Implement Shutter callback. Add GestureAction.TAKE_PICTURE_SNAPSHOT. (#1030)

* include swipe and shutter callback

* Swipe Left and Right callback on CameraListener.
* Shutter event callback on CameraListener.

* Add Gesture Action TakePictureSnapshot

Added a new GestureAction.TAKE_PICTURE_SNAPSHOT that calls takePictureSnapshot() method.

* take_picture_snapshot GestureAction

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

@@ -161,4 +161,12 @@ public abstract class CameraListener {
 
     }
 
-}
+    /**
+     * Notifies that the shutter event is happening. You can update UI to show some
+     * trigger effect, so user visually confirms that picture is being taken
+     * or video recording is about to start.
+     */
+    @UiThread
+    public void onShutter() {}
+    
+}

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

@@ -669,6 +669,10 @@ public class CameraView extends FrameLayout implements LifecycleObserver {
         //noinspection ConstantConditions
         switch (action) {
 
+            case TAKE_PICTURE_SNAPSHOT:
+                takePictureSnapshot();
+                break;
+
             case TAKE_PICTURE:
                 takePicture();
                 break;
@@ -2228,6 +2232,14 @@ public class CameraView extends FrameLayout implements LifecycleObserver {
             if (shouldPlaySound && mPlaySounds) {
                 playSound(MediaActionSound.SHUTTER_CLICK);
             }
+            mUiHandler.post(new Runnable() {
+                @Override
+                public void run() {
+                    for (CameraListener listener : mListeners) {
+                        listener.onShutter();
+                    }
+                }
+            });
         }
 
         @Override

cameraview/src/main/java/com/otaliastudios/cameraview/gesture/GestureAction.java

@@ -43,6 +43,15 @@ public enum GestureAction {
      */
     TAKE_PICTURE(2, GestureType.ONE_SHOT),
 
+    /**
+     * When triggered, this action will fire a picture snapshot.
+     * This action can be mapped to one shot gestures:
+     *
+     * - {@link Gesture#TAP}
+     * - {@link Gesture#LONG_TAP}
+     */
+    TAKE_PICTURE_SNAPSHOT(3, GestureType.ONE_SHOT),
+
     /**
      * Zoom control, typically assigned to the pinch gesture.
      * This action can be mapped to continuous gestures:
@@ -51,7 +60,7 @@ public enum GestureAction {
      * - {@link Gesture#SCROLL_HORIZONTAL}
      * - {@link Gesture#SCROLL_VERTICAL}
      */
-    ZOOM(3, GestureType.CONTINUOUS),
+    ZOOM(4, GestureType.CONTINUOUS),
 
     /**
      * Exposure correction control.
@@ -61,7 +70,7 @@ public enum GestureAction {
      * - {@link Gesture#SCROLL_HORIZONTAL}
      * - {@link Gesture#SCROLL_VERTICAL}
      */
-    EXPOSURE_CORRECTION(4, GestureType.CONTINUOUS),
+    EXPOSURE_CORRECTION(5, GestureType.CONTINUOUS),
 
     /**
      * Controls the first parameter of a real-time {@link Filter},
@@ -71,7 +80,7 @@ public enum GestureAction {
      * - {@link Gesture#SCROLL_HORIZONTAL}
      * - {@link Gesture#SCROLL_VERTICAL}
      */
-    FILTER_CONTROL_1(5, GestureType.CONTINUOUS),
+    FILTER_CONTROL_1(6, GestureType.CONTINUOUS),
 
     /**
      * Controls the second parameter of a real-time {@link Filter},
@@ -81,7 +90,7 @@ public enum GestureAction {
      * - {@link Gesture#SCROLL_HORIZONTAL}
      * - {@link Gesture#SCROLL_VERTICAL}
      */
-    FILTER_CONTROL_2(6, GestureType.CONTINUOUS);
+    FILTER_CONTROL_2(7, GestureType.CONTINUOUS);
 
     final static GestureAction DEFAULT_PINCH = NONE;
     final static GestureAction DEFAULT_TAP = NONE;

cameraview/src/main/res/values/attrs.xml

@@ -40,36 +40,38 @@
             <enum name="none" value="0" />
             <enum name="autoFocus" value="1" />
             <enum name="takePicture" value="2" />
+            <enum name="takePictureSnapshot" value="3" />
         </attr>
 
         <attr name="cameraGestureLongTap" format="enum">
             <enum name="none" value="0" />
             <enum name="autoFocus" value="1" />
             <enum name="takePicture" value="2" />
+            <enum name="takePictureSnapshot" value="3" />
         </attr>
 
         <attr name="cameraGesturePinch" format="enum">
             <enum name="none" value="0" />
-            <enum name="zoom" value="3" />
-            <enum name="exposureCorrection" value="4" />
-            <enum name="filterControl1" value="5" />
-            <enum name="filterControl2" value="6" />
+            <enum name="zoom" value="4" />
+            <enum name="exposureCorrection" value="5" />
+            <enum name="filterControl1" value="6" />
+            <enum name="filterControl2" value="7" />
         </attr>
 
         <attr name="cameraGestureScrollHorizontal" format="enum">
             <enum name="none" value="0" />
-            <enum name="zoom" value="3" />
-            <enum name="exposureCorrection" value="4" />
-            <enum name="filterControl1" value="5" />
-            <enum name="filterControl2" value="6" />
+            <enum name="zoom" value="4" />
+            <enum name="exposureCorrection" value="5" />
+            <enum name="filterControl1" value="6" />
+            <enum name="filterControl2" value="7" />
         </attr>
 
         <attr name="cameraGestureScrollVertical" format="enum">
             <enum name="none" value="0" />
-            <enum name="zoom" value="3" />
-            <enum name="exposureCorrection" value="4" />
-            <enum name="filterControl1" value="5" />
-            <enum name="filterControl2" value="6" />
+            <enum name="zoom" value="4" />
+            <enum name="exposureCorrection" value="5" />
+            <enum name="filterControl1" value="6" />
+            <enum name="filterControl2" value="7" />
         </attr>
 
         <attr name="cameraEngine" format="enum">