVITY_TYPE extends StatefulActivity<STATE_T
             boolean isRemovalNeeded = stagedTaskIdToBeRemovedFromGrid != INVALID_TASK_ID
                     && groupTask.containsTask(stagedTaskIdToBeRemovedFromGrid);
 
+            if (groupTask instanceof DesktopTask) {
+                desktopTask = (DesktopTask) groupTask;
+                // Desktop task will be added separately in the end
+                continue;
+            }
+
             TaskView taskView;
             if (isRemovalNeeded && groupTask.hasMultipleTasks()) {
                 // If we need to remove half of a pair of tasks, force a TaskView with Type.SINGLE
@@ -1652,9 +1666,6 @@ public abstract class RecentsView<ACTIVITY_TYPE extends StatefulActivity<STATE_T
 
                 ((GroupedTaskView) taskView).bind(leftTopTask, rightBottomTask, mOrientationState,
                         groupTask.mSplitBounds);
-            } else if (taskView instanceof DesktopTaskView) {
-                ((DesktopTaskView) taskView).bind(((DesktopTask) groupTask).tasks,
-                        mOrientationState);
             } else {
                 taskView.bind(groupTask.task1, mOrientationState);
             }
@@ -1667,6 +1678,14 @@ public abstract class RecentsView<ACTIVITY_TYPE extends StatefulActivity<STATE_T
 
         if (!taskGroups.isEmpty()) {
             addView(mClearAllButton);
+
+            if (DesktopTaskView.DESKTOP_IS_PROTO2_ENABLED) {
+                TaskView taskView = getTaskViewFromPool(TaskView.Type.DESKTOP);
+                // Always add a desktop task to the first position. Even if it is empty
+                addView(taskView, 0);
+                ArrayList<Task> tasks = desktopTask != null ? desktopTask.tasks : new ArrayList<>();
+                ((DesktopTaskView) taskView).bind(tasks, mOrientationState);
+            }
         }
 
         // Keep same previous focused task
@@ -1674,6 +1693,12 @@ public abstract class RecentsView<ACTIVITY_TYPE extends StatefulActivity<STATE_T
         // If the list changed, maybe the focused task doesn't exist anymore
         if (newFocusedTaskView == null && getTaskViewCount() > 0) {
             newFocusedTaskView = getTaskViewAt(0);
+            // Check if the first task is the desktop.
+            // If first task is desktop, try to find another task to set as the focused task
+            if (newFocusedTaskView != null && newFocusedTaskView.isDesktopTask()
+                    && getTaskViewCount() > 1) {
+                newFocusedTaskView = getTaskViewAt(1);
+            }
         }
         mFocusedTaskViewId = newFocusedTaskView != null ?
                 newFocusedTaskView.getTaskViewId() : -1;
@@ -1707,7 +1732,12 @@ public abstract class RecentsView<ACTIVITY_TYPE extends StatefulActivity<STATE_T
             if (runningTaskId != -1) {
                 targetPage = indexOfChild(newRunningTaskView);
             } else if (getTaskViewCount() > 0) {
-                targetPage = indexOfChild(requireTaskViewAt(0));
+                TaskView taskView = requireTaskViewAt(0);
+                // If first task id desktop, try to find another task to set the target page
+                if (taskView.isDesktopTask() && getTaskViewCount() > 1) {
+                    taskView = requireTaskViewAt(1);
+                }
+                targetPage = indexOfChild(taskView);
             }
         }
         if (targetPage != -1 && mCurrentPage != targetPage) {
@@ -2136,6 +2166,9 @@ public abstract class RecentsView<ACTIVITY_TYPE extends StatefulActivity<STATE_T
         for (int i = 0; i < getTaskViewCount(); i++) {
             TaskView taskView = requireTaskViewAt(i);
             Task task = taskView.getTask();
+            if (task == null) {
+                continue;
+            }
             int index = indexOfChild(taskView);
             boolean visible;
             if (showAsGrid()) {
@@ -2710,6 +2743,8 @@ public abstract class RecentsView<ACTIVITY_TYPE extends StatefulActivity<STATE_T
         TaskView homeTaskView = getHomeTaskView();
         TaskView nextFocusedTaskView = null;
 
+        int desktopTaskIndex = Integer.MAX_VALUE;
+
         if (!isTaskDismissal) {
             mTopRowIdSet.clear();
         }
@@ -2736,6 +2771,14 @@ public abstract class RecentsView<ACTIVITY_TYPE extends StatefulActivity<STATE_T
                     // If focused task is snapped, the row width is just task width and spacing.
                     snappedTaskRowWidth = taskWidthAndSpacing;
                 }
+            } else if (taskView.isDesktopTask()) {
+                // Desktop task was not focused. Pin it to the right of focused
+                desktopTaskIndex = i;
+                gridTranslations[i] += mIsRtl ? taskWidthAndSpacing : -taskWidthAndSpacing;
+
+                // Center view vertically in case it's from different orientation.
+                taskView.setGridTranslationY((mLastComputedTaskSize.height() + taskTopMargin
+                        - taskView.getLayoutParams().height) / 2f);
             } else {
                 if (i > focusedTaskIndex) {
                     // For tasks after the focused task, shift by focused task's width and spacing.
@@ -2776,7 +2819,7 @@ public abstract class RecentsView<ACTIVITY_TYPE extends StatefulActivity<STATE_T
                     // Move horizontally into empty space.
                     float widthOffset = 0;
                     for (int j = i - 1; !topSet.contains(j) && j >= 0; j--) {
-                        if (j == focusedTaskIndex) {
+                        if (j == focusedTaskIndex || j == desktopTaskIndex) {
                             continue;
                         }
                         widthOffset += requireTaskViewAt(j).getLayoutParams().width + mPageSpacing;
@@ -2795,7 +2838,7 @@ public abstract class RecentsView<ACTIVITY_TYPE extends StatefulActivity<STATE_T
                     // Move horizontally into empty space.
                     float widthOffset = 0;
                     for (int j = i - 1; !bottomSet.contains(j) && j >= 0; j--) {
-                        if (j == focusedTaskIndex) {
+                        if (j == focusedTaskIndex || j == desktopTaskIndex) {
                             continue;
                         }
                         widthOffset += requireTaskViewAt(j).getLayoutParams().width + mPageSpacing;
@@ -5096,6 +5139,10 @@ public abstract class RecentsView<ACTIVITY_TYPE extends StatefulActivity<STATE_T
     }
 
     private int getFirstViewIndex() {
+        if (DesktopTaskView.DESKTOP_IS_PROTO2_ENABLED) {
+            // Desktop task is at position 0, that is the first view
+            return 0;
+        }
         TaskView focusedTaskView = mShowAsGridLastOnLayout ? getFocusedTaskView() : null;
         return focusedTaskView != null ? indexOfChild(focusedTaskView) : 0;
     }
diff --git a/quickstep/src/com/android/quickstep/views/TaskView.java b/quickstep/src/com/android/quickstep/views/TaskView.java
index aa37fddb8b..473691d053 100644
--- a/quickstep/src/com/android/quickstep/views/TaskView.java
+++ b/quickstep/src/com/android/quickstep/views/TaskView.java
@@ -1007,6 +1007,11 @@ public class TaskView extends FrameLayout implements Reusable {
         return deviceProfile.isTablet && !isFocusedTask();
     }
 
+    /** Whether this task view represents the desktop */
+    public boolean isDesktopTask() {
+        return false;
+    }
+
     /**
      * Called to animate a smooth transition when going directly from an app into Overview (and
      * vice versa). Icons fade in, and DWB banners slide in with a "shift up" animation.
@@ -1517,7 +1522,7 @@ public class TaskView extends FrameLayout implements Reusable {
             int boxWidth;
             int boxHeight;
             boolean isFocusedTask = isFocusedTask();
-            if (isFocusedTask) {
+            if (isFocusedTask || isDesktopTask()) {
                 // Task will be focused and should use focused task size. Use focusTaskRatio
                 // that is associated with the original orientation of the focused task.
                 boxWidth = taskWidth;