Dev preview changes for incompatible apps.

- Disable drop targets when picking up a task that can’t be docked, and
  show toast notifying user (for now)
- When a task is docked, update the task headers for non-dockable tasks
  to indicate that they don’t support multi window.  Update these 
  headers every time the multi window state changes.

Bug: 26774190
Change-Id: I020dcbac9b1230dba166eecaa12366986e684f9e
diff --git a/packages/SystemUI/src/com/android/systemui/recents/RecentsActivity.java b/packages/SystemUI/src/com/android/systemui/recents/RecentsActivity.java
index c2a6108..c41098f 100644
--- a/packages/SystemUI/src/com/android/systemui/recents/RecentsActivity.java
+++ b/packages/SystemUI/src/com/android/systemui/recents/RecentsActivity.java
@@ -528,17 +528,16 @@
     @Override
     public void onMultiWindowChanged(boolean inMultiWindow) {
         super.onMultiWindowChanged(inMultiWindow);
-        if (!inMultiWindow) {
-            RecentsTaskLoader loader = Recents.getTaskLoader();
-            RecentsTaskLoadPlan.Options launchOpts = new RecentsTaskLoadPlan.Options();
-            launchOpts.loadIcons = false;
-            launchOpts.loadThumbnails = false;
-            launchOpts.onlyLoadForCache = true;
-            RecentsTaskLoadPlan loadPlan = loader.createLoadPlan(this);
-            loader.preloadTasks(loadPlan, -1, false);
-            loader.loadTasks(this, loadPlan, launchOpts);
-            EventBus.getDefault().send(new TaskStackUpdatedEvent(loadPlan.getTaskStack()));
-        }
+        RecentsTaskLoader loader = Recents.getTaskLoader();
+        RecentsTaskLoadPlan.Options launchOpts = new RecentsTaskLoadPlan.Options();
+        launchOpts.loadIcons = false;
+        launchOpts.loadThumbnails = false;
+        launchOpts.onlyLoadForCache = true;
+        RecentsTaskLoadPlan loadPlan = loader.createLoadPlan(this);
+        loader.preloadTasks(loadPlan, -1, false);
+        loader.loadTasks(this, loadPlan, launchOpts);
+        EventBus.getDefault().send(new TaskStackUpdatedEvent(loadPlan.getTaskStack(),
+                inMultiWindow));
     }
 
     @Override
diff --git a/packages/SystemUI/src/com/android/systemui/recents/events/activity/TaskStackUpdatedEvent.java b/packages/SystemUI/src/com/android/systemui/recents/events/activity/TaskStackUpdatedEvent.java
index f87f6de..0d614e8c 100644
--- a/packages/SystemUI/src/com/android/systemui/recents/events/activity/TaskStackUpdatedEvent.java
+++ b/packages/SystemUI/src/com/android/systemui/recents/events/activity/TaskStackUpdatedEvent.java
@@ -28,8 +28,10 @@
      * A new TaskStack instance representing the latest stack state.
      */
     public final TaskStack stack;
+    public final boolean inMultiWindow;
 
-    public TaskStackUpdatedEvent(TaskStack stack) {
+    public TaskStackUpdatedEvent(TaskStack stack, boolean inMultiWindow) {
         this.stack = stack;
+        this.inMultiWindow = inMultiWindow;
     }
 }
diff --git a/packages/SystemUI/src/com/android/systemui/recents/model/RecentsTaskLoadPlan.java b/packages/SystemUI/src/com/android/systemui/recents/model/RecentsTaskLoadPlan.java
index 824231a..6fef8a2 100644
--- a/packages/SystemUI/src/com/android/systemui/recents/model/RecentsTaskLoadPlan.java
+++ b/packages/SystemUI/src/com/android/systemui/recents/model/RecentsTaskLoadPlan.java
@@ -198,8 +198,8 @@
             // Add the task to the stack
             Task task = new Task(taskKey, t.affiliatedTaskId, t.affiliatedTaskColor, icon,
                     thumbnail, title, contentDescription, dismissDescription, activityColor,
-                    backgroundColor, !isStackTask, isLaunchTarget, isSystemApp, t.bounds,
-                    t.taskDescription);
+                    backgroundColor, !isStackTask, isLaunchTarget, isSystemApp, t.isDockable,
+                    t.bounds, t.taskDescription);
 
             allTasks.add(task);
             affiliatedTaskCounts.put(taskKey.id, affiliatedTaskCounts.get(taskKey.id, 0) + 1);
diff --git a/packages/SystemUI/src/com/android/systemui/recents/model/Task.java b/packages/SystemUI/src/com/android/systemui/recents/model/Task.java
index 8ed6dd7..e5d4f1b 100644
--- a/packages/SystemUI/src/com/android/systemui/recents/model/Task.java
+++ b/packages/SystemUI/src/com/android/systemui/recents/model/Task.java
@@ -168,6 +168,8 @@
     public boolean isHistorical;
     @ViewDebug.ExportedProperty(category="recents")
     public boolean isSystemApp;
+    @ViewDebug.ExportedProperty(category="recents")
+    public boolean isDockable;
 
     private ArrayList<TaskCallbacks> mCallbacks = new ArrayList<>();
 
@@ -178,8 +180,8 @@
     public Task(TaskKey key, int affiliationTaskId, int affiliationColor, Drawable icon,
                 Bitmap thumbnail, String title, String contentDescription,
                 String dismissDescription, int colorPrimary, int colorBackground,
-                boolean isHistorical, boolean isLaunchTarget, boolean isSystemApp, Rect bounds,
-                ActivityManager.TaskDescription taskDescription) {
+                boolean isHistorical, boolean isLaunchTarget, boolean isSystemApp,
+                boolean isDockable, Rect bounds, ActivityManager.TaskDescription taskDescription) {
         boolean isInAffiliationGroup = (affiliationTaskId != key.id);
         boolean hasAffiliationGroupColor = isInAffiliationGroup && (affiliationColor != 0);
         this.key = key;
@@ -199,6 +201,7 @@
         this.isLaunchTarget = isLaunchTarget;
         this.isHistorical = isHistorical;
         this.isSystemApp = isSystemApp;
+        this.isDockable = isDockable;
     }
 
     /** Copies the other task. */
@@ -219,6 +222,7 @@
         this.isLaunchTarget = o.isLaunchTarget;
         this.isHistorical = o.isHistorical;
         this.isSystemApp = o.isSystemApp;
+        this.isDockable = o.isDockable;
     }
 
     /**
diff --git a/packages/SystemUI/src/com/android/systemui/recents/views/RecentsView.java b/packages/SystemUI/src/com/android/systemui/recents/views/RecentsView.java
index 2e45627..5dde926 100644
--- a/packages/SystemUI/src/com/android/systemui/recents/views/RecentsView.java
+++ b/packages/SystemUI/src/com/android/systemui/recents/views/RecentsView.java
@@ -663,8 +663,10 @@
     }
 
     public final void onBusEvent(TaskStackUpdatedEvent event) {
-        mStack.setTasks(event.stack.computeAllTasksList(), true /* notifyStackChanges */);
-        mStack.createAffiliatedGroupings(getContext());
+        if (!event.inMultiWindow) {
+            mStack.setTasks(event.stack.computeAllTasksList(), true /* notifyStackChanges */);
+            mStack.createAffiliatedGroupings(getContext());
+        }
     }
 
     public final void onBusEvent(EnterRecentsWindowAnimationCompletedEvent event) {
diff --git a/packages/SystemUI/src/com/android/systemui/recents/views/RecentsViewTouchHandler.java b/packages/SystemUI/src/com/android/systemui/recents/views/RecentsViewTouchHandler.java
index 016d937..079d7b9 100644
--- a/packages/SystemUI/src/com/android/systemui/recents/views/RecentsViewTouchHandler.java
+++ b/packages/SystemUI/src/com/android/systemui/recents/views/RecentsViewTouchHandler.java
@@ -21,7 +21,9 @@
 import android.view.MotionEvent;
 import android.view.ViewConfiguration;
 import android.view.ViewDebug;
+import android.widget.Toast;
 
+import com.android.systemui.R;
 import com.android.systemui.recents.Recents;
 import com.android.systemui.recents.RecentsConfiguration;
 import com.android.systemui.recents.events.EventBus;
@@ -148,11 +150,16 @@
 
         mVisibleDockStates.clear();
         if (!ssp.hasDockedTask() && mRv.getTaskStack().getTaskCount() > 1) {
-            // Add the dock state drop targets (these take priority)
-            TaskStack.DockState[] dockStates = getDockStatesForCurrentOrientation();
-            for (TaskStack.DockState dockState : dockStates) {
-                registerDropTargetForCurrentDrag(dockState);
-                mVisibleDockStates.add(dockState);
+            if (!event.task.isDockable) {
+                Toast.makeText(mRv.getContext(), R.string.recents_drag_non_dockable_task_message,
+                        Toast.LENGTH_SHORT).show();
+            } else {
+                // Add the dock state drop targets (these take priority)
+                TaskStack.DockState[] dockStates = getDockStatesForCurrentOrientation();
+                for (TaskStack.DockState dockState : dockStates) {
+                    registerDropTargetForCurrentDrag(dockState);
+                    mVisibleDockStates.add(dockState);
+                }
             }
         }
 
diff --git a/packages/SystemUI/src/com/android/systemui/recents/views/TaskStackView.java b/packages/SystemUI/src/com/android/systemui/recents/views/TaskStackView.java
index d71d70f..afa5188 100644
--- a/packages/SystemUI/src/com/android/systemui/recents/views/TaskStackView.java
+++ b/packages/SystemUI/src/com/android/systemui/recents/views/TaskStackView.java
@@ -1830,12 +1830,28 @@
     }
 
     public final void onBusEvent(TaskStackUpdatedEvent event) {
-        // Scroll the stack to the front after it has been updated
+        if (!event.inMultiWindow) {
+            // Scroll the stack to the front after it has been updated
+            event.addPostAnimationCallback(new Runnable() {
+                @Override
+                public void run() {
+                    mStackScroller.animateScroll(mLayoutAlgorithm.mMaxScrollP,
+                            null /* postScrollRunnable */);
+                }
+            });
+        }
+        // When the multi-window state changes, rebind all task view headers again to update their
+        // dockable state
         event.addPostAnimationCallback(new Runnable() {
             @Override
             public void run() {
-                mStackScroller.animateScroll(mLayoutAlgorithm.mMaxScrollP,
-                        null /* postScrollRunnable */);
+                List<TaskView> taskViews = getTaskViews();
+                int taskViewCount = taskViews.size();
+                for (int i = 0; i < taskViewCount; i++) {
+                    TaskView tv = taskViews.get(i);
+                    tv.getHeaderView().rebindToTask(tv.getTask(), tv.mTouchExplorationEnabled,
+                            tv.mIsDisabledInSafeMode);
+                }
             }
         });
     }
diff --git a/packages/SystemUI/src/com/android/systemui/recents/views/TaskViewHeader.java b/packages/SystemUI/src/com/android/systemui/recents/views/TaskViewHeader.java
index 0543dd5..05a8527 100644
--- a/packages/SystemUI/src/com/android/systemui/recents/views/TaskViewHeader.java
+++ b/packages/SystemUI/src/com/android/systemui/recents/views/TaskViewHeader.java
@@ -139,6 +139,7 @@
     // Header views
     ImageView mIconView;
     TextView mTitleView;
+    TextView mSubTitleView;
     ImageView mMoveTaskButton;
     ImageView mDismissButton;
     ViewStub mAppOverlayViewStub;
@@ -237,6 +238,7 @@
         mIconView.setClickable(false);
         mIconView.setOnLongClickListener(this);
         mTitleView = (TextView) findViewById(R.id.title);
+        mSubTitleView = (TextView) findViewById(R.id.sub_title);
         mDismissButton = (ImageView) findViewById(R.id.dismiss_task);
         if (ssp.hasFreeformWorkspaceSupport()) {
             mMoveTaskButton = (ImageView) findViewById(R.id.move_task);
@@ -367,6 +369,7 @@
 
     /** Binds the bar view to the task */
     public void rebindToTask(Task t, boolean touchExplorationEnabled, boolean disabledInSafeMode) {
+        SystemServicesProxy ssp = Recents.getSystemServices();
         mTask = t;
 
         // If an activity icon is defined, then we use that as the primary icon to show in the bar,
@@ -384,6 +387,13 @@
         mTitleView.setContentDescription(t.contentDescription);
         mTitleView.setTextColor(t.useLightOnPrimaryColor ?
                 mTaskBarViewLightTextColor : mTaskBarViewDarkTextColor);
+        if (!t.isDockable && ssp.hasDockedTask()) {
+            mSubTitleView.setVisibility(View.VISIBLE);
+            mSubTitleView.setTextColor(t.useLightOnPrimaryColor ?
+                    mTaskBarViewLightTextColor : mTaskBarViewDarkTextColor);
+        } else {
+            mSubTitleView.setVisibility(View.GONE);
+        }
         mDismissButton.setImageDrawable(t.useLightOnPrimaryColor ?
                 mLightDismissDrawable : mDarkDismissDrawable);
         mDismissButton.setContentDescription(t.dismissDescription);