Once you have your MediaPlayer set up, I would just set up in your onCreate() and onResume() methods, a check to see if the MediaPlayer is currently playing (MediaPlayer's isPlaying()
method should work for you), and if it is playing, set the button's image and click handler to change it to a pause button. If the MediaPlayer isn't playing, then set it to be a play button.
You'll also need to handle listening for events such as when the MediaPlayer stops (finishes playing the audio file), as well as inverting the button state when you press it (i.e. pressing play changes button to pause, and vice versa).
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…