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[This post is by Jean-Michel Trivi, an engineer working on the Android Media framework, whose T-shirt of the day reads “all your media buttons are belong to you”. — Tim Bray]
Many Android devices come with the Music application used to play audio files stored on the device. Some devices ship with a wired headset that features transport control buttons, so users can for instance conveniently pause and restart music playback, directly from the headset.
But a user might use one application for music listening, and another for listening to podcasts, both of which should be controlled by the headset remote control.
If your media playback application creates a media playback service, just like Music, that responds to the media button events, how will the user know where those events are going to? Music, or your new application?
In this article, we’ll see how to handle this properly in Android 2.2. We’ll first see how to set up intents to receive “MEDIA_BUTTON” intents. We’ll then describe how your application can appropriately become the preferred media button responder in Android 2.2. Since this feature relies on a new API, we’ll revisit the use of reflection to prepare your app to take advantage of Android 2.2, without restricting it to API level 8 (Android 2.2).
Source: Android Developers Blog
