Calling signals based on evaluation

[MrOrphanage]

Hi all,

I've just found out about signals but I'm having some difficulty implementing them. I came across them while searching for a solution to a problem I'm having: namely I'm trying to call a function when two variables decrement down to 0. So, when "pTurnsLeft == 0 && cTurnsLeft == 0" then the function should call once. I initially threw this check in to the update statement, and it worked for a bit. However, I'm now having the issue that the function is constantly called. This wasn't any issue at first for me, because after the function ran, I reset the entire play state to start the game over. However, I'm trying to change the handling of how to reset the game so that instead of re-calling the play state completely (and losing all the variable changes that were made in the round) I just manually reset the variables I want to so the game "starts over" manually. The issue at hand now though is since my update function is evaluating the above expression, it's calling my function 60 times/second and I'm not able to reset my game loop properly. This is where signals come in.

I've been led to believe that I can create a signal that evaluates the above expression and calls my function just once. This is obviously appealing as it would fix my issue, but I'm having trouble figuring out exactly where I need to tell the signal what expression to evaluate before it dispatches. Am I misunderstanding how signals work here or can I in fact use a signal in my play state to fire off a function when the expression I mentioned above is true?

Here's what I have so far:

var roundEnd = new Phaser.Signal();
roundEnd.add(this.callResults, this);

/* I'm not sure how but I need to do this:
roundEnd.dispatch() when "this.pTurnsLeft == 0 && this.cTurnsLeft == 0"*/

EDIT: For what it's worth, I've read through a couple of signals tutorials I found from googling but all seem to focus on dispatching things based on touch/mouse click events or key presses. I understand how to implement those, but I'm confused about how to go about implementing listeners for expression evaluation.

[samme]

The Signal itself doesn't do any evaluation, it just hooks up listeners and waits for you to trigger it.

You can use addOnce:

// @create:
var roundEnd = new Phaser.Signal();
roundEnd.addOnce(this.callResults, this);

// @update:
if (this.pTurnsLeft == 0 && this.cTurnsLeft == 0) {
  roundEnd.dispatch();
  return;
}

 

[MrOrphanage]

Ah, I see. I mistakenly thought that you could somehow tell the signal itself to evaluate. This solution should work great though, thanks so much!