When switching back to the fragment, an error occurs, how to fix it?

Question

Java

Hello, I have a stop button, when I click on play, then I click on stop, the radio broadcasting stops, but there is such a moment, once I accidentally clicked on stop 2 times and the application crashed, how can I handle the event so that when I click 2 nothing did not happen, below is the stop button listener code and the screen

@Override
            public void onClick(View view) {
                if (mediaPlayer.isPlaying()) {
                    mediaPlayer.stop();
                    mediaPlayer = null;
                    playPause.setChecked(false);
                }
                else {
                    playPause.setChecked(true);
                }
            }

Thank you very much in advance!

Answer 1

Correct the check:
if (mediaPlayer != null && mediaPlayer.isPlaying()) {
...