Add distance threshold for dragged items before accepted by targets.

With the new spring-loaded workspace, items are often very close to
button drop targets (e.g. App Info) at the start of a drag. This
threshold makes it less likely to accidentally drop on a target.

Bug: 24099531
Change-Id: I4912ceeb0b63958816177c7bde073e825176d987

1 files changed, 7 insertions, 0 deletions

diff --git a/src/com/android/launcher3/dragndrop/DragController.java b/src/com/android/launcher3/dragndrop/DragController.java
index 7524128d4..f4470f320 100644
--- a/src/com/android/launcher3/dragndrop/DragController.java
+++ b/src/com/android/launcher3/dragndrop/DragController.java
@@ -276,6 +276,9 @@ public class DragController implements DragDriver.EventListener {
 
         mLauncher.getDragLayer().performHapticFeedback(HapticFeedbackConstants.LONG_PRESS);
         dragView.show(mMotionDownX, mMotionDownY);
+        mDistanceSinceScroll = 0;
+        mLastTouch[0] = mMotionDownX;
+        mLastTouch[1] = mMotionDownY;
         handleMoveEvent(mMotionDownX, mMotionDownY);
         return dragView;
     }
@@ -536,6 +539,10 @@ public class DragController implements DragDriver.EventListener {
         checkScrollState(x, y);
     }
 
+    public float getDistanceDragged() {
+        return mDistanceSinceScroll;
+    }
+
     public void forceTouchMove() {
         int[] dummyCoordinates = mCoordinatesTemp;
         DropTarget dropTarget = findDropTarget(mLastTouch[0], mLastTouch[1], dummyCoordinates);