Flashlight Control In Marshmallow

I have a problem regarding the camera in the most recent Marshmallow build, more specifically the flashlight. On any pre-Marshmallow version all I need to do to turn the flash on/o

Solution 1:

Google has introduced torchmode in OS 6 (Android M). if your purpose is only to turn on/off the flash, below code can help you with that:

privatestaticvoidhandleActionTurnOnFlashLight(Context context){
    try{

        CameraManager manager = (CameraManager) context.getSystemService(Context.CAMERA_SERVICE);
        String[] list = manager.getCameraIdList();
        manager.setTorchMode(list[0], true);
    }
    catch (CameraAccessException cae){
        Log.e(TAG, cae.getMessage());
        cae.printStackTrace();
    }
}

privatestaticvoidhandleActionTurnOffFlashLight(Context context){
    try{
        CameraManager manager = (CameraManager) context.getSystemService(Context.CAMERA_SERVICE);
        manager.setTorchMode(manager.getCameraIdList()[0], false);
    }
    catch (CameraAccessException cae){
        Log.e(TAG, cae.getMessage());
        cae.printStackTrace();
    }
}

All you have to do is: Get cameraid's list out of which camera ID zero(0) is your primary camera for which you want to turn flash on/off. Simply pass the cameraID to setTochMode API with boolean value for turning it on or off.

Do note that this piece of code will work only with OS 6, so you need to check for device OS and based upon that you need to select which API's to call for pre-marshmallow devices.

Kindly mark this as solution if it solves your problem.

Solution 2:

As Saurabh7474 has responded, to check the version of Android and use setTorchMode API it's very correct.

Although you can also use params.setFlashMode (...) in marshmallow using

mCamera.setPreviewTexture (newSurfaceTexture (100))

after Camera.open (...) and before calling mCamera.startPreview();

try {
                Log.i(TAG, "getCamera");
                int requestedCameraId = getIdForRequestedCamera(mFacing);
                if (requestedCameraId == -1) {
                    thrownewRuntimeException("Could not find requested camera.");
                }
                mCamera = Camera.open(requestedCameraId);
                mCamera.setPreviewTexture(new SurfaceTexture(DUMMY_TEXTURE_NAME));
                params = mCamera.getParameters();
            } catch (RuntimeException e) {
                Log.e("Failed to Open. Error:", e.getMessage());
            } catch (IOException e) {
                Log.e("Failed to Open. can't setPreviewTexture:", e.getMessage());
            }

then when you want, you can use

        mParams.setFlashMode(Camera.Parameters.FLASH_MODE_TORCH);
        camera.setParameters(mParams);

My answer is based on CameraSource examples of Vision API that uses params.setFlashMode (...) and works in Api 23 and above. If you decide to inspect CameraSource, the key method that has solved the same problem is "start ()", in the line 312 ...

https://github.com/googlesamples/android-vision/blob/master/visionSamples/barcode-reader/app/src/main/java/com/google/android/gms/samples/vision/barcodereader/ui/camera/CameraSource.java

The reason you can find here https://stackoverflow.com/a/33333046/4114846

Solution 3:

Update your app to check for permissions at runtime. You have to have android.permission.CAMERA granted. Including it in the manifest of your app is not going to grant it to you on Marshmallow. You'll need to detect whether or not it has been granted and request it.

Solution 4:

Building off of Saurabh7474's answer, you can toggle Marshmallow's torchMode by registering a torchCallback:

 final CameraManager mCameraManager = (CameraManager) getSystemService(Context.CAMERA_SERVICE);
 CameraManager.TorchCallback torchCallback = newCameraManager.TorchCallback() {
     @OverridepublicvoidonTorchModeUnavailable(String cameraId) {
         super.onTorchModeUnavailable(cameraId);
     }

     @OverridepublicvoidonTorchModeChanged(String cameraId, boolean enabled) {
         super.onTorchModeChanged(cameraId, enabled);
         boolean currentTorchState = enabled;
         try {
             mCameraManager.setTorchMode(cameraId, !currentTorchState);
         } catch (CameraAccessException e){}



     }
 };

 mCameraManager.registerTorchCallback(torchCallback, null);//fires onTorchModeChanged upon register
 mCameraManager.unregisterTorchCallback(torchCallback);