Develop Reference

Cannot get value of textarea with Shopify Product Options by Bold

I'm trying to get the value of a textarea with Shopify Product Options by Bold and it is currently not working. I am able to get the value of a textarea locally, but I can not get the value when I move the code over to Shopify. I have looked here and here to no avail.
Here's the relevant code:
document.getElementById("248832").onkeyup=function(){getVal()};
var textbox = document.getElementsByName("properties[Message Body]")[0].value;
and here's the textarea I'm trying to get the value of
<textarea data-option-key="ta_248832" id="248832" class="bold_option_child shapp_full_width " name="properties[Message Body]"></textarea>
When I try to run this on Shopify, I get an error saying "Uncaught TypeError: Cannot set property 'onkeyup' of null", although I did notice that at one point shopify runs the following jQuery code, which might be what's causing my problem:
<script>
jQuery('#248832').change(function (){conditional_rules(7437760391);})
</script>
I am trying to get the value of the textarea so I can run get the amount of words in said textarea.
Any help would be greatly appreciated!

Look to see if the element that is returned as null has loaded yet. Others in similar situations fixed this by loading the script last. Hope this is helpful :)
https://stackoverflow.com/a/25018299/1305878
https://stackoverflow.com/a/31333349/1305878
https://stackoverflow.com/a/23544789/1305878

Solution
You are trying to use something similar to jQuery methods without jQuery:
document.getElementById("248832").onkeyup=function(){getVal()};
while DOM elements don't have the onkeyup method. It should be
jQuery("#248832").on("keyup",function(){getVal()});
Extra notes
even without using the recommended '.on' method, you have to write it as
jQuery("#248832").keyup(function(){getVal()});
(docs), not as
jQuery("#248832").onkeyup(function(){getVal()});
If you'd like to use DOM methods, that would be
document.getElementById("248832").addEventListener("keyup",function(){getVal()});
Also, may be you have wrote this as a minimal example, but the fact that you only call getVal() and don't pass the value somewhere sounds strange, although I don't know if what getVal() does exactly.

Problem with jQuery - error when trying to find 2 tags

I have the following DOM structure:
/*:DOC += <div id='testDiv' class='testDivClass'><div id='innerTestDiv'></div></div><span id='testSpan' class='testSpanClass'><span id='innerTestSpan'></span></span>
Now I tried to run jQuery select against them as follow. The first one returned alright, but the second one failed:
// works
var result = $('#testDiv')[0];
alert(result.id);
// failed: id is null or not an object
var result2 = $('#testSpan')[0];
alert(result2.id);
I tried selecting id instead of class and got the same results.
My question is: how can I get the second select to work? Is there some sort of invisible iterator/pointer in jQuery which I need to reset to the beginning of the DOM before the second select?
Thanks.
EDIT: Ok this is the official "does not work" version. testDiv matched, but testSpan did not, hence I got an error saying id is null or not an object error in the second alert.
UPDATE: I did a test by swapping testDiv and testSpan in the html. Now BOTH select failed.
UPDATE2: I have changed the html back to what it used to look like. I'm using JsTestDriver to write up the test, but it is actually not calling anything at the moment. The actual html looks messier than this (more nested tags). I'm trying to get this simplified version to work first. It appears that jQuery was able to get into the first select, whether it'll be span or div, but couldnt get out of it to do the second select. I've replaced jQuery.js and jsTestDriver.jar to no avail.
Thanks.

The .className selector matches by class, not ID.
Therefore, $(span.testSpan) won't match any elements.
You need to change it to $('span.testSpanClass') ot $(span#testSpan') (using the #id selector, which matches ID).
For more information, read the documentation.

I don't know why, but for me your code worked well.
I added $(document).ready(function() { before that code, and when I opened the test page, the alert box showed up perfectly, both of them! I don't know when do you want this alert box showed, but if it is when visitor open the page, just add that code. Otherwise, add
function objectid() {
var result = $('#testDiv')[0];
alert(result.id);
var result2 = $('#testSpan')[0];
alert(result2.id);
}
That code worked well for me, too.
PS: Sorry if you don't understand my bad english.

More than likely, there is something else wrong with the HTML you're actually using. Since you're posting only a tiny bit of the html, we can't actually test your problem. Post the entire page, or at least the smallest piece of it that actually has the problem when you run your test.

I tested the jQuery code you reported on JS Bin, and the code worked fine. As the code is very basic, I don't think the problem is caused by the version of jQuery used.

What I ended up doing is wrapping the entire html with a div or span tag. I found that jQuery could not get out of a div/span tag once it gets into one (in my above example), so I just make it to go into a div/span tag once.
Not sure whether this is a patch or ugly fix, but it solved my problem for now.
Thanks for all the help!

Use "#" to select by id, use "." to select by class...

Javascript getElementById - reading works, altering doesn't

So, I have this pretty complex ajax thing going.
It loads new html (including div tags and all) to show up on the page.
I included a 'more' link to load additional data.
This more link links to my javascript function. The 'more' link is located in a div, which I gave a unique id. The next time the load function is called, I use document.getElementById(the id).style.display="none"; to "remove" this div from the look of the page.
I set error traps for this, the div with that id is found without problems, but javascript fails to change my style property.
I tested alert(document.getElementById(the id).innerHTML); and that worked without problems - hence the title of the question.
So, does anyone have any ideas/do I need to offer more information? The main problem is that it doesn't throw any errors anywhere, yet it fails to complete the task I asked...
Here's a bit of code to go with it -
try
{
var myidthing = "morelink" + ContentStart.toString(); //the id is correct
var div = document.getElementById(myidthing);
if (!div)
{
}
else
{
div.style.display="none"; //this doesn't work, but doesn't raise an error
alert(div.innerHTML); //this works without problem
}
}
catch(theerr)
{
alert(theerr);
}
------------------------->EDIT<-------------------------
I'm incredibly sorry if I upset any people.
I'm also angry at myself, for it was a stupid thing in my code. Basically, I had a variable that stored the contents of a parent div. Then I (succesfully) removed the div using the removeChild() method. Then my code pasted the contents of that vaiable (including the div I wanted gone) back into the parent div.
I switched around the order and it works fine now.
Again, excuse me for this.

Throwing out a few ideas of things to look for:
You said the div is generated by javascript. Is it possible the div you are targeting is not the one you think you are? It could be you are targeting another div, which is already hidden, or obstructed... or maybe the innerHTML you are displaying goes with a different element than the one you intend to target. Put an alert or script breakpoint in the if(!div) case, also, and see if it's going down that path.
If the above code is only a stripped-down version of your actual code, check your actual code for typos (for example: style.display = "none;";)
Using the FireBug plugin for FireFox, inspect the target element after the operation completes, and make sure that the display: none appears in the style information. If not, use FireBug's debugger to walk through your javascript, and see if you can figure out why.
Use FireBug to break on all script errors, in case there is another error causing this behavior.

Try empty quotes instead of 'none' and see if that works?:
document.getElementById('element_id').style.display="";
Failing that, don't change the style, just add a class which hides the element.

Frustrating issue with JavaScript's getElementById()

This is the gallery I've been asked to implement
http://sandbox.leigeber.com/slideshow/
I've chopped and changed it ever so slightly so it'd fit into the new site's templating system a bit easier.
Whenever I run it, this line causes an error
ta=document.getElementById(thumbid);
Saying that ta is null. I know the thumbid var's value does exist as an Id of the unordered list.
I've tried to figure what's been going on for at least half an hour now, and can't seem to nail it!
Can someone please tell me what I'm doing wrong?

Yeah the code looks fine, and running the same lines from Firebug console work OK, so it makes me wonder if the thumbs element actually exists at the time of running? Is it in a document.ready-style handler? If it's being called before the element exists on that page, then ta will be null, which would create that error.

It looks like the slideshow function is called for initialization too early. This will be called before the DOM tree is ready:
var slideshow = function() {
...
} ();
try removing that () at the end.

Good news! jQuery is written in vanilla Javascript! You should be able to copy out their method for getting elements by ID and use that.

It's a little unclear what value thumbid should have, but it looks to me like your problem is that the li items in your unordered list don't have ids, they have values.
Calling document.getElementById('thumbs') works fine to get the ul element of the list itself.

In Safari 4 line 19 was throwing me a type error regarding ta which was null.
This is due to the line you pointed out where ta was assigned.
I like how you encapsulate the functions in a closure, but I think the window.onload can be changed to be more jQuery like; the same can be said of actually selecting the elements you're looking for, something like t=$('ul#thumbs li') should do the trick. I don't know if throwing a var in front of ta is going to fix anything, but it's worth a shot.

prefilling dynamically created textbox with javascript in IE

I'm trying to dynamically add some textboxes (input type=text) to a page in javascript and prefill them. The textboxes are coming up, but they are coming up empty. What is the proper way to pre-fill a textbox. Ideally I'd love to use the trick of creating a child div, setting the innerhtml property, and then adding that div to the parent main div but that didn't work. Then I thought I'd use the dom but setting textboxname.value before or after insertion won't work and doing txttextbox.setattribute('value','somevalue') won't work either. Works fine in firefox. What gives? This has to be possible? Here is my code. I know I'm only using string literals, but these will be replaced with the results of a web service call eventually. Below is some code. Oh and how do you format code to show up as you type it? I thought it said to indent four spaces, and I did that but the code is still on one line. Sorry about that.
var table=document.createElement('table');
var tbody=document.createElement('tbody');
var row=document.createElement('tr');
row.appendChild(document.createElement('td').appendChild(document.createTextNode('E-mail')));
var txtEmail=document.createElement('input');
row.appendChild(document.createElement('td').appendChild(txtEmail));
tbody.appendChild(row);
table.appendChild(tbody);
//document.getElementById('additionalEmails').innerHTML="";
document.getElementById('additionalEmails').appendChild(table);

txtEmail.value = 'my text'
Does not work?

You can also use Prototype to do this easily:
document.body.insert(new Element("input", { type: "text", size:20, value:'hello world' }))

I've encountered problems similar to this in the past, and while my memory is a bit fuzzy on why it was happening exactly, I think you may need to make sure the element is actually added to the DOM before modifying its value. e.g:
var txtEmail=document.createElement('input');
document.getElementById('someElementThatAlreadyExists').appendChild(txtEmail);
txtEmail.value = 'sample text';

I ended up solving this problem by injecting the html directly into a page via a child div. That did work, it's just that I am blind and the software I use to read the screen for some stupid reason failed to see the text in the textbox. Go figure. Thanks for the tip on prototype though, if I ever decide not to cheat and add the eleements to the dom directly, I'll do it that way.