Turning on/off flash with Android camera2 API not working
Create these variables:
public static final String CAMERA_FRONT = "1";
public static final String CAMERA_BACK = "0";
private String cameraId = CAMERA_BACK;
private boolean isFlashSupported;
private boolean isTorchOn;
then add these methods:
public void switchFlash() {
try {
if (cameraId.equals(CAMERA_BACK)) {
if (isFlashSupported) {
if (isTorchOn) {
mPreviewBuilder.set(CaptureRequest.FLASH_MODE, CaptureRequest.FLASH_MODE_OFF);
mPreviewSession.setRepeatingRequest(mPreviewBuilder.build(), null, null);
flashButton.setImageResource(R.drawable.ic_flash_off);
isTorchOn = false;
} else {
mPreviewBuilder.set(CaptureRequest.FLASH_MODE, CaptureRequest.FLASH_MODE_TORCH);
mPreviewSession.setRepeatingRequest(mPreviewBuilder.build(), null, null);
flashButton.setImageResource(R.drawable.ic_flash_on);
isTorchOn = true;
}
}
}
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
public void setupFlashButton() {
if (cameraId.equals(CAMERA_BACK) && isFlashSupported) {
flashButton.setVisibility(View.VISIBLE);
if (isTorchOn) {
flashButton.setImageResource(R.drawable.ic_flash_off);
} else {
flashButton.setImageResource(R.drawable.ic_flash_on);
}
} else {
flashButton.setVisibility(View.GONE);
}
}
after this line add this code:
Boolean available = characteristics.get(CameraCharacteristics.FLASH_INFO_AVAILABLE);
isFlashSupported = available == null ? false : available;
setupFlashButton();
at the end call switchFlash() in your desired click listener.
et voilà!
PS. This might be helpful - front/back camera switcher
I see for cameraX, ImageCapture.flashMode only has effect during we build with initial configuration, ImageCapture.Builder() etc. But if you want to enable/disable flash dynamically, you will have to use the following.
camera?.cameraControl?.enableTorch(enableFlash)
If you are wondering what camera is? Captured it from documentation.
// A variable number of use-cases can be passed here -
// camera provides access to CameraControl & CameraInfo
camera = cameraProvider.bindToLifecycle(
this, cameraSelector, preview, imageCapture
)