Manage Flashlight on the SSaurel's Blog

ManageFlashlight.java

imageFlashlight.setOnClickListener(new View.OnClickListener() {
  @Override
  public void onClick(View view) {
    if (hasCameraFlash) {
      if (flashLightStatus)
        flashLightOff();
      else
        flashLightOn();
    } else {
      Toast.makeText(MainActivity.this, "No flash available on your device", 
            Toast.LENGTH_SHORT).show();
    }
  }
});