How to turn on FlashLight in Lollipop programmatically Android

Question

Camera cam = Camera.open();     
Parameters p = cam.getParameters();
p.setFlashMode(Parameters.FLASH_MODE_TORCH);
cam.setParameters(p);
cam.startPreview();

Answer 1

Your code should actually work. Please check if you added the permission for using the camera properly:

This should be added to your AndroidManifest above of your other specifications.

Additionally, there is an interesting discussion about different devices and an example which should work on every device here: Flashlight in Android

If you dont want to use the deprecated API, you can check out:

Package Summary of Camera2

Camera device specification on the new api

Unfortunately I can not give you an example for using the new API, because I did not use it myself yet.