How Can I Detect if a Dynamically Loaded Element is Visible After Scrolling?

Detecting Element Visibility after Scrolling

For elements dynamically loaded using AJAX, determining their visibility within the viewport can be crucial. This is particularly relevant for elements that appear after scrolling. Here's an effective method to address this issue:

Using a Custom Function:

The following function checks whether an element is visible within the current viewport:

function isScrolledIntoView(elem) {
    var docViewTop = $(window).scrollTop();
    var docViewBottom = docViewTop + $(window).height();

    var elemTop = $(elem).offset().top;
    var elemBottom = elemTop + $(elem).height();

    return ((elemBottom <= docViewBottom) && (elemTop >= docViewTop));
}

Utilizing a Utility Function:

A more versatile option is to employ a utility function that offers customization:

function Utils() {

}

Utils.prototype = {
    constructor: Utils,
    isElementInView: function (element, fullyInView) {
        var pageTop = $(window).scrollTop();
        var pageBottom = pageTop + $(window).height();
        var elementTop = $(element).offset().top;
        var elementBottom = elementTop + $(element).height();

        if (fullyInView === true) {
            return ((pageTop < elementTop) && (pageBottom > elementBottom));
        } else {
            return ((elementTop <= pageBottom) && (elementBottom >= pageTop));
        }
    }
};

var Utils = new Utils();

Usage:

To determine if an element is visible, simply call this function:

var isElementInView = Utils.isElementInView($('#flyout-left-container'), false);

if (isElementInView) {
    console.log('in view');
} else {
    console.log('out of view');
}

By implementing these methods, you can easily detect the visibility of dynamically loaded elements, enabling optimized page interactions and user experiences.

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