AS3：一个键具有多个选项，可防止多次按下

Question

I have a "pause function" in my AS3 code, the problem is that i can't figure the logic necessary to give the letter "P" the capacity to pause and unpause and at the same time limit the number of presses to one at a time. My code so far (working ,yes, but without the "one press at a time" limit).

    public function PauseDown(event:KeyboardEvent):void
    {
        if (event.keyCode == Keyboard.P)
        {
            pause = true;
            trace ("apreté pausa");
            pausa();
        }
    }
    public function pausa():void 
    {
        trace ("pausa");
        if (pause == true && paused == false)
        {
            paused = true;
            backgroundLvL1.removeEventListener(Event.ENTER_FRAME,update);
        }
        else if(pause == true && paused == true)
        {
            paused = false;
            backgroundLvL1.addEventListener(Event.ENTER_FRAME,update);
        }
    }

Answer 1

Your 'PauseDown' function should probably be called something else, because it's going to be called whenever ANY key is pressed; Something like 'keyPressed' is probably more descriptive.

If you want to have only ONE key acknowledged as the most recently pressed key, I would set a variable (eg _currentKeyCode) to the event.keyCode in the 'keyPressed' function. Then, in your game loop function you can check the value of _currentKeyCode and have the game respond accordingly.

In the 'keyPressed' function you could also still include your test to see if 'P' has been pressed.
Note that you should also have a 'keyReleased' function, triggered on a KeyBoardEvent.KEY_UP event. This could check if _currentKeyCode == the event.keyCode and, if so, set _currentKeyCode to -1. Then, in your game loop, -1 would signify no key presses.

One last, slightly irrelevant, thing: In the 'pausa' function you don't need to check if 'pause == true' because the pausa function is only called when pause == true.