Add flag to disable automatic gesture handling (#1068)

* Add flag to disable automatic gesture handling

* Toggle onInterceptTouchEvents based on active gestures instead of adding a new flag

* Add test for gesture toggle

cameraview/src/androidTest/java/com/otaliastudios/cameraview/CameraViewTest.java

@@ -216,6 +216,17 @@ public class CameraViewTest extends BaseTest {
         assertEquals(cameraView.getGestureAction(Gesture.PINCH), GestureAction.NONE);
     }
 
+    @Test
+    public void testGesture_enabled() {
+        // Ensure touch events are intercepted when at least one gesture is set
+        cameraView.mapGesture(Gesture.PINCH, GestureAction.ZOOM);
+        assertTrue(cameraView.onInterceptTouchEvent(null));
+
+        // Ensure touch events are NOT intercepted when no gestures are set
+        cameraView.clearGesture(Gesture.PINCH);
+        assertFalse(cameraView.onInterceptTouchEvent(null));
+    }
+
     @Test
     public void testGesture_enablingDisablingLayouts() {
         cameraView.clearGesture(Gesture.TAP);

cameraview/src/main/java/com/otaliastudios/cameraview/CameraView.java

@@ -133,6 +133,7 @@ public class CameraView extends FrameLayout implements LifecycleObserver {
     private Engine mEngine;
     private Filter mPendingFilter;
     private int mFrameProcessingExecutors;
+    private int mActiveGestures;
 
     // Components
     private Handler mUiHandler;
@@ -605,6 +606,12 @@ public class CameraView extends FrameLayout implements LifecycleObserver {
                             mGestureMap.get(Gesture.SCROLL_VERTICAL) != none);
                     break;
             }
+
+            mActiveGestures = 0;
+            for(GestureAction act : mGestureMap.values()) {
+                mActiveGestures += act == GestureAction.NONE ? 0 : 1;
+            }
+
             return true;
         }
         mapGesture(gesture, none);
@@ -633,7 +640,8 @@ public class CameraView extends FrameLayout implements LifecycleObserver {
 
     @Override
     public boolean onInterceptTouchEvent(MotionEvent ev) {
-        return true; // Steal our own events.
+        // Steal our own events if gestures are enabled
+        return mActiveGestures > 0;
     }
 
     @SuppressLint("ClickableViewAccessibility")