Properly shutting down upon state change?

[Mike018]

I'm just now starting to clear variables, tweens, and sprites on state change and have some questions since I never see this stuff in phaser tuts.

• Is the code below properly stopping, removing and clearing variables of the text, audio, sprites, and tweens?
• If a tween does not have an onComplete in the code, do I have to do .onComplete.removeAll during the shutdown or is stopping and setting the variable to null sufficient? 
• When a sprite has its input enabled and events attached to it, do I have to manually clear that or is it removed once the sprite is killed? What about when it's destroyed?
• Is there a nicer way to clear everything instead of having so many if statements as well as having to make every variable reachable outside the method scope, maybe putting every sprite in a group and doing a forEach to remove it?

If you have an example of your shutdown methods, I'd like to see it!

shutdown() {

    //DESTROY BITMAP TEXT
    this.text = null;

    //DESTROY AUDIO
    if (this.audio) {
      this.audio.stop();
      this.audio = null;
    }

    //KILL SPRITES
    if (this.startButton) {
      this.startButton.kill();
      this.startButton = null;
    }

    //DESTROY TWEENS
    if (this.tween) {
      this.tween.onComplete.removeAll();
      this.tween.stop();
      this.tween = null;
    }

  }

 

[drhayes]

To the codes! https://github.com/photonstorm/phaser/blob/master/src/core/StateManager.js#L384

That's everything Phaser does for you when shutting down a state. All the tweens are killed, for instance. Depending on how you transition to a new state the world is also cleared, which means you *probably* don't need to kill individual sprites. At least, I never do.

Failing that, if "this.startButton" has a chance of being null in shutdown then, no, you must conditionally destroy it. You could shorten that to "this.startButton && this.startButton.destroy();" if you're going for a brevity thing.