What is prevObject and why is my selector returning that?

javascript jquery offset
shuji picture shuji · Oct 31, 2013 · Viewed 29.7k times · Source

I'm trying to obtain the top from an element but I'm getting this error, what does it mean and how do I get rid of it?

$(".hover").offset().top

>Uncaught TypeError: Cannot read property 'top' of undefined

$(".hover")

[div.hover, prevObject: x.fn.x.init[1], context: document, selector: ".hover", jquery: "2.0.3", constructor: function…]
[prevObject: x.fn.x.init[1], context: document, selector: ".hover", jquery: "2.0.3", constructor: function…]

This happens inside the drop event of jqueryui when I try to drop it into a nested droppable.

$.fn.makeDroppable = function(){
    $(this).droppable({
        drop: function(event, ui) {
            console.log($(".hover"));
            console.log($(".hover").offset().top);
            $(".hover").makeDroppable().removeClass("hover");
        },
        over: function(event, ui) {
            $("<div>").addClass("hover").appendTo(this);
        }
    });
}
$(".container").makeDroppable();

<div class="container"></div>

Answer

Ami picture Ami · Apr 29, 2014

jQuery returns prevObject if the DOM does not have the element for which jQuery is being run. You might see the element in your source at the run-time however, it is not not bound to the DOM and therefore, it shows prevObject. Try checking your js file again or else paste the code here.

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