Question

I'm using a jquery script called magnific popup and I'm trying to access a variable I created in a callback function, inside another callback function but I can't work out how to do it. My code for the magnific init looks like this:

$('.packery').magnificPopup({
    delegate: '.js-modal',
    type: 'ajax',
    mainClass: 'mfp-zoom-in',
    removalDelay: 500, //delay removal by X to allow out-animation
    callbacks: {
        elementParse: function(item) {
            item.community = item.el.attr('data-community');
            var communityClass = item.community;
            console.log(item.community);
            // this ^ does actually print the data-community 
            console.log('Parsing content. Item object that is being parsed:', item);
        },
        resize: function() {
            console.log('Popup resized');
            // resize event triggers only when height is changed or layout forced

            $('.mfp-bg').addClass(communityClass);
        }
    }
});

If I try and set $('.mfp-bg').addClass(communityClass); or $('.mfp-bg').addClass(item.community); I get a Uncaught ReferenceError: communityClass is not defined.

I can't apply a class to mfp-bg inside elementParse as that element hasn't been created yet.

I know that I can't use variables from different functions in javascript, but I'm a bit stuck at this point on how I can actually use the data-community attribute inside the resize callback, because it seems like I can only create the variable inside the elementParse callback?

Any help would be much appreciated, cheers.

Answer 1

您可以在函数外部创建一个全局变量，并为其指定item.community。这样你就可以在其他回调中访问它了

例如：

var communityClass;
$('.packery').magnificPopup({
delegate: '.js-modal',
type: 'ajax',
mainClass: 'mfp-zoom-in',
removalDelay: 500, //delay removal by X to allow out-animation
callbacks: {
    elementParse: function(item) {
        item.community = item.el.attr('data-community');
        communityClass = item.community;
        console.log(item.community);
        // this ^ does actually print the data-community 
        console.log('Parsing content. Item object that is being parsed:', item);
    },
    resize: function() {
        console.log('Popup resized');
        // resize event triggers only when height is changed or layout forced

        $('.mfp-bg').addClass(communityClass);
    }
}
});

Answer 2

我在console.logging之后意识到已经有了一个我可以访问的currItem位，所以我把代码更改为了这个并且现在工作正常。

$('.packery').magnificPopup({
    delegate: '.js-modal',
    type: 'ajax',
    mainClass: 'mfp-zoom-in',
    removalDelay: 500, //delay removal by X to allow out-animation
    callbacks: {
        elementParse: function(item) {
            item.community = item.el.attr('data-community');
        },
        resize: function() {
            $('.mfp-bg').addClass(this.currItem.community);
        }
    }
});

Accessing js variable inside a separate callback (function)

2 个答案: