在后台启动和停止音乐

Question

I'm making a game and there is background music in it. I want to add a mute button that starts and stops the music but I don't know how to. The method that creates the music is:

public static void backgroundMusic() {
    try {
      AudioInputStream audio = AudioSystem.getAudioInputStream(new File("SoundFile.wav"));
      Clip clip = AudioSystem.getClip();
      clip.open(audio);
      clip.start();
    } 
    catch(UnsupportedAudioFileException uae) {
      System.out.println(uae);
    } 
    catch(IOException ioe) { 
      System.out.println(ioe);
    } 
    catch(LineUnavailableException lua) { 
      System.out.println(lua);
    }
}

What I want to do is in my action handler for the button, I want to add a mute button that starts and stops the audio if the user pleases. So it would be like: if(e.getSource() == muteButton) { //Starts and stops music }

How would I go about doing this? Thanks for your help!

Answer 1

It has nothing to do with sound, it has to do with being able to access the Clip reference. Because you've created local reference to Clip , nothing else will be able to access the reference in order to change the state...

You need to change the local reference so that it is a class level reference, allowing other methods to interact with it...

For example...

protected static Clip clip;


public static void backgroundMusic() {
    try {
      if (clip == null) {
          AudioInputStream audio = AudioSystem.getAudioInputStream(new File("SoundFile.wav"));
          clip = AudioSystem.getClip();
          clip.open(audio);
      } 
      if (!clip.isRunning()) {
          clip.start();
      }
    } 
    catch(UnsupportedAudioFileException uae) {
      System.out.println(uae);
    } 
    catch(IOException ioe) { 
      System.out.println(ioe);
    } 
    catch(LineUnavailableException lua) { 
      System.out.println(lua);
    }
}

public static void stopBackgroundMusic() {
    if (clip != null) {
      clip.stop();
    } 
}

ps- I've never really dealt with the audio APIs so there might be a few other tweaks you need to make, but this is the basic concept you are after...