Merge "Disabling fast scroller when searching apps." into ub-launcher3-burnaby-polish

src/com/android/launcher3/BaseRecyclerView.java

@@ -267,6 +267,13 @@ public abstract class BaseRecyclerView extends RecyclerView
         mScrollbar.setThumbOffset(scrollBarX, scrollBarY);
     }
 
+    /**
+     * Returns whether fast scrolling is supported in the current state.
+     */
+    protected boolean supportsFastScrolling() {
+        return true;
+    }
+
     /**
      * Maps the touch (from 0..1) to the adapter position that should be visible.
      * <p>Override in each subclass of this base class.

src/com/android/launcher3/BaseRecyclerViewFastScrollBar.java

@@ -189,7 +189,8 @@ public class BaseRecyclerViewFastScrollBar {
                 // Check if we should start scrolling, but ignore this fastscroll gesture if we have
                 // exceeded some fixed movement
                 mIgnoreDragGesture |= Math.abs(y - downY) > config.getScaledPagingTouchSlop();
-                if (!mIsDragging && !mIgnoreDragGesture && isNearThumb(downX, lastY) &&
+                if (!mIsDragging && !mIgnoreDragGesture && mRv.supportsFastScrolling() &&
+                        isNearThumb(downX, lastY) &&
                         Math.abs(y - downY) > config.getScaledTouchSlop()) {
                     mRv.getParent().requestDisallowInterceptTouchEvent(true);
                     mIsDragging = true;

src/com/android/launcher3/allapps/AllAppsRecyclerView.java

@@ -431,6 +431,13 @@ public class AllAppsRecyclerView extends BaseRecyclerView
         }
     }
 
+    @Override
+    protected boolean supportsFastScrolling() {
+        // Only allow fast scrolling when the user is not searching, since the results are not
+        // grouped in a meaningful order
+        return !mApps.hasFilter();
+    }
+
     /**
      * Returns the scrollY for the given position in the adapter.
      */