Make CameraView thread-safe (#97)

* Make CameraController fully async, fix shutter sounds, tests

* Schedule everything to the same handler

* Ignore integration tests in travis

* Add basic error handling

* Revert useless logs

README.md

@@ -44,6 +44,7 @@ See below for a [list of what was done](#roadmap) and [licensing info](#contribu
   - Automatically detected orientation tags
   - Plug in location tags with `setLocation()` API
 - `CameraUtils` to help with Bitmaps and orientations
+- Error handling
 - **Lightweight**, no dependencies, just support `ExifInterface`
 - Works down to API level 15
 
@@ -169,6 +170,16 @@ camera.addCameraListener(new CameraListener() {
     @Override
     public void onCameraClosed() {}
 
+    /**
+     * Notifies about an error during the camera setup or configuration.
+     * At the moment, errors that are passed here are unrecoverable. When this is called,
+     * the camera has been released and is presumably showing a black preview.
+     *
+     * This is the right moment to show an error dialog to the user.
+     */
+    @Override
+    public void onCameraError(CameraException error) {}
+
     /**
      * Notifies that a picture previously captured with capturePicture()
      * or captureSnapshot() is ready to be shown or saved.
@@ -605,6 +616,7 @@ all the code was changed.
 - *Better threading, start() in worker thread and callbacks in UI*
 - *Frame processor support*
 - *inject external loggers*
+- *error handling*
 
 These are still things that need to be done, off the top of my head:
 
@@ -612,7 +624,6 @@ These are still things that need to be done, off the top of my head:
 - [ ] add a `setPreferredAspectRatio` API to choose the capture size. Preview size will adapt, and then, if let free, the CameraView will adapt as well
 - [ ] animate grid lines similar to stock camera app
 - [ ] add onRequestPermissionResults for easy permission callback
-- [ ] better error handling, maybe with a onError(e) method in the public listener, or have each public method return a boolean
 - [ ] decent code coverage
 
 # Contributing and licenses

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

@@ -48,8 +48,7 @@ public class CameraUtilsTest extends BaseTest {
         source.compress(Bitmap.CompressFormat.PNG, 100, os);
         final byte[] data = os.toByteArray();
 
-        final Task<Bitmap> decode = new Task<>();
-        decode.listen();
+        final Task<Bitmap> decode = new Task<>(true);
         final CameraUtils.BitmapCallback callback = new CameraUtils.BitmapCallback() {
             @Override
             public void onBitmapReady(Bitmap bitmap) {

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

@@ -34,7 +34,7 @@ import static org.mockito.Mockito.verify;
 
 @RunWith(AndroidJUnit4.class)
 @MediumTest
-public class CameraCallbacksTest extends BaseTest {
+public class CameraViewCallbacksTest extends BaseTest {
 
     private CameraView camera;
     private CameraListener listener;
@@ -73,8 +73,7 @@ public class CameraCallbacksTest extends BaseTest {
                 camera.instantiatePreview();
                 camera.addCameraListener(listener);
                 camera.addFrameProcessor(processor);
-                task = new Task<>();
-                task.listen();
+                task = new Task<>(true);
             }
         });
     }
@@ -225,6 +224,17 @@ public class CameraCallbacksTest extends BaseTest {
         verify(listener, times(1)).onOrientationChanged(anyInt());
     }
 
+    // TODO: test onShutter, here or elsewhere
+
+    @Test
+    public void testCameraError() {
+        CameraException error = new CameraException(new RuntimeException("Error"));
+        completeTask().when(listener).onCameraError(error);
+
+        camera.mCameraCallbacks.dispatchError(error);
+        assertNotNull(task.await(200));
+        verify(listener, times(1)).onCameraError(error);
+    }
 
     @Test
     public void testProcessJpeg() {
@@ -264,8 +274,7 @@ public class CameraCallbacksTest extends BaseTest {
 
     private int[] testProcessImage(boolean jpeg, boolean crop, int[] viewDim, int[] imageDim) {
         // End our task when onPictureTaken is called. Take note of the result.
-        final Task<byte[]> jpegTask = new Task<>();
-        jpegTask.listen();
+        final Task<byte[]> jpegTask = new Task<>(true);
         doAnswer(new Answer() {
             @Override
             public Object answer(InvocationOnMock invocation) throws Throwable {

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

@@ -92,10 +92,10 @@ public class CameraViewTest extends BaseTest {
         assertEquals(cameraView.getAudio(), Audio.DEFAULT);
         assertEquals(cameraView.getVideoQuality(), VideoQuality.DEFAULT);
         assertEquals(cameraView.getLocation(), null);
-
-        // Self managed
         assertEquals(cameraView.getExposureCorrection(), 0f, 0f);
         assertEquals(cameraView.getZoom(), 0f, 0f);
+
+        // Self managed
         assertEquals(cameraView.getPlaySounds(), CameraView.DEFAULT_PLAY_SOUNDS);
         assertEquals(cameraView.getCropOutput(), CameraView.DEFAULT_CROP_OUTPUT);
         assertEquals(cameraView.getJpegQuality(), CameraView.DEFAULT_JPEG_QUALITY);

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

@@ -1,13 +1,12 @@
 package com.otaliastudios.cameraview;
 
 
-import android.content.Context;
 import android.graphics.Bitmap;
 import android.graphics.PointF;
+import android.media.MediaRecorder;
 import android.support.test.filters.MediumTest;
 import android.support.test.rule.ActivityTestRule;
 import android.support.test.runner.AndroidJUnit4;
-import android.view.ViewGroup;
 
 import org.junit.After;
 import org.junit.Before;
@@ -42,6 +41,7 @@ public class IntegrationTest extends BaseTest {
     private CameraView camera;
     private Camera1 controller;
     private CameraListener listener;
+    private Task<Throwable> uiExceptionTask;
 
     @BeforeClass
     public static void grant() {
@@ -51,6 +51,7 @@ public class IntegrationTest extends BaseTest {
     @Before
     public void setUp() {
         WorkerHandler.destroy();
+
         ui(new Runnable() {
             @Override
             public void run() {
@@ -67,6 +68,17 @@ public class IntegrationTest extends BaseTest {
                 rule.getActivity().inflate(camera);
             }
         });
+
+        // Ensure that controller exceptions are thrown on this thread (not on the UI thread).
+        uiExceptionTask = new Task<>(true);
+        WorkerHandler crashThread = WorkerHandler.get("CrashThread");
+        crashThread.getThread().setUncaughtExceptionHandler(new Thread.UncaughtExceptionHandler() {
+            @Override
+            public void uncaughtException(Thread t, Throwable e) {
+                uiExceptionTask.end(e);
+            }
+        });
+        controller.mCrashHandler = crashThread.get();
     }
 
     @After
@@ -76,9 +88,14 @@ public class IntegrationTest extends BaseTest {
         WorkerHandler.destroy();
     }
 
+    private void waitForUiException() throws Throwable {
+        Throwable throwable = uiExceptionTask.await(2500);
+        if (throwable != null) throw throwable;
+    }
+
     private CameraOptions waitForOpen(boolean expectSuccess) {
-        final Task<CameraOptions> open = new Task<>();
-        open.listen();
+        camera.start();
+        final Task<CameraOptions> open = new Task<>(true);
         doEndTask(open, 0).when(listener).onCameraOpened(any(CameraOptions.class));
         CameraOptions result = open.await(4000);
         if (expectSuccess) {
@@ -89,9 +106,9 @@ public class IntegrationTest extends BaseTest {
         return result;
     }
 
-    private Boolean waitForClose(boolean expectSuccess) {
-        final Task<Boolean> close = new Task<>();
-        close.listen();
+    private void waitForClose(boolean expectSuccess) {
+        camera.stop();
+        final Task<Boolean> close = new Task<>(true);
         doEndTask(close, true).when(listener).onCameraClosed();
         Boolean result = close.await(4000);
         if (expectSuccess) {
@@ -99,25 +116,21 @@ public class IntegrationTest extends BaseTest {
         } else {
             assertNull("Should not close", result);
         }
-        return result;
     }
 
-    private Boolean waitForVideo(boolean expectSuccess) {
-        final Task<Boolean> video = new Task<>();
-        video.listen();
+    private void waitForVideoEnd(boolean expectSuccess) {
+        final Task<Boolean> video = new Task<>(true);
         doEndTask(video, true).when(listener).onVideoTaken(any(File.class));
-        Boolean result = video.await(2000);
+        Boolean result = video.await(8000);
         if (expectSuccess) {
             assertNotNull("Can take video", result);
         } else {
             assertNull("Should not take video", result);
         }
-        return result;
     }
 
     private byte[] waitForPicture(boolean expectSuccess) {
-        final Task<byte[]> pic = new Task<>();
-        pic.listen();
+        final Task<byte[]> pic = new Task<>(true);
         doEndTask(pic, 0).when(listener).onPictureTaken(any(byte[].class));
         byte[] result = pic.await(5000);
         if (expectSuccess) {
@@ -128,33 +141,40 @@ public class IntegrationTest extends BaseTest {
         return result;
     }
 
+    private void waitForVideoStart() {
+        controller.mStartVideoTask.listen();
+        camera.startCapturingVideo(null);
+        controller.mStartVideoTask.await(400);
+    }
+
+    private void waitForVideoQuality(VideoQuality quality) {
+        controller.mVideoQualityTask.listen();
+        camera.setVideoQuality(quality);
+        controller.mVideoQualityTask.await(400);
+    }
+
     //region test open/close
 
-    //-@Test
+    @Test
     public void testOpenClose() throws Exception {
         // Starting and stopping are hard to get since they happen on another thread.
         assertEquals(controller.getState(), CameraController.STATE_STOPPED);
 
-        camera.start();
         waitForOpen(true);
         assertEquals(controller.getState(), CameraController.STATE_STARTED);
 
-        camera.stop();
         waitForClose(true);
         assertEquals(controller.getState(), CameraController.STATE_STOPPED);
     }
 
-    //-@Test
+    @Test
     public void testOpenTwice() {
-        camera.start();
         waitForOpen(true);
-        camera.start();
         waitForOpen(false);
     }
 
-    //-@Test
+    @Test
     public void testCloseTwice() {
-        camera.stop();
         waitForClose(false);
     }
 
@@ -180,7 +200,6 @@ public class IntegrationTest extends BaseTest {
     public void testStartInitializesOptions() {
         assertNull(camera.getCameraOptions());
         assertNull(camera.getExtraProperties());
-        camera.start();
         waitForOpen(true);
         assertNotNull(camera.getCameraOptions());
         assertNotNull(camera.getExtraProperties());
@@ -193,7 +212,6 @@ public class IntegrationTest extends BaseTest {
 
     @Test
     public void testSetFacing() throws Exception {
-        camera.start();
         CameraOptions o = waitForOpen(true);
         int size = o.getSupportedFacing().size();
         if (size > 1) {
@@ -212,7 +230,6 @@ public class IntegrationTest extends BaseTest {
     @Test
     public void testSetSessionType() throws Exception {
         camera.setSessionType(SessionType.PICTURE);
-        camera.start();
         waitForOpen(true);
 
         // set session type should call stop and start again.
@@ -234,34 +251,47 @@ public class IntegrationTest extends BaseTest {
 
     @Test
     public void testSetZoom() {
-        camera.start();
         CameraOptions options = waitForOpen(true);
-        boolean can = options.isZoomSupported();
+
+        controller.mZoomTask.listen();
         float oldValue = camera.getZoom();
         float newValue = 0.65f;
         camera.setZoom(newValue);
-        assertEquals(can ? newValue : oldValue, camera.getZoom(), 0f);
+        controller.mZoomTask.await(500);
+
+        if (options.isZoomSupported()) {
+            assertEquals(newValue, camera.getZoom(), 0f);
+        } else {
+            assertEquals(oldValue, camera.getZoom(), 0f);
+        }
     }
 
     @Test
     public void testSetExposureCorrection() {
-        camera.start();
         CameraOptions options = waitForOpen(true);
-        boolean can = options.isExposureCorrectionSupported();
+
+        controller.mExposureCorrectionTask.listen();
         float oldValue = camera.getExposureCorrection();
         float newValue = options.getExposureCorrectionMaxValue();
         camera.setExposureCorrection(newValue);
-        assertEquals(can ? newValue : oldValue, camera.getExposureCorrection(), 0f);
+        controller.mExposureCorrectionTask.await(300);
+
+        if (options.isExposureCorrectionSupported()) {
+            assertEquals(newValue, camera.getExposureCorrection(), 0f);
+        } else {
+            assertEquals(oldValue, camera.getExposureCorrection(), 0f);
+        }
     }
 
     @Test
     public void testSetFlash() {
-        camera.start();
         CameraOptions options = waitForOpen(true);
         Flash[] values = Flash.values();
         Flash oldValue = camera.getFlash();
         for (Flash value : values) {
+            controller.mFlashTask.listen();
             camera.setFlash(value);
+            controller.mFlashTask.await(300);
             if (options.supports(value)) {
                 assertEquals(camera.getFlash(), value);
                 oldValue = value;
@@ -273,12 +303,13 @@ public class IntegrationTest extends BaseTest {
 
     @Test
     public void testSetWhiteBalance() {
-        camera.start();
         CameraOptions options = waitForOpen(true);
         WhiteBalance[] values = WhiteBalance.values();
         WhiteBalance oldValue = camera.getWhiteBalance();
         for (WhiteBalance value : values) {
+            controller.mWhiteBalanceTask.listen();
             camera.setWhiteBalance(value);
+            controller.mWhiteBalanceTask.await(300);
             if (options.supports(value)) {
                 assertEquals(camera.getWhiteBalance(), value);
                 oldValue = value;
@@ -290,12 +321,13 @@ public class IntegrationTest extends BaseTest {
 
     @Test
     public void testSetHdr() {
-        camera.start();
         CameraOptions options = waitForOpen(true);
         Hdr[] values = Hdr.values();
         Hdr oldValue = camera.getHdr();
         for (Hdr value : values) {
+            controller.mHdrTask.listen();
             camera.setHdr(value);
+            controller.mHdrTask.await(300);
             if (options.supports(value)) {
                 assertEquals(camera.getHdr(), value);
                 oldValue = value;
@@ -308,7 +340,6 @@ public class IntegrationTest extends BaseTest {
     @Test
     public void testSetAudio() {
         // TODO: when permissions are managed, check that Audio.ON triggers the audio permission
-        camera.start();
         waitForOpen(true);
         Audio[] values = Audio.values();
         for (Audio value : values) {
@@ -319,9 +350,10 @@ public class IntegrationTest extends BaseTest {
 
     @Test
     public void testSetLocation() {
-        camera.start();
         waitForOpen(true);
+        controller.mLocationTask.listen();
         camera.setLocation(10d, 2d);
+        controller.mLocationTask.await(300);
         assertNotNull(camera.getLocation());
         assertEquals(camera.getLocation().getLatitude(), 10d, 0d);
         assertEquals(camera.getLocation().getLongitude(), 2d, 0d);
@@ -333,38 +365,39 @@ public class IntegrationTest extends BaseTest {
     //region testSetVideoQuality
     // This can be tricky because can trigger layout changes.
 
-    // TODO: @Test(expected = IllegalStateException.class)
-    // Can't run on Travis, MediaRecorder not supported.
-    // Error while starting MediaRecorder. java.lang.RuntimeException: start failed.
-    public void testSetVideoQuality_whileRecording() {
+    @Test(expected = RuntimeException.class)
+    public void testSetVideoQuality_whileRecording() throws Throwable {
+        // Can't run on Travis, MediaRecorder not supported.
+        // Error while starting MediaRecorder. java.lang.RuntimeException: start failed.
         camera.setSessionType(SessionType.VIDEO);
-        camera.setVideoQuality(VideoQuality.HIGHEST);
-        camera.start();
+        waitForVideoQuality(VideoQuality.HIGHEST);
         waitForOpen(true);
-        camera.startCapturingVideo(null);
-        camera.setVideoQuality(VideoQuality.LOWEST);
+        waitForVideoStart();
+        waitForVideoQuality(VideoQuality.LOWEST);
+        waitForUiException();
     }
 
     @Test
     public void testSetVideoQuality_whileInPictureSessionType() {
         camera.setSessionType(SessionType.PICTURE);
-        camera.setVideoQuality(VideoQuality.HIGHEST);
-        camera.start();
+        waitForVideoQuality(VideoQuality.HIGHEST);
         waitForOpen(true);
-        camera.setVideoQuality(VideoQuality.LOWEST);
+        waitForVideoQuality(VideoQuality.LOWEST);
         assertEquals(camera.getVideoQuality(), VideoQuality.LOWEST);
     }
 
     @Test
     public void testSetVideoQuality_whileNotStarted() {
-        camera.setVideoQuality(VideoQuality.HIGHEST);
+        waitForVideoQuality(VideoQuality.HIGHEST);
         assertEquals(camera.getVideoQuality(), VideoQuality.HIGHEST);
-        camera.setVideoQuality(VideoQuality.LOWEST);
+
+        waitForVideoQuality(VideoQuality.LOWEST);
         assertEquals(camera.getVideoQuality(), VideoQuality.LOWEST);
     }
 
     @Test
     public void testSetVideoQuality_shouldRecompute() {
+        // TODO:
         // If video quality changes bring to a new capture size,
         // this might bring to a new aspect ratio,
         // which might bring to a new preview size. No idea how to test.
@@ -375,36 +408,34 @@ public class IntegrationTest extends BaseTest {
 
     //region test startVideo
 
-    // TODO: @Test(expected = IllegalStateException.class)
-    // Fails on Travis. Some emulators can't deal with MediaRecorder
-    // Error while starting MediaRecorder. java.lang.RuntimeException: start failed.
-    // as documented. This works locally though.
-    public void testStartVideo_whileInPictureMode() {
+    @Test(expected = RuntimeException.class)
+    public void testStartVideo_whileInPictureMode() throws Throwable {
+        // Fails on Travis. Some emulators can't deal with MediaRecorder
+        // Error while starting MediaRecorder. java.lang.RuntimeException: start failed.
+        // as documented. This works locally though.
         camera.setSessionType(SessionType.PICTURE);
-        camera.start();
         waitForOpen(true);
-        camera.startCapturingVideo(null);
+        waitForVideoStart();
+        waitForUiException();
     }
 
-    // TODO: @Test
-    // Fails on Travis. Some emulators can't deal with MediaRecorder,
-    // Error while starting MediaRecorder. java.lang.RuntimeException: start failed.
-    // as documented. This works locally though.
+    @Test
     public void testStartEndVideo() {
+        // Fails on Travis. Some emulators can't deal with MediaRecorder,
+        // Error while starting MediaRecorder. java.lang.RuntimeException: start failed.
+        // as documented. This works locally though.
         camera.setSessionType(SessionType.VIDEO);
-        camera.start();
         waitForOpen(true);
-        camera.startCapturingVideo(null, 1000);
-        waitForVideo(true); // waits 2000
+        camera.startCapturingVideo(null, 4000);
+        waitForVideoEnd(true);
     }
 
     @Test
     public void testEndVideo_withoutStarting() {
         camera.setSessionType(SessionType.VIDEO);
-        camera.start();
         waitForOpen(true);
         camera.stopCapturingVideo();
-        waitForVideo(false);
+        waitForVideoEnd(false);
     }
 
     //endregion
@@ -414,13 +445,18 @@ public class IntegrationTest extends BaseTest {
 
     @Test
     public void testStartAutoFocus() {
-        camera.start();
         CameraOptions o = waitForOpen(true);
+
+        final Task<PointF> focus = new Task<>(true);
+        doEndTask(focus, 0).when(listener).onFocusStart(any(PointF.class));
+
         camera.startAutoFocus(1, 1);
+        PointF point = focus.await(300);
         if (o.isAutoFocusSupported()) {
-            verify(listener, times(1)).onFocusStart(new PointF(1, 1));
+            assertNotNull(point);
+            assertEquals(point, new PointF(1, 1));
         } else {
-            verify(listener, never()).onFocusStart(any(PointF.class));
+            assertNull(point);
         }
     }
 
@@ -437,7 +473,6 @@ public class IntegrationTest extends BaseTest {
     @Test
     public void testCapturePicture_concurrentCalls() throws Exception {
         // Second take should fail.
-        camera.start();
         waitForOpen(true);
 
         CountDownLatch latch = new CountDownLatch(2);
@@ -453,7 +488,6 @@ public class IntegrationTest extends BaseTest {
     @Test
     public void testCapturePicture_size() throws Exception {
         camera.setCropOutput(false);
-        camera.start();
         waitForOpen(true);
 
         Size size = camera.getCaptureSize();
@@ -475,7 +509,6 @@ public class IntegrationTest extends BaseTest {
     @Test
     public void testCaptureSnapshot_concurrentCalls() throws Exception {
         // Second take should fail.
-        camera.start();
         waitForOpen(true);
 
         CountDownLatch latch = new CountDownLatch(2);
@@ -483,15 +516,14 @@ public class IntegrationTest extends BaseTest {
 
         camera.captureSnapshot();
         camera.captureSnapshot();
-        boolean did = latch.await(4, TimeUnit.SECONDS);
+        boolean did = latch.await(6, TimeUnit.SECONDS);
         assertFalse(did);
-        assertEquals(latch.getCount(), 1);
+        assertEquals(1, latch.getCount());
     }
 
     @Test
     public void testCaptureSnapshot_size() throws Exception {
         camera.setCropOutput(false);
-        camera.start();
         waitForOpen(true);
 
         Size size = camera.getPreviewSize();
@@ -520,7 +552,6 @@ public class IntegrationTest extends BaseTest {
     public void testFrameProcessing_simple() throws Exception {
         FrameProcessor processor = mock(FrameProcessor.class);
         camera.addFrameProcessor(processor);
-        camera.start();
         waitForOpen(true);
 
         assert30Frames(processor);
@@ -530,7 +561,6 @@ public class IntegrationTest extends BaseTest {
     public void testFrameProcessing_afterSnapshot() throws Exception {
         FrameProcessor processor = mock(FrameProcessor.class);
         camera.addFrameProcessor(processor);
-        camera.start();
         waitForOpen(true);
 
         // In Camera1, snapshots will clear the preview callback
@@ -545,11 +575,8 @@ public class IntegrationTest extends BaseTest {
     public void testFrameProcessing_afterRestart() throws Exception {
         FrameProcessor processor = mock(FrameProcessor.class);
         camera.addFrameProcessor(processor);
-        camera.start();
         waitForOpen(true);
-        camera.stop();
         waitForClose(true);
-        camera.start();
         waitForOpen(true);
 
         assert30Frames(processor);

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

@@ -32,23 +32,23 @@ public class MockCameraController extends CameraController {
     }
 
     @Override
-    void onStart() throws Exception {
+    void onStart() {
     }
 
     @Override
-    void onStop() throws Exception {
+    void onStop() {
     }
 
     @Override
-    boolean setZoom(float zoom) {
+    void setZoom(float zoom, PointF[] points, boolean notify) {
+        mZoomValue = zoom;
         mZoomChanged = true;
-        return true;
     }
 
     @Override
-    boolean setExposureCorrection(float EVvalue) {
+    void setExposureCorrection(float EVvalue, float[] bounds, PointF[] points, boolean notify) {
+        mExposureCorrectionValue = EVvalue;
         mExposureCorrectionChanged = true;
-        return true;
     }
 
     @Override
@@ -92,24 +92,20 @@ public class MockCameraController extends CameraController {
     }
 
     @Override
-    boolean capturePicture() {
+    void capturePicture() {
         mPictureCaptured = true;
-        return true;
     }
 
     @Override
-    boolean captureSnapshot() {
-        return true;
+    void captureSnapshot() {
     }
 
     @Override
-    boolean startVideo(@NonNull File file) {
-        return true;
+    void startVideo(@NonNull File file) {
     }
 
     @Override
-    boolean endVideo() {
-        return true;
+    void endVideo() {
     }
 
     @Override
@@ -120,23 +116,19 @@ public class MockCameraController extends CameraController {
 
 
     @Override
-    boolean startAutoFocus(@Nullable Gesture gesture, PointF point) {
+    void startAutoFocus(@Nullable Gesture gesture, PointF point) {
         mFocusStarted = true;
-        return true;
     }
 
     @Override
     public void onSurfaceChanged() {
-
     }
 
     @Override
     public void onSurfaceAvailable() {
-
     }
 
     @Override
     public void onBufferAvailable(byte[] buffer) {
-
     }
 }

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

@@ -31,8 +31,7 @@ public abstract class PreviewTest extends BaseTest {
 
     @Before
     public void setUp() {
-        availability = new Task<>();
-        availability.listen();
+        availability = new Task<>(true);
 
         ui(new Runnable() {
             @Override

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

@@ -24,8 +24,7 @@ public class WorkerHandlerTest extends BaseTest {
 
     @Test
     public void testStaticRun() {
-        final Task<Boolean> task = new Task<>();
-        task.listen();
+        final Task<Boolean> task = new Task<>(true);
         Runnable action = new Runnable() {
             @Override
             public void run() {

cameraview/src/main/java/com/otaliastudios/cameraview/Camera2.java

@@ -37,12 +37,12 @@ class Camera2 extends CameraController {
     }
 
     @Override
-    void onStart() throws Exception {
+    void onStart() {
 
     }
 
     @Override
-    void onStop() throws Exception {
+    void onStop() {
 
     }
 
@@ -57,13 +57,13 @@ class Camera2 extends CameraController {
     }
 
     @Override
-    boolean setZoom(float zoom) {
-        return false;
+    void setZoom(float zoom, PointF[] points, boolean notify) {
+
     }
 
     @Override
-    boolean setExposureCorrection(float EVvalue) {
-        return false;
+    void setExposureCorrection(float EVvalue, float[] bounds, PointF[] points, boolean notify) {
+
     }
 
     @Override
@@ -97,23 +97,23 @@ class Camera2 extends CameraController {
     }
 
     @Override
-    boolean capturePicture() {
-        return false;
+    void capturePicture() {
+
     }
 
     @Override
-    boolean captureSnapshot() {
-        return false;
+    void captureSnapshot() {
+
     }
 
     @Override
-    boolean startVideo(@NonNull File file) {
-        return false;
+    void startVideo(@NonNull File file) {
+
     }
 
     @Override
-    boolean endVideo() {
-        return false;
+    void endVideo() {
+
     }
 
     @Override
@@ -122,8 +122,8 @@ class Camera2 extends CameraController {
     }
 
     @Override
-    boolean startAutoFocus(@Nullable Gesture gesture, PointF point) {
-        return false;
+    void startAutoFocus(@Nullable Gesture gesture, PointF point) {
+
     }
 
     @Override

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

@@ -2,13 +2,18 @@ package com.otaliastudios.cameraview;
 
 import android.graphics.PointF;
 import android.location.Location;
+import android.os.Handler;
+import android.os.Looper;
 import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
 import android.support.annotation.WorkerThread;
 
 import java.io.File;
 
-abstract class CameraController implements CameraPreview.SurfaceCallback, FrameManager.BufferCallback {
+abstract class CameraController implements
+        CameraPreview.SurfaceCallback,
+        FrameManager.BufferCallback,
+        Thread.UncaughtExceptionHandler {
 
     private static final String TAG = CameraController.class.getSimpleName();
     private static final CameraLogger LOG = CameraLogger.create(TAG);
@@ -20,6 +25,8 @@ abstract class CameraController implements CameraPreview.SurfaceCallback, FrameM
 
     protected final CameraView.CameraCallbacks mCameraCallbacks;
     protected CameraPreview mPreview;
+    protected WorkerHandler mHandler;
+    /* for tests */ Handler mCrashHandler;
 
     protected Facing mFacing;
     protected Flash mFlash;
@@ -30,6 +37,9 @@ abstract class CameraController implements CameraPreview.SurfaceCallback, FrameM
     protected Location mLocation;
     protected Audio mAudio;
 
+    protected float mZoomValue;
+    protected float mExposureCorrectionValue;
+
     protected Size mCaptureSize;
     protected Size mPreviewSize;
     protected int mPreviewFormat;
@@ -40,34 +50,23 @@ abstract class CameraController implements CameraPreview.SurfaceCallback, FrameM
 
     protected int mDisplayOffset;
     protected int mDeviceOrientation;
-
-    protected boolean mScheduledForStart = false;
-    protected boolean mScheduledForStop = false;
-    protected boolean mScheduledForRestart = false;
     protected int mState = STATE_STOPPED;
 
-    protected WorkerHandler mHandler;
+    // Used for testing.
+    Task<Void> mZoomTask = new Task<>();
+    Task<Void> mExposureCorrectionTask = new Task<>();
+    Task<Void> mFlashTask = new Task<>();
+    Task<Void> mWhiteBalanceTask = new Task<>();
+    Task<Void> mHdrTask = new Task<>();
+    Task<Void> mLocationTask = new Task<>();
+    Task<Void> mVideoQualityTask = new Task<>();
+    Task<Void> mStartVideoTask = new Task<>();
 
     CameraController(CameraView.CameraCallbacks callback) {
         mCameraCallbacks = callback;
+        mCrashHandler = new Handler(Looper.getMainLooper());
         mHandler = WorkerHandler.get("CameraViewController");
-        mHandler.getThread().setUncaughtExceptionHandler(new Thread.UncaughtExceptionHandler() {
-            @Override
-            public void uncaughtException(Thread thread, Throwable throwable) {
-                // Something went wrong. Thread is terminated (about to?).
-                // Move to other thread and stop resources.
-                LOG.w("Interrupting thread, due to exception.", throwable);
-                thread.interrupt();
-                LOG.w("Interrupted thread. Posting a stopImmediately.", ss());
-                mHandler = WorkerHandler.get("CameraViewController");
-                mHandler.post(new Runnable() {
-                    @Override
-                    public void run() {
-                        stopImmediately();
-                    }
-                });
-            }
-        });
+        mHandler.getThread().setUncaughtExceptionHandler(this);
         mFrameManager = new FrameManager(2, this);
     }
 
@@ -76,6 +75,58 @@ abstract class CameraController implements CameraPreview.SurfaceCallback, FrameM
         mPreview.setSurfaceCallback(this);
     }
 
+    //region Error handling
+
+    @Override
+    public void uncaughtException(final Thread thread, final Throwable throwable) {
+        // Something went wrong. Thread is terminated (about to?).
+        // Move to other thread and release resources.
+        if (!(throwable instanceof CameraException)) {
+            // This is unexpected, either a bug or something the developer should know.
+            // Release and crash the UI thread so we get bug reports.
+            LOG.e("uncaughtException:", "Unexpected exception:", throwable);
+            destroy();
+            mCrashHandler.post(new Runnable() {
+                @Override
+                public void run() {
+                    RuntimeException exception;
+                    if (throwable instanceof RuntimeException) {
+                        exception = (RuntimeException) throwable;
+                    } else {
+                        exception = new RuntimeException(throwable);
+                    }
+                    throw exception;
+                }
+            });
+        } else {
+            // At the moment all CameraExceptions are unrecoverable, there was something
+            // wrong when starting, stopping, or binding the camera to the preview.
+            final CameraException error = (CameraException) throwable;
+            LOG.e("uncaughtException:", "Interrupting thread with state:", ss(), "due to CameraException:", error);
+            thread.interrupt();
+            mHandler = WorkerHandler.get("CameraViewController");
+            mHandler.getThread().setUncaughtExceptionHandler(this);
+            LOG.i("uncaughtException:", "Calling stopImmediately and notifying.");
+            mHandler.post(new Runnable() {
+                @Override
+                public void run() {
+                    stopImmediately();
+                    mCameraCallbacks.dispatchError(error);
+                }
+            });
+        }
+    }
+
+    final void destroy() {
+        LOG.i("destroy:", "state:", ss());
+        // Prevent CameraController leaks.
+        mHandler.getThread().setUncaughtExceptionHandler(null);
+        // Stop if needed.
+        stopImmediately();
+    }
+
+    //endregion
+
     //region Start&Stop
 
     private String ss() {
@@ -91,25 +142,17 @@ abstract class CameraController implements CameraPreview.SurfaceCallback, FrameM
     // Starts the preview asynchronously.
     final void start() {
         LOG.i("Start:", "posting runnable. State:", ss());
-        mScheduledForStart = true;
         mHandler.post(new Runnable() {
             @Override
             public void run() {
-                try {
-                    LOG.i("Start:", "executing. State:", ss());
-                    mScheduledForStart = false;
-                    if (mState >= STATE_STARTING) return;
-                    mState = STATE_STARTING;
-                    LOG.i("Start:", "about to call onStart()", ss());
-                    onStart();
-                    LOG.i("Start:", "returned from onStart().", "Dispatching.", ss());
-                    mState = STATE_STARTED;
-                    mCameraCallbacks.dispatchOnCameraOpened(mOptions);
-
-                } catch (Exception e) {
-                    LOG.e("Error while starting the camera engine.", e);
-                    throw new RuntimeException(e);
-                }
+                LOG.i("Start:", "executing. State:", ss());
+                if (mState >= STATE_STARTING) return;
+                mState = STATE_STARTING;
+                LOG.i("Start:", "about to call onStart()", ss());
+                onStart();
+                LOG.i("Start:", "returned from onStart().", "Dispatching.", ss());
+                mState = STATE_STARTED;
+                mCameraCallbacks.dispatchOnCameraOpened(mOptions);
             }
         });
     }
@@ -117,43 +160,34 @@ abstract class CameraController implements CameraPreview.SurfaceCallback, FrameM
     // Stops the preview asynchronously.
     final void stop() {
         LOG.i("Stop:", "posting runnable. State:", ss());
-        mScheduledForStop = true;
         mHandler.post(new Runnable() {
             @Override
             public void run() {
-                try {
-                    LOG.i("Stop:", "executing. State:", ss());
-                    mScheduledForStop = false;
-                    if (mState <= STATE_STOPPED) return;
-                    mState = STATE_STOPPING;
-                    LOG.i("Stop:", "about to call onStop()");
-                    onStop();
-                    LOG.i("Stop:", "returned from onStop().", "Dispatching.");
-                    mState = STATE_STOPPED;
-                    mCameraCallbacks.dispatchOnCameraClosed();
-
-                } catch (Exception e) {
-                    LOG.e("Error while stopping the camera engine.", e);
-                    throw new RuntimeException(e);
-                }
+                LOG.i("Stop:", "executing. State:", ss());
+                if (mState <= STATE_STOPPED) return;
+                mState = STATE_STOPPING;
+                LOG.i("Stop:", "about to call onStop()");
+                onStop();
+                LOG.i("Stop:", "returned from onStop().", "Dispatching.");
+                mState = STATE_STOPPED;
+                mCameraCallbacks.dispatchOnCameraClosed();
             }
         });
     }
 
     // Stops the preview synchronously, ensuring no exceptions are thrown.
-    void stopImmediately() {
+    final void stopImmediately() {
         try {
             // Don't check, try stop again.
-            LOG.i("Stop immediately. State was:", ss());
+            LOG.i("stopImmediately:", "State was:", ss());
+            if (mState == STATE_STOPPED) return;
             mState = STATE_STOPPING;
-            // Prevent leaking CameraController.
-            mHandler.getThread().setUncaughtExceptionHandler(null);
             onStop();
             mState = STATE_STOPPED;
-            LOG.i("Stop immediately. Stopped. State is:", ss());
+            LOG.i("stopImmediately:", "Stopped. State is:", ss());
         } catch (Exception e) {
             // Do nothing.
-            LOG.i("Stop immediately. Exception while stopping.", e);
+            LOG.i("stopImmediately:", "Swallowing exception while stopping.", e);
             mState = STATE_STOPPED;
         }
     }
@@ -161,34 +195,25 @@ abstract class CameraController implements CameraPreview.SurfaceCallback, FrameM
     // Forces a restart.
     protected final void restart() {
         LOG.i("Restart:", "posting runnable");
-        mScheduledForRestart = true;
         mHandler.post(new Runnable() {
             @Override
             public void run() {
-                try {
-                    LOG.i("Restart:", "executing. Needs stopping:", mState > STATE_STOPPED, ss());
-                    mScheduledForRestart = false;
-                    // Don't stop if stopped.
-                    if (mState > STATE_STOPPED) {
-                        mState = STATE_STOPPING;
-                        onStop();
-                        mState = STATE_STOPPED;
-                        LOG.i("Restart:", "stopped. Dispatching.", ss());
-                        mCameraCallbacks.dispatchOnCameraClosed();
-                    }
-
-                    LOG.i("Restart: about to start. State:", ss());
-                    mState = STATE_STARTING;
-                    onStart();
-                    mState = STATE_STARTED;
-                    LOG.i("Restart: returned from start. Dispatching. State:", ss());
-                    mCameraCallbacks.dispatchOnCameraOpened(mOptions);
-
-                } catch (Exception e) {
-                    LOG.e("Error while restarting the camera engine.", e);
-                    throw new RuntimeException(e);
-
+                LOG.i("Restart:", "executing. Needs stopping:", mState > STATE_STOPPED, ss());
+                // Don't stop if stopped.
+                if (mState > STATE_STOPPED) {
+                    mState = STATE_STOPPING;
+                    onStop();
+                    mState = STATE_STOPPED;
+                    LOG.i("Restart:", "stopped. Dispatching.", ss());
+                    mCameraCallbacks.dispatchOnCameraClosed();
                 }
+
+                LOG.i("Restart: about to start. State:", ss());
+                mState = STATE_STARTING;
+                onStart();
+                mState = STATE_STARTED;
+                LOG.i("Restart: returned from start. Dispatching. State:", ss());
+                mCameraCallbacks.dispatchOnCameraOpened(mOptions);
             }
         });
     }
@@ -196,11 +221,11 @@ abstract class CameraController implements CameraPreview.SurfaceCallback, FrameM
     // Starts the preview.
     // At the end of this method camera must be available, e.g. for setting parameters.
     @WorkerThread
-    abstract void onStart() throws Exception;
+    abstract void onStart();
 
     // Stops the preview.
     @WorkerThread
-    abstract void onStop() throws Exception;
+    abstract void onStop();
 
     // Returns current state.
     final int getState() {
@@ -231,11 +256,11 @@ abstract class CameraController implements CameraPreview.SurfaceCallback, FrameM
     // Should restart the session if active.
     abstract void setFacing(Facing facing);
 
-    // If opened and supported, apply and return true.
-    abstract boolean setZoom(float zoom);
+    // If closed, no-op. If opened, check supported and apply.
+    abstract void setZoom(float zoom, PointF[] points, boolean notify);
 
-    // If opened and supported, apply and return true.
-    abstract boolean setExposureCorrection(float EVvalue);
+    // If closed, no-op. If opened, check supported and apply.
+    abstract void setExposureCorrection(float EVvalue, float[] bounds, PointF[] points, boolean notify);
 
     // If closed, keep. If opened, check supported and apply.
     abstract void setFlash(Flash flash);
@@ -260,17 +285,17 @@ abstract class CameraController implements CameraPreview.SurfaceCallback, FrameM
 
     //region APIs
 
-    abstract boolean capturePicture();
+    abstract void capturePicture();
 
-    abstract boolean captureSnapshot();
+    abstract void captureSnapshot();
 
-    abstract boolean startVideo(@NonNull File file);
+    abstract void startVideo(@NonNull File file);
 
-    abstract boolean endVideo();
+    abstract void endVideo();
 
     abstract boolean shouldFlipSizes(); // Wheter the Sizes should be flipped to match the view orientation.
 
-    abstract boolean startAutoFocus(@Nullable Gesture gesture, PointF point);
+    abstract void startAutoFocus(@Nullable Gesture gesture, PointF point);
 
     //endregion
 
@@ -318,6 +343,14 @@ abstract class CameraController implements CameraPreview.SurfaceCallback, FrameM
         return mAudio;
     }
 
+    final float getZoomValue() {
+        return mZoomValue;
+    }
+
+    final float getExposureCorrectionValue() {
+        return mExposureCorrectionValue;
+    }
+
     final Size getCaptureSize() {
         return mCaptureSize;
     }

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

@@ -0,0 +1,12 @@
+package com.otaliastudios.cameraview;
+
+
+/**
+ * Holds an error with the camera configuration.
+ */
+public class CameraException extends RuntimeException {
+
+    CameraException(Throwable cause) {
+        super(cause);
+    }
+}

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

@@ -1,6 +1,7 @@
 package com.otaliastudios.cameraview;
 
 import android.graphics.PointF;
+import android.support.annotation.NonNull;
 import android.support.annotation.UiThread;
 
 import java.io.File;
@@ -29,6 +30,25 @@ public abstract class CameraListener {
     }
 
 
+    /**
+     * Notifies about an error during the camera setup or configuration.
+     * At the moment, errors that are passed here are unrecoverable. When this is called,
+     * the camera has been released and is presumably showing a black preview.
+     *
+     * This is the right moment to show an error dialog to the user.
+     * You can try calling start() again, but that is not guaranteed to work - if it doesn't,
+     * this callback will be invoked again.
+     *
+     * In the future, more information will be passed through the {@link CameraException} instance.
+     *
+     * @param exception the error
+     */
+    @UiThread
+    public void onCameraError(@NonNull CameraException exception) {
+
+    }
+
+
     /**
      * Notifies that a picture previously captured with {@link CameraView#capturePicture()}
      * or {@link CameraView#captureSnapshot()} is ready to be shown or saved.
@@ -78,8 +98,8 @@ public abstract class CameraListener {
 
     /**
      * Notifies that user interacted with the screen and started focus with a gesture,
-     * and the autofocus is trying to focus around that area.
-     * This can be used to draw things on screen.
+     * and the autofocus is trying to focus around that area. This can be used to draw things on screen.
+     * Can also be triggered by {@link CameraView#startAutoFocus(float, float)}.
      *
      * @param point coordinates with respect to CameraView.getWidth() and CameraView.getHeight()
      */
@@ -93,6 +113,7 @@ public abstract class CameraListener {
      * Notifies that a gesture focus event just ended, and the camera converged
      * to a new focus (and possibly exposure and white balance).
      * This might succeed or not.
+     * Can also be triggered by {@link CameraView#startAutoFocus(float, float)}.
      *
      * @param successful whether camera succeeded
      * @param point coordinates with respect to CameraView.getWidth() and CameraView.getHeight()

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

@@ -52,8 +52,6 @@ public class CameraView extends FrameLayout {
     // Self managed parameters
     private int mJpegQuality;
     private boolean mCropOutput;
-    private float mZoomValue;
-    private float mExposureCorrectionValue;
     private boolean mPlaySounds;
     private HashMap<Gesture, GestureAction> mGestureMap = new HashMap<>(4);
 
@@ -448,7 +446,7 @@ public class CameraView extends FrameLayout {
     // Some gesture layout detected a gesture. It's not known at this moment:
     // (1) if it was mapped to some action (we check here)
     // (2) if it's supported by the camera (CameraController checks)
-    private boolean onGesture(GestureLayout source, @NonNull CameraOptions options) {
+    private void onGesture(GestureLayout source, @NonNull CameraOptions options) {
         Gesture gesture = source.getGestureType();
         GestureAction action = mGestureMap.get(gesture);
         PointF[] points = source.getPoints();
@@ -456,36 +454,29 @@ public class CameraView extends FrameLayout {
         switch (action) {
 
             case CAPTURE:
-                return mCameraController.capturePicture();
+                mCameraController.capturePicture();
+                break;
 
             case FOCUS:
             case FOCUS_WITH_MARKER:
-                return mCameraController.startAutoFocus(gesture, points[0]);
+                mCameraController.startAutoFocus(gesture, points[0]);
+                break;
 
             case ZOOM:
-                oldValue = mZoomValue;
+                oldValue = mCameraController.getZoomValue();
                 newValue = source.scaleValue(oldValue, 0, 1);
-                if (mCameraController.setZoom(newValue)) {
-                    mZoomValue = newValue;
-                    mCameraCallbacks.dispatchOnZoomChanged(newValue, points);
-                    return true;
-                }
+                mCameraController.setZoom(newValue, points, true);
                 break;
 
             case EXPOSURE_CORRECTION:
-                oldValue = mExposureCorrectionValue;
+                oldValue = mCameraController.getExposureCorrectionValue();
                 float minValue = options.getExposureCorrectionMinValue();
                 float maxValue = options.getExposureCorrectionMaxValue();
                 newValue = source.scaleValue(oldValue, minValue, maxValue);
                 float[] bounds = new float[]{minValue, maxValue};
-                if (mCameraController.setExposureCorrection(newValue)) {
-                    mExposureCorrectionValue = newValue;
-                    mCameraCallbacks.dispatchOnExposureCorrectionChanged(newValue, bounds, points);
-                    return true;
-                }
+                mCameraController.setExposureCorrection(newValue, bounds, points, true);
                 break;
         }
-        return false;
     }
 
     //endregion
@@ -589,7 +580,7 @@ public class CameraView extends FrameLayout {
     public void destroy() {
         clearCameraListeners();
         clearFrameProcessors();
-        mCameraController.stopImmediately();
+        mCameraController.destroy();
     }
 
     //endregion
@@ -640,9 +631,7 @@ public class CameraView extends FrameLayout {
             float max = options.getExposureCorrectionMaxValue();
             if (EVvalue < min) EVvalue = min;
             if (EVvalue > max) EVvalue = max;
-            if (mCameraController.setExposureCorrection(EVvalue)) {
-                mExposureCorrectionValue = EVvalue;
-            }
+            mCameraController.setExposureCorrection(EVvalue, null, null, false);
         }
     }
 
@@ -653,7 +642,7 @@ public class CameraView extends FrameLayout {
      * @return the current exposure correction value
      */
     public float getExposureCorrection() {
-        return mExposureCorrectionValue;
+        return mCameraController.getExposureCorrectionValue();
     }
 
 
@@ -670,9 +659,7 @@ public class CameraView extends FrameLayout {
     public void setZoom(float zoom) {
         if (zoom < 0) zoom = 0;
         if (zoom > 1) zoom = 1;
-        if (mCameraController.setZoom(zoom)) {
-            mZoomValue = zoom;
-        }
+        mCameraController.setZoom(zoom, null, false);
     }
 
 
@@ -681,7 +668,7 @@ public class CameraView extends FrameLayout {
      * @return the current zoom value
      */
     public float getZoom() {
-        return mZoomValue;
+        return mCameraController.getZoomValue();
     }
 
 
@@ -1146,9 +1133,7 @@ public class CameraView extends FrameLayout {
      * @see #captureSnapshot()
      */
     public void capturePicture() {
-        if (mCameraController.capturePicture() && mPlaySounds) {
-            // TODO: playSound on Camera2
-        }
+        mCameraController.capturePicture();
     }
 
 
@@ -1163,10 +1148,7 @@ public class CameraView extends FrameLayout {
      * @see #capturePicture()
      */
     public void captureSnapshot() {
-        if (mCameraController.captureSnapshot() && mPlaySounds) {
-            //noinspection all
-            playSound(MediaActionSound.SHUTTER_CLICK);
-        }
+        mCameraController.captureSnapshot();
     }
 
 
@@ -1193,15 +1175,14 @@ public class CameraView extends FrameLayout {
         if (file == null) {
             file = new File(getContext().getFilesDir(), "video.mp4");
         }
-        if (mCameraController.startVideo(file)) {
-            mUiHandler.post(new Runnable() {
-                @Override
-                public void run() {
-                    mKeepScreenOn = getKeepScreenOn();
-                    if (!mKeepScreenOn) setKeepScreenOn(true);
-                }
-            });
-        }
+        mCameraController.startVideo(file);
+        mUiHandler.post(new Runnable() {
+            @Override
+            public void run() {
+                mKeepScreenOn = getKeepScreenOn();
+                if (!mKeepScreenOn) setKeepScreenOn(true);
+            }
+        });
     }
 
 
@@ -1238,14 +1219,13 @@ public class CameraView extends FrameLayout {
      * This will fire {@link CameraListener#onVideoTaken(File)}.
      */
     public void stopCapturingVideo() {
-        if (mCameraController.endVideo()) {
-            mUiHandler.post(new Runnable() {
-                @Override
-                public void run() {
-                    if (getKeepScreenOn() != mKeepScreenOn) setKeepScreenOn(mKeepScreenOn);
-                }
-            });
-        }
+        mCameraController.endVideo();
+        mUiHandler.post(new Runnable() {
+            @Override
+            public void run() {
+                if (getKeepScreenOn() != mKeepScreenOn) setKeepScreenOn(mKeepScreenOn);
+            }
+        });
     }
 
 
@@ -1346,6 +1326,7 @@ public class CameraView extends FrameLayout {
         void dispatchOnCameraOpened(CameraOptions options);
         void dispatchOnCameraClosed();
         void onCameraPreviewSizeChanged();
+        void onShutter(boolean shouldPlaySound);
         void processImage(byte[] jpeg, boolean consistentWithView, boolean flipHorizontally);
         void processSnapshot(YuvImage image, boolean consistentWithView, boolean flipHorizontally);
         void dispatchOnVideoTaken(File file);
@@ -1354,6 +1335,7 @@ public class CameraView extends FrameLayout {
         void dispatchOnZoomChanged(final float newValue, final PointF[] fingers);
         void dispatchOnExposureCorrectionChanged(float newValue, float[] bounds, PointF[] fingers);
         void dispatchFrame(Frame frame);
+        void dispatchError(CameraException exception);
     }
 
     private class Callbacks implements CameraCallbacks {
@@ -1408,6 +1390,13 @@ public class CameraView extends FrameLayout {
             });
         }
 
+        @Override
+        public void onShutter(boolean shouldPlaySound) {
+            if (shouldPlaySound && mPlaySounds) {
+                //noinspection all
+                playSound(MediaActionSound.SHUTTER_CLICK);
+            }
+        }
 
         /**
          * What would be great here is to ensure the EXIF tag in the jpeg is consistent with what we expect,
@@ -1620,11 +1609,20 @@ public class CameraView extends FrameLayout {
                 });
             }
         }
-    }
-
-    //endregion
 
-    //region Deprecated
+        @Override
+        public void dispatchError(final CameraException exception) {
+            mLogger.i("dispatchError", exception);
+            mUiHandler.post(new Runnable() {
+                @Override
+                public void run() {
+                    for (CameraListener listener : mListeners) {
+                        listener.onCameraError(exception);
+                    }
+                }
+            });
+        }
+    }
 
     //endregion
 }

cameraview/src/main/utils/com/otaliastudios/cameraview/Task.java

@@ -18,6 +18,10 @@ class Task<T> {
     Task() {
     }
 
+    Task(boolean startListening) {
+        if (startListening) listen();
+    }
+
     private boolean listening() {
         return mLatch != null;
     }

cameraview/src/test/java/com/otaliastudios/cameraview/CameraExceptionTest.java

@@ -0,0 +1,16 @@
+package com.otaliastudios.cameraview;
+
+
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+
+public class CameraExceptionTest {
+
+    @Test
+    public void testConstructor() {
+        RuntimeException cause = new RuntimeException("Error");
+        CameraException camera = new CameraException(cause);
+        assertEquals(cause, camera.getCause());
+    }
+}