Javascript event removing - javascript

Another Javascript , probobly for you minor problem , but i just can not understand how to fix it , googled all night for it , problem is simple ... i have table and inside td's i got buttons and i assigned onclick event on all of them , so when i click a button i do a function and at the end of function i want to change that event to go for another function
here is my code ...
var $UserRow = $(Final).closest('tr').clone();
$('td button', $UserRow).each(function () {
this.removeEventListener('click', GetInfo, false);
this.addEventListener('click', GetBetslip, false);
});
$UserRow.appendTo('#UserTicket');
So $UserRow is a row that i want to copy to another table and that part is working fine , but before i copy it i want to remove all button events ... i have tried with everything from
this.removeEventListener('click',GetInfo,false);
this.detachEvent('Click', GetInfo);
this.onclick = GetBetslip;
this.onclick = function () { GetBetslip()};
i just do not know what to try anymore ... can you just help me out ... all i want is to change event for every button inside that tr.

It looks like you are using jQuery, if that is the case you are looking for this function. $().off()
According to the comments you might do better with this:
$(this).attr('onclick', false);

If using jQuery, its preferable to bind AND unbind events using jQuery. You can use this method ONLY if you bind your handlers using jQuery:
Do this instead:
$('td button', $UserRow).each(function () {
$(this).off('click', GetInfo);
$(this).on('click', GetBetslip);
});

Related

onclick needs to be double clicked

When using onclick in JavaScript to call the function nowClicked(), I need to click the object twice in order for the alert to show. Below is the code for my function.
function nowClicked() {
$('.object').click(function() {
$('.object').removeClass("clicked");
var myClass = $(this).attr("id");
alert(myClass);
$(this).addClass("clicked");
e.stopImmediatePropagation();
});
};
What is the problem?
Here's what happens the first time you click your button:
nowClicked is called because you've set it up on the button's onclick
nowClicked sets up a jQuery click handler for .object
The code inside the jQuery click handler only runs the next time you click on the button.
It looks like you are mixing up two ways of handling clicks -- one is using the onclick event, and the second is using jQuery. You need to pick one and stick to it instead of using both.
There is no need to put it inside another function,because click is itself handling a callback function.Remove the outer function nowClicked else remove the $('.object').click(function() {.In the second case you may to pass the context as a function argument.
$('.object').click(function() {
$('.object').removeClass("clicked");
var myClass = $(this).attr("id");
alert(myClass);
$(this).addClass("clicked");
e.stopImmediatePropagation();
});

jQuery delete trigger conditionally

I was wondering if Javascript or jQuery have a way to delete an event listener. Let's say I want to make a function that I want to trigger only once, for example let's say I want to have a button that shows some hidden elements on the document, I would make this function (assuming the hidden elements have a hidden class that hides them):
jQuery('#toggler').click(function() {
console.log('Hidden elements are now shown');
jQuery('.hidden').removeClass('hidden');
});
Simple enough, right ? Now, my actual problem comes in, I don't want jquery to run that function again and again each time the button is clicked, because the elements are already revealed, so is there a clean way to do it ? So, in this example after clicking the toggler multiple times I want to get only one console message.
I could do jQuery(this).unbind('click'), but this results into removing ALL triggers and I only want to remove the current trigger.
What I usually do when I face such scenarios is solve it like this (which is ugly and doesn't actually prevent code execution, but only handles the code's results) :
var toggler_clicked = false;
jQuery('#toggler').click(function() {
if(toggler_clicked) return;
toggler_clicked = true;
console.log('Hidden elements are now shown');
jQuery('.hidden').removeClass('hidden');
});
Also I don't want to use jQuery's one, because I will have the same problem when I'll need to delete the trigger conditionally, so if you can help please give me a dynamic answer.
Thanks in advance !
You have to name your function like that:
var myFunction = function() {
console.log('Hidden elements are now shown');
jQuery('.hidden').removeClass('hidden');
};
And bind it this way
jQuery('#toggler').click(myFunction);
Then you can unbind it with :
jQuery('#toggler').off('click',myFunction);
Without unbinding the other listeners
You can try this:
var myFunc = function() {
console.log('Hidden elements are now shown');
jQuery('.hidden').removeClass('hidden');
jQuery(this).unbind('click', myFunc);
};
jQuery('#toggler').click(myFunc);
This way of calling unbind is such that only the listener for myFunc handler is removed and not all the events connected to the click on the toggler.
I would use the .on() and its opposite .off() methods to attach/detach the event handler. It is the recommended way since 1.7 instead of the .bind() and .unbind() versions that became deprecated as of jQuery 3.0.
$("#toggler").on("click", function(event) {
console.log('Hidden elements are now shown');
$('.hidden').removeClass('hidden');
// if (/* Add your condition here */) {
$(this).off(event);
// }
});
$("#toggler").on("click", function(event) {
console.log('Hidden elements are now shown');
$('.hidden').removeClass('hidden');
// if (/* Add your condition here */) {
$(this).off(event);
// }
});
.hidden {
display: none;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<button id="toggler">Toggle</button>
<div class="hidden">
HIDDEN
</div>
Try this
var myFunction = function() {
console.log('Hidden elements are now shown');
jQuery('.hidden').removeClass('hidden');
};
Add the event listener like this:
jQuery('#toggler').addEventListener("click", myFunction);
And remove it like this:
jQuery('#toggler').removeEventListener("click", myFunction);
So all together this will do the trick:
var myFunction = function() {
console.log('Hidden elements are now shown');
jQuery('.hidden').removeClass('hidden');
jQuery('#toggler').removeEventListener("click", myFunction);
};
jQuery('#toggler').addEventListener("click", myFunction);
more about the HTML DOM removeEventListener() Method
Jquery unbind function takes 2 parameters eventType and handler
You can put your event listener into separate function like this:
var clickEventHandler = function(){
//your logic goes here
}
After you add listener as reference:
jQuery('#toggler').click(clickEventHandler);
And then, later, anytime, anywhere you want you can unbind that specific handler:
jQuery('#toggler').unbind('click', clickEventHandler);
What i used to do in the past is toggle the click behavior using css classes, ex i used to set a click listener on the parent and delegate to all of the children something that jquery is doing now by default i believe. Anyway based on the css class it will trigger an event for ex.
$('.some-parent-element').on(
'click',
'the-behavior-css-class',
function() { // do stuff here.... }
)
Now if you want to remove this behavior you can just toggle the class of the element and it should do the job. ex
$('.some-parent-element').on(
'click',
'hide-me-on-click-or-whatever',
function() {
$(this).toggleClass('hide-me-on-click-or-whatever')
// perform the action
}
)
You can check if the element has the class hidden

is there a way to add multiple events to the $("body").on() to work when a list is changed or a button is clicked

I have the following script :-
$(document).ready(function () {
$("body").on('change', '#FilterSize1,#FilterSize2', function () {
where the related function will fire when the filterSize1 or FilerSize2 is changed. now I want to modify the above to allow the same function to fire when an button is clicked also ? so can anyone advice if $("body").on allow to define multiple events (when a list is changed or when a button is clicked ??) ?
Just name the function.
Although you can have .on("change click",function() - it looks strange when you have things that change and things that you click. For example if you click a select the function will be executed regardless of change. It does make it more readable too.
function something() {}
$(document).ready(function () {
$("body").on('change', '#FilterSize1,#FilterSize2', something);
$("body").on('click', '#button,#button1', something);
});
on neater:
$(document).ready(function () {
$("body").on('change', '#FilterSize1,#FilterSize2', something)
.on('click', '#button,#button1', something);
});
Use multiple events with space separated
$("body").on('change click', .......
In case you want different handlers for them then
$("body").on({'click': function(){ .... }, 'change' : function(){..........},'selector')
For binding events for separate elements, you should bind twice with different selectors
$("body").on('click','selector1',handler).on('change','selector2',handler)

jQuery on(click) doesn't work but on(hover) does

After initialize js I create new <div> element with close class and on("click") function doesn't work.
$(document).on('click', '.post-close', function () {
alert("hello");
});
but on('hover') work perfectly.
$(document).on('hover', '.post-close', function () {
alert("hello");
});
but I need to make it work on click.
It's because you're not preventing the default behaviour of the browser. Pass e into your handler and then use e.preventDefault()
$(document).on('click', '.post-close', function (e) {
e.preventDefault();
alert("hello");
});
Edit
Also, bind the handler before creating the new <div>
why not use something like
$('.post-close').click(function(){
//do something
});
If the element was added dynamically use:
$(document).on('click', '.post-close', function(){
//do something
});
edit:
like danWellman said, you can add the preventDefault IF you want to make sure no other code is executed. otherwise use the code above.
edit2:
changed the .live to .on
It's an old post but I've had a exactly same problem (element created dynamically, hover works, but click doesn't) and found solution.
I hope this post helps someone.
In my case, I found ui-selectable is used for parent element and that was preventing from click event propagate to the document.
So I added a selector of the button element to ui-selectable's 'cancel' option and problem solved.
If you have a similar probrem, check this
Try turn of libraries for parent element
You're not using stopPropagation() in parent element ?

Changing the onclick event delegate of an HTML button?

How do you change the JavaScript that will execute when a form button is clicked?
I've tried changing its onClicked and its onclicked child attributes like so:
$('mybutton').onClick = 'doSomething';
and
$('mybutton').attributes["onclick"] = 'doSomething()';
Neither seem to work. My other options are:
To have two buttons and hide one and show the other.
To have it directed to a function that evals a string and change the string to the function I want to execute.
Neither seem very elegant.
I'm using Prototype as a js library so it that has any useful tools I can use them.
If the original onclick event was set through HTML attributes, you can use the following to overwrite it:
$("#myButtonId").setAttribute("onclick", "myFunction();");
For Prototype, I believe that it would be something like this:
$("mybutton").observe('click', function() {
// do something here
});
EDIT: Or, as it says in the documentation, you could simply specify the function you want to call on click:
$('mybutton').observe('click', respondToClick);
function respondToClick(event) {
// do something here
}
But this is all, again, Prototype-specific.
Using the Prototype framework you can do:
Event.observe("mybutton", "click", clickHandler);
or:
Event.observe("mybutton", "click", function() {
alert("Button clicked!");
});
or:
$("mybutton").observe("click", clickHandler);
or:
$("mybutton").observe("click", function() {
alert("Button clicked!");
});
See the Event class documentation
The general way to set an onclick handler in javascript is to set onclick to a function, by passing it the name of a function directly, not in a string. So if myButton is set to a DOM Element, you would write:
myButton.onclick = doSomething;
So when you click the 'mybutton' button, the doSomething function will be called as doSomething(). For anonymous functions, you can write:
myButton.onclick = function() {
alert("myButton was clicked!");
};
In JQuery it's
$("#myButtonId").click(myFunction);
function myFunction(){
alert("Clicked");
}
Or if you want to put the function inline:
$("#myButtonId").click(function(){
alert("Clicked");
});
If you are using JQuery firstly make sure you use the relevant selector prefix (IE: If your using the Id of the element put a # in front of it). Secondly it's the click method to assign a callback to the click event.
Last I used Prototype, it was something like this:
Event.observe('mybutton', 'click', doSomething);
By the way, your examples might've even worked if you didn't quote the function names.
EDIT: Yes, Element.observe(element, eventName, handler) and someElement.observe(eventName, handler) also work. And don't quote the handler name - you want to pass the function not a string!
I found a solution for your issue with prototype under firefox:
$("#myButtonId").writeAttribute('onclick', ''); // first remove the attribute
$("#myButtonId").observe('click', function () { ... }); // then add the event

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