1 files changed, 20 insertions, 11 deletions
diff --git a/androidx/recyclerview/selection/SelectionTracker.java b/androidx/recyclerview/selection/SelectionTracker.java
index 2b35f5d7..283426f6 100644
--- a/androidx/recyclerview/selection/SelectionTracker.java
+++ b/androidx/recyclerview/selection/SelectionTracker.java
@@ -29,6 +29,8 @@ import androidx.annotation.DrawableRes;
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.recyclerview.widget.RecyclerView;
+import androidx.recyclerview.widget.RecyclerView.AdapterDataObserver;
+import androidx.recyclerview.widget.RecyclerView.OnItemTouchListener;
 
 import java.util.Set;
 
@@ -119,7 +121,7 @@ public abstract class SelectionTracker<K> {
      * of the selection that will not reflect future changes
      * to selection.
      */
-    public abstract Selection getSelection();
+    public abstract Selection<K> getSelection();
 
     /**
      * Updates {@code dest} to reflect the current selection.
@@ -175,7 +177,7 @@ public abstract class SelectionTracker<K> {
      */
     public abstract boolean deselect(@NonNull K key);
 
-    abstract void onDataSetChanged();
+    abstract AdapterDataObserver getAdapterDataObserver();
 
     /**
      * Attempts to establish a range selection at {@code position}, selecting the item
@@ -471,7 +473,7 @@ public abstract class SelectionTracker<K> {
                 MotionEvent.TOOL_TYPE_UNKNOWN
         };
 
-        private int[] mBandToolTypes = new int[] {
+        private int[] mPointerToolTypes = new int[] {
                 MotionEvent.TOOL_TYPE_MOUSE
         };
 
@@ -637,14 +639,16 @@ public abstract class SelectionTracker<K> {
         }
 
         /**
-         * Replaces default band selection tool-types. Defaults are:
+         * Replaces default pointer tool-types. Pointer tools
+         * are associated with band selection, and certain
+         * drag and drop behaviors. Defaults are:
          * {@link MotionEvent#TOOL_TYPE_MOUSE}.
          *
          * @param toolTypes the tool types to be used
          * @return this
          */
-        public Builder<K> withBandTooltypes(int... toolTypes) {
-            mBandToolTypes = toolTypes;
+        public Builder<K> withPointerTooltypes(int... toolTypes) {
+            mPointerToolTypes = toolTypes;
             return this;
         }
 
@@ -769,10 +773,12 @@ public abstract class SelectionTracker<K> {
                     mOnItemActivatedListener,
                     mFocusDelegate);
 
-            for (int toolType : mBandToolTypes) {
+            for (int toolType : mPointerToolTypes) {
                 gestureRouter.register(toolType, mouseHandler);
             }
 
+            @Nullable BandSelectionHelper bandHelper = null;
+
             // Band selection not supported in single select mode, or when key access
             // is limited to anything less than the entire corpus.
             if (mKeyProvider.hasAccess(ItemKeyProvider.SCOPE_MAPPED)
@@ -782,7 +788,7 @@ public abstract class SelectionTracker<K> {
                 // necessarily models and caches list/grid information as the user's pointer
                 // interacts with the item in the RecyclerView. Selectable items that intersect
                 // with the band, both on and off screen, are selected.
-                BandSelectionHelper bandHelper = BandSelectionHelper.create(
+                bandHelper = BandSelectionHelper.create(
                         mRecyclerView,
                         scroller,
                         mBandOverlayId,
@@ -792,10 +798,13 @@ public abstract class SelectionTracker<K> {
                         mBandPredicate,
                         mFocusDelegate,
                         mMonitor);
+            }
+
+            OnItemTouchListener pointerEventHandler = new PointerDragEventInterceptor(
+                    mDetailsLookup, mOnDragInitiatedListener, bandHelper);
 
-                for (int toolType : mBandToolTypes) {
-                    eventRouter.register(toolType, bandHelper);
-                }
+            for (int toolType : mPointerToolTypes) {
+                eventRouter.register(toolType, pointerEventHandler);
             }
 
             return tracker;