Bug 1525796 - Ignore close tab action if user is moving the item; r=JanH

Using an ItemTouchHelper for various motion actions means it will have a
strong reference to that item's layout and prevent it from being destroyed when
the adapter tries to remove it before the animations are finished - the item
will be removed from RecyclerView's Adapter but the item's layout will still
remain on screen.

Differential Revision: https://phabricator.services.mozilla.com/D19673

--HG--
extra : moz-landing-system : lando

mobile/android/base/java/org/mozilla/gecko/tabs/TabsGridLayout.java

@@ -26,13 +26,13 @@ abstract class TabsGridLayout extends TabsLayout {
 
         final int dragDirections = ItemTouchHelper.UP | ItemTouchHelper.DOWN | ItemTouchHelper.START | ItemTouchHelper.END;
         // A TouchHelper handler for drag and drop and swipe to close.
-        final TabsTouchHelperCallback callback = new TabsTouchHelperCallback(this, dragDirections, this) {
+        tabTouchCallback = new TabsTouchHelperCallback(this, dragDirections, this) {
             @Override
             protected float alphaForItemSwipeDx(float dX, int distanceToAlphaMin) {
                 return 1f - 2f * Math.abs(dX) / distanceToAlphaMin;
             }
         };
-        final ItemTouchHelper touchHelper = new ItemTouchHelper(callback);
+        final ItemTouchHelper touchHelper = new ItemTouchHelper(tabTouchCallback);
         touchHelper.attachToRecyclerView(this);
     }
 

mobile/android/base/java/org/mozilla/gecko/tabs/TabsLayout.java

@@ -33,6 +33,7 @@ public abstract class TabsLayout extends RecyclerView
     private TabsPanel tabsPanel;
     private final TabsLayoutAdapter tabsAdapter;
     private View emptyView;
+    protected TabsTouchHelperCallback tabTouchCallback;
 
     public TabsLayout(Context context, AttributeSet attrs, int itemViewLayoutResId) {
         super(context, attrs);
@@ -46,10 +47,14 @@ public abstract class TabsLayout extends RecyclerView
                 new Button.OnClickListener() {
                     @Override
                     public void onClick(View v) {
-                        // The view here is the close button, which has a reference
-                        // to the parent TabsLayoutItemView in its tag, hence the getTag() call.
-                        TabsLayoutItemView itemView = (TabsLayoutItemView) v.getTag();
-                        closeTab(itemView);
+                        // Bug 1525796: ignore action if the user already interacts with the whole view
+                        // with the help of an ItemTouchHelper
+                        if (tabTouchCallback == null || !tabTouchCallback.isInteractionInProgress()) {
+                            // The view here is the close button, which has a reference
+                            // to the parent TabsLayoutItemView in its tag, hence the getTag() call.
+                            TabsLayoutItemView itemView = (TabsLayoutItemView) v.getTag();
+                            closeTab(itemView);
+                        }
                     }
                 });
         setAdapter(tabsAdapter);

mobile/android/base/java/org/mozilla/gecko/tabs/TabsListLayout.java

@@ -34,14 +34,14 @@ public class TabsListLayout extends TabsLayout {
 
         final int dragDirections = ItemTouchHelper.UP | ItemTouchHelper.DOWN;
         // A TouchHelper handler for drag and drop and swipe to close.
-        final TabsTouchHelperCallback callback = new TabsTouchHelperCallback(this, dragDirections, this) {
+        tabTouchCallback = new TabsTouchHelperCallback(this, dragDirections, this) {
             @Override
             protected float alphaForItemSwipeDx(float dX, int distanceToAlphaMin) {
                 return Math.max(0.1f,
                         Math.min(1f, 1f - 2f * Math.abs(dX) / distanceToAlphaMin));
             }
         };
-        final ItemTouchHelper touchHelper = new ItemTouchHelper(callback);
+        final ItemTouchHelper touchHelper = new ItemTouchHelper(tabTouchCallback);
         touchHelper.attachToRecyclerView(this);
 
         setItemAnimator(new TabsListLayoutAnimator(ANIMATION_DURATION));

mobile/android/base/java/org/mozilla/gecko/tabs/TabsTouchHelperCallback.java

@@ -16,6 +16,7 @@ class TabsTouchHelperCallback extends ItemTouchHelper.Callback {
     private final @Nullable DismissListener dismissListener;
     private final @NonNull DragListener dragListener;
     private final int movementFlags;
+    private boolean isInteractionInProgress;
 
     interface DismissListener {
         void onItemDismiss(View view);
@@ -96,6 +97,25 @@ class TabsTouchHelperCallback extends ItemTouchHelper.Callback {
     @Override
     public void clearView(RecyclerView recyclerView, RecyclerView.ViewHolder viewHolder) {
         super.clearView(recyclerView, viewHolder);
+
         viewHolder.itemView.setAlpha(1);
+
+        isInteractionInProgress = false;
+    }
+
+    @Override
+    public void onSelectedChanged(RecyclerView.ViewHolder viewHolder, int actionState) {
+        super.onSelectedChanged(viewHolder, actionState);
+
+        if (viewHolder != null) {
+            isInteractionInProgress = true;
+        }
+    }
+
+    /**
+     * Get if user started interacting with RecyclerView's items and their animations have not yet completed.
+     */
+    public boolean isInteractionInProgress() {
+        return isInteractionInProgress;
     }
 }