Develop Reference

textContent returns undefined

I have a table in which I want to extract the text of the active item. I do this with the following code:
var addedWorkout = $("#custDropDownMenuA").find(".dropdown-item.active");
console.log(addedWorkout);
addedWorkout = addedWorkout.textContent;
console.log(addedWorkout);
The problem is that I keep getting undefined. I checked the console and it indeed finds the element I want without fail.
I am relatively new to Javascript, but after over an hour of Googling I could not find the issue and I don't understand why. I know that I can get the text element if I hardcore it using the following line:
document.querySelector("#selectiona1").textContent
but not with:
$("#selectiona1").textContent
What is the difference between these 2? I read that textContent is part of the DOM, to my understanding it relates to objects and according to my console i think it is an object. I made some crazy attempts like putting the object I got into the querySelector, but nothing works.

With this line:
var addedWorkout = $("#custDropDownMenuA").find(".dropdown-item.active");
you're using jQuery to select the .dropdown-item.active inside #custDropDownMenuA, and when you select with jQuery, you get a jQuery object in response. So, addedWorkout is a jQuery object, and jQuery objects generally do not have the same properties/methods as standard HTMLElements. (querySelector is the vanilla Javascript method to retrieve an element)
Either select the [0]th item in the jQuery collection to get to the first matching element:
var addedWorkout = $("#custDropDownMenuA").find(".dropdown-item.active")[0];
Or use the jQuery method to get the text of the first matching element, which is .text():
var addedWorkoutText = addedWorkout.text();
(note the use of a new variable - you will likely find it easier to read and debug code when you create new variables rather than reassigning old ones, when possible)

Your var 'addedWorkout' is a Jquery object, not a html element.
To show the text use:
addedWorkout.text();
Alternatively, you can change the 'addedWorkout' to a html element by adding the index [0], like this:
addedWorkout[0].textContent;

how would i implement something like jquerys .data() in pure javascript?

A project I am working on for works wants a pure JavaScript version of the .data() implementation of jQuery.
I wanted to replicate this.
I did a search and Where is jQuery.data() stored? shows where in jQuery it is stored.
I was hoping that i could just attach a datasegment to an HTML element for accessing later.
Since jQuery is Javascript, I can look there, but it makes use of the jQuery objects, which is what I am trying to abstract. I figured there was some sort of way to associate a hash table like dataset with JavaScript and attach it to an object.

http://jsfiddle.net/npXQx/
shows you can create a .data in the object and then it is preserved. You can access it twice, and the data is there.
This example shows a simple string assignment and a function and it being called multiple times.
var item = document.getElementById("hi");
console.log(item);
item.data = {getType: function(){return this.TYPE},TYPE:"winner"};
var out = item.data.getType();
console.log("out", out);
var two = document.getElementById("hi")
console.log("should say 'winner': ", two.data.getType());

JavaScript to jQuery for KendoUI

I've been using KendoUI and have been using they're command functions. However to call JS I must call named jS functions. No huge deal. When I use the "This" key word it brings back the entire grid and I mus find a value of a child from a sibling of the same parent elements and i wound up doing this ugly thing. The question I have is how can I turn this "thing" into something jqueryable readable and comprehensible
function AddRole(e) {
var $ParentNode = e.target.parentNode.parentNode.children[1].children[0].getAttribute("value", 0);
}

Sorry, but you have other problems.
If you rely on such a structure e.target.parentNode.parentNode.children[1].children[0], your Markup and JS do not scale at all.
Use the oppurtunity to create scalable and consistent code. Or at least, set some id, class or html5 data attribute on the children[0] element in order to identify it properly.

live function with out arguments in jQuery

I wanna select some item by jQuery which has been added after loading page,so I wanna use live() function.I used it before for clicking like following code:
$("selector").live('click')
but now when I wanna use it in another function.
but It will not work with out argument,like it live()
for e.g followin code will alert test (work)
var pos_eq=Math.abs($('.myList').css("left").replace("px","")/$('.myList').children('li').eq(0).css('width').replace("px","")) + 1;
alert("test");
but this will not.
var pos_eq=Math.abs($('.myList').live().css("left").replace("px","")/$('.myList').live().children('li').eq(0).css('width').replace("px","")) + 1;
alert("test");
how can I solve it?

You want a function, not a variable. It looks like you are trying to keep pos_eq up to date after elements have been added to the page. Having a variable auto-update when the DOM changes in the way you are trying to do is not possible with JavaScript. What you can do is use a function instead of a variable. This way whenever the value is accessed you are getting the latest value because it is computed on demand:
function pos_eq() {
var list = $('.myList');
var left = parseInt(list.css("left"));
var width = parseInt(list.children('li').eq(0).css('width'));
return Math.abs(left / width) + 1;
}
I broke your code up into multiple statements to make it more readable. You would use this function the same as you used the variable, but instead add parens to the end to invoke the function:
alert(pos_eq);
alert(pos_eq());

To get a set of objects at the time you need them, just do $("selector"). That will do a query at that time and get the set of objects. There is no need to use .live() in order to query objects on the page. It does not matter whether the objects were part of the original page or were added dynamically later. When you do $("selector"), it will search the contents of the current page and get you the objects that are currently in the page that match the selector.
There is no way to do a live selector query and save it and have it automatically update in jQuery or any other library I know of. The way you solve that issue with a dynamic page is that you just do a new query when you need current results.

The description of live() is: Attach a handler to the event for all elements which match the current selector, now and in the future. It does not give you a live node list despite its name. jQuery does not have any method that returns a live node list(such as those returned by getElementsByTagName etc.) as far as I know.

Using $.data() in jQuery to store flag on element

I am authoring a simple jQuery plugin that turns an input tag into a time-formatted element (on blur it will change 245p into 2:45 pm).
Since I do not want to apply the time format events to the same element twice, I need a way to detect that the specific element in the list provided has not already had the format applied.
This is the relevant part of the code:
var methods = {
init : function(sel) {
var $this = $(sel);
return $this.each(function(){
var data = $(this).data('time_formatted');
if (data) {
return;
} else {
$(this).data('time_formatted', true);
I have heard that using $(sel).data() in a plugin is not a good idea; instead, use $.data(). I don't know why, that's just what I've heard; honestly, I don't know what the difference is.
So my question is, is this the way to accomplish checking if a specific element has had the time formatter applied to it in a plugin?
If you care to see the plugin in it's current development state, see http://jsfiddle.net/userdude/xhXCR/.
Thanks!
Jared

Where have you heard that using .data() is not good? jQuery's plugin autoring page says:
Often times in plugin development, you may need to maintain state or check if your plugin has already been initialized on a given element. Using jQuery's data method is a great way to keep track of variables on a per element basis. However, rather than keeping track of a bunch of separate data calls with different names, it's best to use a single object literal to house all of your variables, and access that object by a single data namespace.
So it should be perfectly fine.