Accessing hardware buttons within the camera app

i wish to write a plugin that will enable me to access hardware开发者_如何学C buttons of the phone while using the camera app. how would i go about doing this. or is it even possible.

Sorry, you can't generally do this. There are some keys that applications can respond to while in the background (specifically the media play/pause/etc buttons) but it is not generally possible to process key events while another app has focus.

Your best best is to check the Camera source but you might consider making your own app based on Camera.