I am playing with the original example of BarCode scanner here:
https://github.com/googlesamples/android-vision/blob/master/visionSamples/barcode-reader/app/src/main
Just optimize your code as following and you have to call this method after building Camera Source class.
private Camera camera = null;
boolean flashmode=false;
private void flashOnButton() {
camera=getCamera(mCameraSource);
if (camera != null) {
try {
Camera.Parameters param = camera.getParameters();
param.setFlashMode(!flashmode?Camera.Parameters.FLASH_MODE_TORCH :Camera.Parameters.FLASH_MODE_OFF);
camera.setParameters(param);
flashmode = !flashmode;
if(flashmode){
showToast("Flash Switched ON");
}
else {
showToast("Flash Switched Off");
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
private static Camera getCamera(@NonNull CameraSource cameraSource) {
Field[] declaredFields = CameraSource.class.getDeclaredFields();
for (Field field : declaredFields) {
if (field.getType() == Camera.class) {
field.setAccessible(true);
try {
Camera camera = (Camera) field.get(cameraSource);
if (camera != null) {
return camera;
}
return null;
} catch (IllegalAccessException e) {
e.printStackTrace();
}
break;
}
}
return null;
}
This will help you to enable flash in Google Vision Api using camerasource object.