Use GestureDetector in WorkspaceTouchListener

Replace the current callback logic in WorkspaceTouchListener with the
use of GestureDetector.
Platform-provided api will now be used  for detecting long press.

Test: long press on empty home screen
Bug: 126596502
Change-Id: I5beb9158ee0d9ec6ac031465f15923eed2d5f066

src/com/android/launcher3/touch/WorkspaceTouchListener.java

@@ -20,12 +20,12 @@ import static android.view.MotionEvent.ACTION_DOWN;
 import static android.view.MotionEvent.ACTION_MOVE;
 import static android.view.MotionEvent.ACTION_POINTER_UP;
 import static android.view.MotionEvent.ACTION_UP;
-import static android.view.ViewConfiguration.getLongPressTimeout;
 
 import static com.android.launcher3.LauncherState.NORMAL;
 
 import android.graphics.PointF;
 import android.graphics.Rect;
+import android.view.GestureDetector;
 import android.view.HapticFeedbackConstants;
 import android.view.MotionEvent;
 import android.view.View;
@@ -45,7 +45,8 @@ import com.android.launcher3.userevent.nano.LauncherLogProto.ContainerType;
 /**
  * Helper class to handle touch on empty space in workspace and show options popup on long press
  */
-public class WorkspaceTouchListener implements OnTouchListener, Runnable {
+public class WorkspaceTouchListener extends GestureDetector.SimpleOnGestureListener
+        implements OnTouchListener {
 
     /**
      * STATE_PENDING_PARENT_INFORM is the state between longPress performed & the next motionEvent.
@@ -66,16 +67,21 @@ public class WorkspaceTouchListener implements OnTouchListener, Runnable {
 
     private int mLongPressState = STATE_CANCELLED;
 
+    private final GestureDetector mGestureDetector;
+
     public WorkspaceTouchListener(Launcher launcher, Workspace workspace) {
         mLauncher = launcher;
         mWorkspace = workspace;
         // Use twice the touch slop as we are looking for long press which is more
         // likely to cause movement.
         mTouchSlop = 2 * ViewConfiguration.get(launcher).getScaledTouchSlop();
+        mGestureDetector = new GestureDetector(workspace.getContext(), this);
     }
 
     @Override
     public boolean onTouch(View view, MotionEvent ev) {
+        mGestureDetector.onTouchEvent(ev);
+
         int action = ev.getActionMasked();
         if (action == ACTION_DOWN) {
             // Check if we can handle long press.
@@ -97,7 +103,6 @@ public class WorkspaceTouchListener implements OnTouchListener, Runnable {
             if (handleLongPress) {
                 mLongPressState = STATE_REQUESTED;
                 mTouchDownPoint.set(ev.getX(), ev.getY());
-                mWorkspace.postDelayed(this, getLongPressTimeout());
             }
 
             mWorkspace.onTouchEvent(ev);
@@ -143,9 +148,6 @@ public class WorkspaceTouchListener implements OnTouchListener, Runnable {
             }
         }
 
-        if (action == ACTION_UP || action == ACTION_CANCEL) {
-            cancelLongPress();
-        }
         return result;
     }
 
@@ -155,12 +157,11 @@ public class WorkspaceTouchListener implements OnTouchListener, Runnable {
     }
 
     private void cancelLongPress() {
-        mWorkspace.removeCallbacks(this);
         mLongPressState = STATE_CANCELLED;
     }
 
     @Override
-    public void run() {
+    public void onLongPress(MotionEvent event) {
         if (mLongPressState == STATE_REQUESTED) {
             if (canHandleLongPress()) {
                 mLongPressState = STATE_PENDING_PARENT_INFORM;