jquery - reload function, lose variable value - javascript

lets say i have this function:
$("#click").click(function myFunction(){
var id = $(this).attr("id");
myFunction();
});
Now, obviously, after the click event, id == "click", but when the function reloads, id == undefined.
Is there a way that i can reload the function without redefining the variable?

You're recursively calling a closure function. Here's a working copy where you can use a callback function to access the variable:
$("#click").click(function() {
var id = $(this).attr("id");
console.log("click id: " + id);
myFunction(id);
});
function myFunction(id) {
console.log("id: " + id);
}
JSFiddle Example

You seem to be calling a closure function recursively. In the context where the closure function myFunction is a callback to the click event handler, $(this) resolves to the element on which the click was performed and so you will be able to get the id attribute within the function. However, when you call it again, $(this) doesn't resolve to the same element which is why your id will be undefined.

Related

Conditional addClass not working for each elements with same class

Les say I have some buttons with same class. On page load I am checking some value using ajax for each button. Depending on returned value of ajax request I want to add some class to the buttons, but it is not working,
$(document).ready(function(){
$('.add-remove-permissoion').each(function(){
var child = $(this).val();
var parent = $('#parent-name').text();
$.get('my-url', function(data){
if(data == 1){
$(this).addClass('glyphicon glyphicon-ok');
}else{
$(this).addClass('emptybox-blank');
}
});
});
});
I have checked that my ajax request is returning correct data. What is that I am doing wrong here?
The problem is the this reference inside the ajax callback, in the success callback this refers to the jqXHR object not the dom element reference that is why it is not working.
You can use a closure variable as given below to fix the problem
$(document).ready(function () {
$('.add-remove-permissoion').each(function () {
var $this = $(this),
child = $this.val();
var parent = $('#parent-name').text();
$.get('my-url', {}, function (data) {
if (data == 1) {
$this.addClass('glyphicon glyphicon-ok');
} else {
$this.addClass('emptybox-blank');
}
});
});
});
this in the context of the $.get handler doesn't refer to the element of the current iteration. Each function has it's own this value. You have several options.
Use the second parameter of the each callback.
$('.add-remove-permissoion').each(function(index, element) {
Use $.proxy or Function.prototype.bind method for setting the this value of the handler.
$.get('my-url', function(data) {
// ...
}.bind(this));
Cache the this value of the each handler and use it in your $.get handler.
var elem = this;
$.get('my-url', function(data) {
// ...
$(elem)...
});
Also note that there is a syntax error in your code:
$.get('my-url'}, function(data){
// -----------^
Problem is $(this) within ajax call does not refer to the button clicked.
Replace $(this).addClass with myElement.addClass. Create myElement within click event just before the ajax call: var myElement = $(this).

Grab URL parameter onclick of url.. Jquery, Javascript

I am having some trouble trying to store the url parameters of some dynamic links that I created with an ajax post response. The ajax post is working correctly and the name and subgenre vars are being properly filled from the ajax response. Now what I would like to happen is that a user clicks on one of the generated urls, the parameters inside of the urls, i.e. subgenre="blah", are going to be sent to a database and stored. The problem I am having is that a standard event click function will not work inside or outside of the document ready function.
$(document).ready(function() {
$.each(data, function() {
$('#artist-suggestions').append('<li>' + this.name + this.new + '</li>');
});
});
I then created an onclick function, as below, but I can not use the "this" query because it is outside of the document scope. I had to put the onclick function outside of the document ready function or else it would not work.
function artistGen(){
alert('dfdsf');
};
What am I missing here or what am I doing wrong?
You can pass these in the onclick function when you make each element.
$(document).ready(function() {
$.each(data, function() {
artist = this.name;
$('#artist-suggestions').append('<li>' + this.name + this.new + '</li>');
});
})
;
function artistGen(Blah1, Blah2){
saveData(Blah1, Blah2);
alert('dfdsf');
};
In jQuery for dynamic elements you can use the click event in this way
$('#artist-suggestions li').on('click', 'a', function() {
// do something
});
or you can continue with the way you did, by using a function but just add a parameter to that function
like
function artistGen(Artist){
// do something
};
You need to remove the artistGen() function from the scope of the .load()
$(window).load(function(){
$('#artist-suggestions').append('<li>jim new</li>');
});
function artistGen(){
alert('dfdsf');
}
JSFIDDLE DEMO
That's just how it is a function called in those event attributes have to be defined globally(or defined right there) not in any wrapper function. A better solution would be to attach event handlers.
$(document).ready(function() {
function artistGen(){
alert(this.href);
};
$.each(data, function() {
var $li = $('<li>' + this.name + this.new + '</li>');
$li.find('a').on('click', artistGen);
$('#artist-suggestions').append($li)
});
});

.each() bind hover events and pass a variable to handler functions

I'm trying to bind a hover event to some elements, walking through them with $.each, with the peculiarity that I want to pass a css classname as a parameter of the hover's handler functions, but it seems that the scope is not the one I'm expecting. I've tried to
$(document).ready(function () {
var $madewithLabels = $("#made-with .label");
// Binding
$madewithLabels.each(function (index) {
// get bootstrap css classname for the current element in the loop
var bsClass = getHoverClass($(this));
console.info("css class is: " + bsClass + " - " + typeof(bsClass));
$(this).hover(
function (bsClass) {
console.info(bsClass);
$(this).addClass(bsClass);
},
function (bsClass) {
console.info(bsClass);
$(this).removeClass(bsClass);
}
);
});
});
1st console.info: getHover() gets the right css class name (string) when the events are bound (on document ready)
2nd/3rd console.info: when hover's handler functions are executed bsClass is an object (I guess it's a jQuery one)
I've solved it this way:
$(document).ready(function () {
var $madewithLabels = $("#made-with .label");
// Binding
$madewithLabels.each(function (index) {
$(this).hover(
function () {
$(this).addClass(getHoverClass($(this)));
},
function () {
$(this).removeClass(getHoverClass($(this)));
}
);
});
});
But my questions are...
Is using $(this) the right solution?
Why when I pass a string variable to the handler functions I get an object when the function is called? is it because some type casting? is it because closure scope?
Thanks to the jQuery gurus answering!
What you're getting in the hover callback is an Event object, as mentioned by the docs:
handlerIn
Type: Function( Event eventObject )
A function to execute when the mouse pointer enters the element.
So in your first example change:
function (bsClass) {
To this:
function () {
So you keep using the original bsClass that you calculated before.

Have the element who call my js function

I know my question have answer in the past but I don't have the vocabulary to find this.
I call a JavaScript function like this:
Voir +
This function change the state of the element .stats-table but I want to know which button have been clicked to call this function?
Better : can I have a jQuery object of this button?
Try to pass the this reference to know which button was clicked,
HTML:
Voir +
JS:
function showTable(selec,elem){
var currentElem = $(elem); //Clicked element
}
If you don't want to change the signature of the function and the way you invoke it (as others have suggested), you can use the global window.event to identify the clicked element:
function showTable(selector)
{
var clickedElement = window.event.target;
//...
}
See MDN.
When you use jQuery, you might consider refactor your code like this:
$(document).ready(function(){
$('.show-table-link').on('click', function(){
var $usedButton = $(this)
showTable('.stats-table')
}
})
Voir +
It's good practice to attach the on click handler instead of writing it inline. Further reading document.ready and jQuery event basics.
You can pass any value or id and your can identify the function
<script type="text/javascript">
function showTable(clss_name,fun_id)
{
if(fun_id=='A1')
{
alert("First function Executed");
}
if(fun_id=='A2')
{
alert("Second Function is executed");
}
}
</script>
......
......
......
Voir +
Voir2 +
If your function is like this:
function showTable(selec) {
// some code
}
You can get the clicked element like this, using this:
function showTable(selec) {
// some code
var clickedElem = this;
}

Javascript pass parameter to function

i try to pass paramater to function. When i click the div it will alert the paramater that i pass
i have 2 file
index.html
script.js
here's what i try
Example 1
index.html
<div id="thediv" >
script.js
window.onload = initialize;
//bind event listener
function initialize(){
document.getElementById("thediv").onclick = myFunction(" something ");
}
//end of bind
//function
function myFunction(parameter) { alert( parameter ) };
//end of all function
the trouble is the function its executed without click
Example 2
index.html
<div id="thediv" onclick="myfunction('something')" >
script.js
function myFunction(parameter) { alert( parameter ) };
yap its done with this but the trouble if i have many element in index.html it will painful to read which element have which listener
i want to separate my code into 3 section (similiar with example1)
the view(html element)
the element have which listener
the function
what should i do? or can i do this?
(i don't want to use another library)
Placing () (with any number of arguments in it) will call a function. The return value (undefined in this case) will then be assigned as the event handler.
If you want to assign a function, then you need to pass the function itself.
...onclick = myFunction;
If you want to give it arguments when it is called, then the easiest way is to create a new function and assign that.
...onclick = function () {
myFunction("arguments");
};
Your first solution logic is absolutely ok .. just need to assign a delegate ... what you are doing is calling the function .. So do something like this ...
//bind event listener
function initialize(){
document.getElementById("thediv").onclick = function () { myFunction(" something "); };
}
//end of bind
Instead of assign you invoke a function with myFunction();
Use it like this
//bind event listener
function initialize(){
document.getElementById("thediv").onclick = function(){
myFunction(" something ");
}
}

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