key event in Android
<p>The currently key  events listener provided by android "onKeyUp", "onKeyDown" are associated to an activity , so they are notified of the key events if the activity's views are focused . What I want is to be able to increase/decrease the volume by pressing some of the device's key , without  writing a listener in every activity , especially as my application has a lot of activities . Is there a way to write a "listener/piece of code" for key events that will be called always during the life of an application when a key is pressed, no matter what the user is doing at that time ?</p>
