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Add a link to a form with jQuery (userscript) in Firefox

I'm trying to add a search link to an online form with a userscript using jQuery. I don't work too much in firefox and I feel like things that would normally work in chrome don't in ff 9/10 times for me. But anyway... this needs to be with ff.
I'm taking the text from a <p> element and creating a search url out of it (or trying to). Right now this is the function I'm trying that should be doing it... but it's doing nothing, not even any errors in console
$(function() {
var companyName = $('p')[7]; // Element that contains the name text
var companyText = companyName.text(); // Retrieve the text from element
var mixRankUrl = $("<a></a>").innerHTML("Search Mixrank"); // Create an <a> element
mixRankUrl.href = 'https://mixrank.com/appstore/sdks?search=' + companyText; // Define the href of the a element
var sdkPara = $('label.control-label')[10]; // Where I want it to go
sdkPara.append(mixRankUrl); // Append the element
});
Also, whoever wrote the html uses hardly any ids, and most classes are assigned to 10 or more elements... so unless there's a better way, I'm sort of stuck using node selectors (which stay the same form to form).

The problem is that you try to use jQuery method on DOM element. Don't understand why you don't have any errors with your code.
For exemple : $('p')[7] return a DOM element while $('p').eq(7) return a JQuery object. So you can't use a jQuery method like text() on your DOM element. You need to deal with jQuery object.
For the same reason, you had a problem with the declaration of your label object and with the modification of the href attribute of your link.
Try like this :
$(function() {
var companyName = $('p').eq(7); // Element that contains the name text
var companyText = companyName.text(); // Retrieve the text from element
var sdkPara = $('label.control-label').eq(10); // Where I want it to go
var mixRankUrl = $('<a>',{
text: 'Search Mixrank',
href: 'https://mixrank.com/appstore/sdks?search=' + companyText
}).appendTo(sdkPara); // Append the element
});

How to read text from textfield using jQuery to the variable?

So, I got the page on my local server, and this page contains textarea and button. I am Trying to write onclick function to button, which would read whatever I typed in text area, and make record to database. Just like when I finish typing my question here, and press Ask Question. The problem is that I can't properly read text in text area, it basically sees only what was in there at the moment of loading a page, and just rewrite it. How should I get text, that I typed right before clicking the button? I just want to know how can I copy that text to some var, which I can PUT to database.
$.getJSON('/link/' + tenderId, function (data) {
var description = '';
description += '<textarea id="description" class="form-control" rows="3">' + data.description + '</textarea>';
$('#description').html(description);
});

Use this code inside your click event
var textareaValue = $('textarea#textareaId').val();
html
<textarea id="textareaId"></textarea>
SO answer: https://stackoverflow.com/a/144836/2772017

You need to use val() (I am guessing you are using text()) to get the text of a Text Area:
$('input#mybutton').click(function() {
var text = $('textarea#mytextarea').val();
});
Of course this is just guesswork as you did not supply any code! :)
Update:
The code you added is also incorrect as it adds a duplicate id of description inside a div with an id of description! ID's need to be unique on a page.
Assuming you want a new id here is a cleaner version of your code:
$.getJSON('/link/' + tenderId, function (data) {
var $textArea = $("<textarea>", {class: "form-control", id: "descriptionText", rows: "3"}).val(data.description);
$('#description').empty().append(description);
});

I can't figure out you method logic; it seems you are pulling some json data then appending it to a textarea while in issue description you said that you are trying to save the textarea content so you have to be sending it throug a POST request.
Also does the <textarea id="description"...> element is there in your page or you will be creating it at each button click?
If such is you case, you can try with the following snippet:
$.getJSON('/link/' + tenderId, function (data) {
var $description = $("<textarea>");
$description.attr({
id:'description',
class:'form-control',
rows:'3'})
.html(data.description);
//you will have then to append this jQuery element, e.g: $("#wrapper").append($description)
});

$('button').click(function(){
var myString = $('#description').val();
})
Then use myString whereever you like.

jQuery not recognizing dynamically-inserted DOM element?

Yet another "dynamically change select options based on parent option selected" question.
I have the select values changing dynamically - but after my rails render of the child select - I lose the Chosen styling (the jQuery Chosen plugin) and I cannot operate on this newly injected element.
Here is where the code is right now - it's gone through dozens of iterations -
$('#vendor_block').on('change', '#vendor_name', function(){
overlay.show();
var v = $(this).val();
vndr_json = {};
vndr_json["v"] = v;
$.ajax({
type : "GET",
url : "/purchaseorders/upd_vndr_locs",
data : vndr_json,
success: function(res) {
overlay.hide();
// console.log(typeof(res),res);
jQuery("#vndrAddrOpts").html(res);
}
});
$("#vendor_addresses").chosen(); // WHY DON'T YOU RENDER CHOSEN BOX?!
});
I get this new select box on my page - and I want to fire an event when it changes, but the DOM has already loaded, so it doesn't "see" this element I'm guessing.
Also - the Chosen plugin doesn't render on the element. Not sure why - probably the same reason.
I'm using jQuery's .on() like every post on SO says I should. But it doesn't "reload" the elements inside this parent (and 'vendor_block' is the parent div of 'vendor_name' and 'vendor_addresses').
You can see the difference in the select boxes here:
Any help would be great?
UPDATE:
Adding before and after HTML :
<div id="vndrAddrOpts">
<select class="chzn-select vndrLocs span12" id="vendor_addresses" name="vendor_addresses"><option value="">Select Location</option></select>
</div>
That is the raw HTML - but Chosen does the following when the DOM loads:
<div id="vendor_addresses_chzn" class="chzn-container chzn-container-single chzn-with-drop chzn-container-active" style="width: 100%; margin-bottom: 10px;" title=""><span>Select Location</span><div><b></b></div><div class="chzn-drop"><div class="chzn-search"><input type="text" autocomplete="off"></div><ul class="chzn-results"><li id="vendor_addresses_chzn_o_0" class="active-result result-selected highlighted" style="">Select Location</li></ul></div></div>
This is all fine and well - this is what's supposed to happen.
This is the raw HTML after the select box has been injected:
<div id="vndrAddrOpts">
<select class="chzn-select vndrLocs span12" id="vendor_addresses" name="vendor_addresses"><option value="">Select Location</option></select>
</div>
And here is the rendered box - sans Chosen stuff.
<select class="chzn-select vndrLocs span12" id="vendor_addresses" name="vendor_addresses"><option value="">Select Location</option><option value="532757b4963e6505bc000003">Honolulu</option>
<option value="532768d0963e6505bc000004">Waipahu</option></select>

I found the answer here :
Is there a way to dynamically ajax add elements through jquery chosen plugin?
I actually was approaching this problem in an overly complex way - trying to inject and element instead of just starting with the element and adding options to it.
My AJAX looks like this now:
$.ajax({
type : "GET",
url : "/purchaseorders/upd_vndr_locs",
data : vndr_json,
success: function(res) {
overlay.hide();
var va = $('#vendor_addresses');
// console.log(typeof(res),res);
for (var i=0; i < res.length; i++) {
va.append(
$('<option></option>')
.val(res[i].id)
.html(res[i].name)
);
}
va.trigger("liszt:updated");
// jQuery("#vndrAddrOpts").html(res);
}
});
So instead of even worrying about rebuilding the chosen element from an injected element - we just use the built-in "updated" trigger and it works great.

You are inserting the result of your ajax call into the DOM it's success callback, which is executed whenever it finishes (independent of the script's execution). In this case, your ajax request is being made, the code after it begins executing, and then the callback. The odds of the success callback being called before the next line of code are slim, as the ajax call is an http request which takes much longer than a line of JavaScript executing.
You want to put the code in the success call back, such as:
$.ajax({
type : "GET",
url : "/purchaseorders/upd_vndr_locs",
data : vndr_json,
success: function(res) {
overlay.hide();
$("#vndrAddrOpts").html(res);
$("#vendor_addresses").chosen();
}
});

I think the chosen method is firing before the element has actually been rendered on the page, and jQuery can't find it. Try putting $("#vendor_addresses").chosen(); as part of the AJAX success callback. Failing that, try commenting out the chosen() method, running the AJAX script, then manually running the chosen() method. If it works that way, you have to delay it a little bit.
EDIT:
Actually, looking more closely at your code, it appears you're using an ID tag instead of a class. Do multiple HTML elements have the #vendor_address id? If so, use a class instead, and use $('.vendor_addresses').last().chosen();. If you use an ID, and use an ID selector, jQuery will pick the first element if finds with that ID, and stop there.
Lesson to be learned? Use an ID for UNIQUE elements, and classes for multiple elements of the same 'class'.

Add items to drop-down box

I can't seem to find the correct syntax to get this working:
$.get('/templates/mytemplate.html', function (template) {
$(template).find('select').append($("<option />").val(0).text('Please select ...'));
$.each(dashboard.myArray, function () {
$(template).find('select').append($("<option />").val(this.Id).text(this.Text));
});
$('#new-items').append(template);
});
The template variable is just a string of html like:
"<form class="user-item">
<select class=".sc" name="context" />
<input type="hidden" name="id"/>
<input type="hidden" name="date"/>
<form>"
I've tried selecting the select item on name 'select[name=context]' and using a class selector like '.sc' as well ... none seem to work but I've got similar code working fine elsewhere. Very confused.

The problem is template is a string. in your case you are creating a new jQuery wrapper for that element every time and manipulating it but that does not actually change the contents of the string in template, it just changes another in memory object
You need to create a reference to a new jQuery wrapper for template then do the dom manipulation using that reference and at the end append it to the container element
$.get('/templates/mytemplate.html', function (template) {
var $template = $(template);
$template.find('select').append($("<option />").val(0).text('Please select ...'));
$.each(dashboard.myArray, function () {
$template.find('select').append($("<option />").val(this.Id).text(this.Text));
});
$('#new-items').append($template);
});
Demo: Problem, Solution

such code will work
var value = 'some_value',
text = 'some_text';
$('#id').append($('<option value='+value+'>'+text+'</option>'));

the reason your code it's not working is you are modifying a variable but don't assign the changes to variable
$(template).find('select').append($("<option />").val(0).text('Please select ...'));
this line never stores changes to template, it should be :
template = $(template).find('select').append($("<option />").val(0).text('Please select ...'));

How to make a list in a web page that can be edited without reloading

Here's some low-hanging fruit for those more comfortable with Javascript than I...
I want to improve a Moodle plugin's admin UI. (Moodle is a PHP-based web app). What I need to do is take what is currently a text box, with semi-colon delimited entries and replace that with a editable list.
The HTML elements I would use is a select list, a text input field and another hidden textfield. I guess a couple of submit buttons too, one for adding, and the other for removing of entries.
The behaviour would be:
Entries can be added to the select list from the visible textbox upon some kind of submit (this cannot reload the page).
The hidden textbox would contain all the entries from the select list, just semi-colon delimited
There's a function to remove entries from the select list that also does not reload the page.
The hidden textbox is updated with add/remove actions
This seems to me like something that's easy enough. Though I'm having a hard time finding a close enough example to rip off.
This sample code is as close as I've found thus far. There's got to be some good examples of precisely this sort of thing out there. Any decent pointers will be rewarded with + votes.

What you want to do is use JavaScript and manipulate with the DOM of the webpage. Basically, the HTML of a webpage is parsed and rendered by the browser into a tree of elements. Each HTML tag like <select> is an element in the tree. You use JavaScript to interact with this tree by performing operations like removing elements from this tree or adding elements to this tree. (Note that preforming operations on the tree will not refresh the page.)
The standardized API to do these sorts of manipulation in JavaScript is known as the DOM. However, many people, myself included, think that this API is very clunky and not nearly expressive enough. Doing even trivial things require tons of lines of code. For this reason, many developers do not use the DOM directly instead using more powerful libraries, such as jQuery, to make their lives easier.
Below is an example of some HTML + JavaScript that I think mimics most of your requirements. Ideally for learning purposes, this would be written purely using the standard W3C DOM API, but since your problem is not that trivial, I resorted to using jQuery instead.
The HTML:
<select id="list" multiple="multiple"></select>
<input id="removeButton" type="button" value="Remove"></input>
<div>
<input id="optionAdder" type="text"></input>
<input id="addButton" type="button" value="Add"></input>
</div>
<br>
<input id="clearButton" type="button" value="Clear All"></input>
<div>Not So Hidden: <input id="hidden" type="text"></input></div>
The JavaScript:
// Uses jQuery to define an on document ready call back function
$(function(){
// The code in this function runs when the page is loaded
var options = []; // contains all the options
// add new option to drop-down
var addOption = function(optText) {
// Create new option element and add it to the <select> tag
$('<option></option>')
.attr('value', optText).text(optText)
.appendTo( $('#list') );
};
// writes the names of all the options in the "hidden" text box
var fillHidden = function() {
$('#hidden').val('');
var hiddenText = "";
for(var i=0; i< options.length; i++) {
if(hiddenText) {
hiddenText += "; ";
}
hiddenText += options[i];
}
$('#hidden').val(hiddenText);
}
// Bind the click event of the "Add" button to add an option on click
$('#addButton')
.click(function(){
var optText = $('#optionAdder').val();
if(optText) {
addOption(optText);
}
$('#optionAdder').val('');
options.push(optText);
fillHidden();
});
// Bind the click event of the "Remove" button to remove the selected options on click
$('#removeButton')
.click(function(){
$('#list option:selected').each(function(){
var optIndex = $.inArray($(this).val(), options);
if(optIndex > -1) {
options.splice(optIndex, 1);
$(this).remove();
}
fillHidden();
});
});
// Bind the click event of the "Clear" button to clear all options on click
$('#clearButton')
.click(function(){
$('#list').children().remove();
options = [];
fillHidden();
});
});
Here is a jsfiddle demonstrating the code