How to customize hello message for media app in android auto?

I'm currently developing one Android auto media app. How can I do the same as Spotify when users not login, to give a message "Please login to use spotify". I'm not gonna do a login judgement, I just want to change the default hello message shown on the dashboard. By default, the media app always show "To play something, open the menu...." How can I change it? Help!

Solution

You can use the setErrorMessage() in the PlaybackStateCompat class to accomplish this. When the PlaybackStateCompat is assigned to a Media Session, its used to describe the current operational state of the player.

private void playbackStateErrorMessage(int code, String message) {
    PlaybackStateCompat.Builder playbackStateBuilder = new PlaybackStateCompat.Builder();
    playbackStateBuilder.setState(PlaybackStateCompat.STATE_ERROR, -1L, 1.0F);
    playbackStateBuilder.setErrorMessage(code, message);
    mSession.setPlaybackState(playbackStateBuilder.build());
}