Making sure a javascript function is not called, if called already - Stack Overflow

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I am using google maps for a project. I need to be able to hide and display multiple maps. I cannot use a basic toggleDiv type function alone. This is because Google maps will ignore the intended size of the div when the div is set to display: none from CSS. (for whatever reason it is fine with being toggled by javascript.) I could use GSize(width, height) but it cannot handle percentages. Since I need the map to be 100%, 100%, this is not an option. I figured out a way around it which is to call the second map's function using onClick, rather then loading all the functions using body onLoad. But, then the zoom of the map is not saved and the map is just reloaded.

So, I need to check if a function has been called, and if so, do not recall it. I cannot figure out how to do this. Any help is appreciated.

Thank you.

I am using google maps for a project. I need to be able to hide and display multiple maps. I cannot use a basic toggleDiv type function alone. This is because Google maps will ignore the intended size of the div when the div is set to display: none from CSS. (for whatever reason it is fine with being toggled by javascript.) I could use GSize(width, height) but it cannot handle percentages. Since I need the map to be 100%, 100%, this is not an option. I figured out a way around it which is to call the second map's function using onClick, rather then loading all the functions using body onLoad. But, then the zoom of the map is not saved and the map is just reloaded.

So, I need to check if a function has been called, and if so, do not recall it. I cannot figure out how to do this. Any help is appreciated.

Thank you.

• javascript

Share Improve this question Follow asked Jul 6, 2011 at 20:10 Mitchell IngramMitchell Ingram 2111 silver badge33 bronze badges 2

• Do you have control over the code of this function? – donut Commented Jul 6, 2011 at 20:16
• For a prettier solution - see teresko's answer. Tracking variables are kept INTERNAL to the function and don't clutter the outer scope. – John Strickler Commented Jul 6, 2011 at 20:33

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4 Answers 4

Sorted by: Reset to default 7

Another "lazy" variant:

var doOnce = function () {
    // do something

    doOnce = function () {}
}

---

As for the original problem, if the function you want to run once is the click event handler, you'd better remove the click event listener.

Define a variable as such. var beenFired = false;

in the function do this:

function myFunction()
{
    if(!beenFired)
    {
        //TODO FUNCTION
        beenFired = true;
    } 
}

That will check to see if hasn't been fired yet and if not fire it. You could even do it around the function call itself.

if(!beenFired)
    myFunction()

function myFunction()
{
    //TODO FUNCTION
    beenFired = true;
}

var func = (function(){
    var first = true;
    return function( a, b, c){
        if ( !first ){
            return;
        }
        first = false;

        console.log( arguments );
    }
})();

func( 1, 2, 3); // in console : [ 1, 2, 3]
func( 1, 1, 1); // nothing happens;

If I understand:

var isCalled = false;

function f() {
  if (!isCalled) {
    isCalled = true;
    // ...
  }
}

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