What's the Android OS model for handling custom hardware keys?

Let's say i have an android device that has some extra buttons on it, can i registe开发者_如何学Gor one of those buttons to launch my app? is there a configuration file on the device that controls hardware keys behavior?

Let's say i have an android device that has some extra buttons on it, can i register one of those buttons to launch my app?

You would have to ask the device manufacturer that question. Non-standard buttons, by definition, are non-standard, so the device manufacturer would need to document their use. In particular, you would need to know if there is a broadcast Intent sent out if the button is pushed and is not used by the current activity, as is the case for the camera and media buttons today.