[android] - avoid triggering a fling gesture after a scale gesture. (#7675)

platform/android/CHANGELOG.md

@@ -33,6 +33,8 @@ Mapbox welcomes participation and contributions from everyone.  If you'd like to
   - Rename to reflect the increased responsibilities introduced in prior releases
 * AnnotationManager refactor [#6067](https://github.com/mapbox/mapbox-gl-native/issues/6067)
   - Extracting all business logic related to annotations into a seperate class cfr. to core and the iOS codebase
+* Gesture handling bugs
+  - Avoid calls to onFling when while pinch zooming [#7666](https://github.com/mapbox/mapbox-gl-native/issues/7666)
 
 ## 4.2.1 - December 22, 2016
 

platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/maps/MapGestureDetector.java

@@ -49,6 +49,7 @@ final class MapGestureDetector {
   private boolean dragStarted = false;
   private boolean quickZoom = false;
   private boolean scrollInProgress = false;
+  private boolean scaleGestureOccurred = false;
 
   MapGestureDetector(Context context, Transform transform, Projection projection, UiSettings uiSettings,
                      TrackingSettings trackingSettings, AnnotationManager annotationManager) {
@@ -111,7 +112,8 @@ final class MapGestureDetector {
     // Handle two finger tap
     switch (event.getActionMasked()) {
       case MotionEvent.ACTION_DOWN:
-        // First pointer down
+        // First pointer down, reset scaleGestureOccurred, used to avoid triggering a fling after a scale gesture #7666
+        scaleGestureOccurred = false;
         transform.setGestureInProgress(true);
         break;
 
@@ -294,7 +296,9 @@ final class MapGestureDetector {
 
     @Override
     public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
-      if (!trackingSettings.isScrollGestureCurrentlyEnabled()) {
+      if ((!trackingSettings.isScrollGestureCurrentlyEnabled()) || scaleGestureOccurred) {
+        // don't allow a fling is scroll is disabled
+        // and ignore when a scale gesture has occurred
         return false;
       }
 
@@ -368,6 +372,7 @@ final class MapGestureDetector {
         return false;
       }
 
+      scaleGestureOccurred = true;
       beginTime = detector.getEventTime();
       MapboxEvent.trackGestureEvent(projection,
         MapboxEvent.GESTURE_PINCH_START, detector.getFocusX(), detector.getFocusY(), transform.getZoom());