I have the following code:
checkbox.addEventListener('mousedown', function () {
if (!this.checked) {
this.checked = true;
}
});
It should turn on the checkbox when mouse button is down.
And it works perfectly but when I release the button, the checkbox turns back off. How can i fix this?
checkbox.addEventListener('mousedown', function(){
if(!this.checked) {
var preventUnselect = function(){
this.checked = true;
checkbox.removeEventListener('click', preventUnselect)
};
checkbox.addEventListener('click', preventUnselect)
this.checked = true;
}
});
<input type="checkbox" id="checkbox"/>
I'm pretty sure that your checkbox gets unchecked because default behavior of checkbox is to change it's state after click. If you check checkbox after mousedown, then it's state get switched(turned back to unchecked) after click event completes. Just click the checkbox and move the pointer outside of it while still holding left mouse key down - checkbox won't get unchecked when you release the button..
You have to bind click event after mousedown, and remove that event afterward. If event wasn't removed your checkbox would be checked forever.
checkbox.addEventListener('mousedown', function(){
this.checked = !this.checked;
});
Note that checkboxes already have this behaviour as a default built into it by the browsers. I you want to see if a checkbox is checked or not you can simply look at the checked property of the DOM element. For example:
const checkbox = document.getElementById('Mycheckbox');
// this onclick now purely for demonstration purposes
checkbox.addEventListener('click', function () {
console.log(checkbox.checked);
});
<input type="checkbox" id="Mycheckbox"/>
Related
I have a couple of checkboxes and a button. When I click on checkbox - function is triggered. This is the desired behavior but I want to trigger it by clicking on the button. I want to have the possibility to first select checkboxes (I tried with return false and event.preventDefault but these completely switch the selection off) and then by clicking the button - trigger functions from checkboxes. Here is a link to jsfiddle:
http://jsfiddle.net/j93k2xns/6/
So for instance: I can select 3 checkboxes (nothing should happen) and after I click the button - three alerts should appear.
The code:
HTML:
<input type="checkbox" name='check[]' id="first">first</input>
<input type="checkbox" name='check[]'>second</input>
<input type="checkbox" name='check[]'>third</input>
<input type="checkbox" name='check[]'>fourth</input>
<input type="button" value="validate" id="val-button">
JS:
var check_state;
$(document).on('click','input[name="check[]"]', function(e){
if(check_state === true) {
alert('a');
} else {
return false;
}
});
$(document).on('click','#val-button', function(){
check_state = true;
});
There are a few interpretations to his question. If I'm reading it correctly, he wants to bind an arbitrary function to the checkboxes. Clicking the button should fire this event. This is how you can achieve that using custom events in jQuery:
$(function () {
$("input[name='check[]']").bind("myCustomButtonClick", function() {
if(this.checked) {
alert('a');
}
});
})
$(document).on('click','#val-button', function(){
$("input[name='check[]']").trigger("myCustomButtonClick");
});
And the associated jsfiddle: http://jsfiddle.net/3yf7ymos/
$(document).on('click','#val-button', function(){
$( 'input[name="check[]"]' ).each(function( index ) {
if($(this).is(':checked')) {
alert("a");
return true;
}
});
});
If you want to do something when the user checks a checkbox, add an event listener:
$('input[type="checkbox"]').click(function() {
if ($(this).is(':checked')) {
// do something
}
});
If the idea is run a couple of functions after the inputs are checked by clicking on a button:
function myFunction() {
if ($('input[id="something"]:checked').length == 0) {
// do something
} else if ($('input[id="something_2"]:checked').length == 0) {
// do something
}
//and so on..
}
$('#val-button').click(function() {
myFunction();
});
I have a similar inquiry. I have a number of check boxes. Each checkbox is linked to a different URL that opens a PDF form. I want my team to be able to select which forms they need by ticking the checkbox. Once they have done that, I would like a button to trigger the opening of each form based on which check box is checked. I have it so the checkbox upon being checked opens the form right away but it is very distracting. Its preferable they all get opened at once by a "button". Help. I am quite new to JavaScript so may need additional clarity.
I'm using some JQ stuff on check box, even if the parent div is clicked. I am toggling the value of check box. Clicking on div is working perfectly but when you click on checkbox the function is called twice. Is there any way to solve this problem? following is my code(Fiddle)
HTML:
<div class="check-unit">
<input type="checkbox" class="check" />
<p class="brandList">Model</p>
</div>
JQ:
$('.check').on('change',function(e){
e.stopImmediatePropagation();
if($(this).is(':checked')){
console.log("checked");
}else{
console.log("unchecked");
}
});
$('.check-unit').on('click',function(e){
var checkbox = $(this).children('.check'),
chhhk= checkbox.attr('checked') ? false : true;
checkbox.attr('checked',chhhk);
$(this).children('.check').change();
});
I've seen eventbubbling problem on stackoverflow, but still confused how to do this. FIDDLE
Only execute the callback on the parent element if the target is not the input
$('.check').on('change',function(e){
if(this.checked){
console.log("checked");
}else{
console.log("unchecked");
}
});
$('.check-unit').on('click',function(e){
if ( ! $(e.target).hasClass('check')) {
$(this).children('.check').prop('checked', function(_,state) {
return !state;
}).trigger('change');
}
});
FIDDLE
As a sidenote, this is what label elements are for!
You need to use .prop() instead of .attr() to set the checked property.
$('.check').on('change', function (e) {
if (this.checked) {
console.log("checked");
} else {
console.log("unchecked");
}
}).click(function (e) {
//prevent clicks in the checksboxes from bubbling up otherwise when you click on the checkbox the state will get toggled again the event will be bubbled to check-unit which will again toggle the state negating the click
e.stopPropagation()
});
$('.check-unit').on('click', function () {
var checkbox = $(this).children('.check'),
//use .is() and checked-selector to check whether the checkbox is checked
chhhk = checkbox.is(':checked');
//use .prop() instead of .attr() & toggle the checked state
checkbox.prop('checked', !chhhk).change();
});
Demo: Fiddle
You can check if you are clicking the checkbox before changing.
$('.check-unit').on('click', function (e) {
if (!($(e.target).hasClass('check'))) {
var checkbox = $(this).children('.check'),
chhhk = checkbox.prop('checked');
checkbox.prop('checked', !chhhk).change();
}
});
Also note that the code is using prop instead of attr because when you are using boolean attribute values you should use .prop()
DEMO
i want do something like this with a checkBox. if the user clicks on the checkbox, it should change its state (checked -> unchecked and vv. ).
my code:
$('#checkBoxStandard').change(function() {
clickedFormBoxen('standard');
});
function clickedFormBoxen(active){
if(active == 'standard'){
if( $('#checkBoxStandard').is(":checked")){
$('#checkBoxStandard').prop("checked", false);
}else{
$('#checkBoxStandard').prop("checked", true);
}
console.log('ac: '+$('#checkBoxStandard').is(':checked'));
}
Unfortunately, the checkbox will not be unchecked again. The fist time, the checkbox is getting checked, but if i click on it again, nothing happens, it's still checked.
I wish to use this code so i can change the state of the checkbox by function call and not just by user interaction.
Please help me and sorry for my english^^
Try
$('#checkBoxStandard').removeAttr("checked");
You mean something like this? (jsFiddle)
HTML
<input type="checkbox" id="checkbox">
<label for="checkbox">Hey,check me!</label>
JavaScript
var respond = true;
function manualCheck(state)
{
respond = false;
$('#checkbox').prop("checked", state);
}
$('#checkbox').change(function ()
{
if (!respond)
{
respond = true;
return;
}
// Your code
}
As i've mentionend in my comment to your question, with your function clickedFormBoxen you effectively revert the effect of a user interaction on the checkbox element. Thus it seems that you have to call the change handler from a click handler on your checkbox element (i've streamlined the code a bit):
function clickedFormBoxen(active) {
if (active == 'standard') {
$('#checkBoxStandard').prop("checked", !($('#checkBoxStandard').prop("checked")));
}
}
$(document).ready( function(){
$('#checkBoxStandard').change( function(e) {
clickedFormBoxen('standard');
1;
});
$('#checkBoxStandard').click(function(e) {
$('#checkBoxStandard').change();
1;
});
});
This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
JQuery $(#radioButton).change(…) not firing during de-selection
I have the following HTML/jQuery:
<input id="rb1" type="radio" name="rb" checked="true">
<input id="rb2" type="radio" name="rb">
$("#rb2").change(function () {
if ($(this).is(":checked")) {
alert('checked');
}
else {
alert('unchecked');
}
});
When my rb2 radio button is unselected by selecting rb1, the change event does not fire. Why is this? Is it possible to get this working without changing my selector to match both inputs and then looking at the ID?
Fiddle: http://jsfiddle.net/4uRWR/
The change event only gets sent when you actually modify the item itself. When you click the other radio, you aren't modifying it. A fix would be to watch the change event on every input:radio, then just check the state of the relevant radio button:
$("input:radio").change(function () {
if ($("#rb2").is(":checked")) {
alert('checked');
}
else {
alert('unchecked');
}
});
http://codepen.io/AlienHoboken/pen/akwjB
Listen for change on every input related to your group of radios and then check if a specific one is selected.
$("input[name=rb]").change(function () {
if ($('#rb2').is(":checked")) {
alert('checked');
} else {
alert('unchecked');
}
});
http://jsfiddle.net/4uRWR/2/
You can artificially trigger a "change" on radio buttons from the same group so that the original bound handler would get picked up and output "unchecked". The trick is to avoid being stuck in an infinite loop by recursively re-triggering the event, we can avoid that by ignoring artificial events that lack the originalEvent property:
$("input[type=radio]").on("change", function (e) {
var $this = $(this);
//all inputs with the same name
var $targetInputSelector = $("input[name=" + $this.attr("name") + "]");
//check if the handler was fired "naturally"
//if yes, trigger the change handler "artificially" for inputs with the same name
if (e.hasOwnProperty('originalEvent')) {
//exclude the element that was changed "naturally"
//from the subset of all the elements with the same name
$targetInputSelector.not($this).triggerHandler("change");
}
});
This code works when added on top of your current handler and satisfies the without changing my selector to match both inputs and then looking at the ID criteria ;)
http://jsfiddle.net/a73tn/24/
I sorta ran into this issue a few days ago. Instead of listening for an individual click on a radio button, I listen for a click on the <ul> I have them in and then call this function to check if one has been selected.
// Iterate over the radio group and determine if one of them is selected
function loopRadBtns(btnGroup)
{
var isChecked = false;
btnGroup.find('input[type="radio"]').each(function()
{
if($(this).attr('checked'))
{
isChecked = true;
}
});
return isChecked;
}
How can a checkbox be checked/unchecked using JavaScript?
Javascript:
// Check
document.getElementById("checkbox").checked = true;
// Uncheck
document.getElementById("checkbox").checked = false;
jQuery (1.6+):
// Check
$("#checkbox").prop("checked", true);
// Uncheck
$("#checkbox").prop("checked", false);
jQuery (1.5-):
// Check
$("#checkbox").attr("checked", true);
// Uncheck
$("#checkbox").attr("checked", false);
Important behaviour that has not yet been mentioned:
Programmatically setting the checked attribute, does not fire the change event of the checkbox.
See for yourself in this fiddle:
http://jsfiddle.net/fjaeger/L9z9t04p/4/
(Fiddle tested in Chrome 46, Firefox 41 and IE 11)
The click() method
Some day you might find yourself writing code, which relies on the event being fired. To make sure the event fires, call the click() method of the checkbox element, like this:
document.getElementById('checkbox').click();
However, this toggles the checked status of the checkbox, instead of specifically setting it to true or false. Remember that the change event should only fire, when the checked attribute actually changes.
It also applies to the jQuery way: setting the attribute using prop or attr, does not fire the change event.
Setting checked to a specific value
You could test the checked attribute, before calling the click() method. Example:
function toggle(checked) {
var elm = document.getElementById('checkbox');
if (checked != elm.checked) {
elm.click();
}
}
Read more about the click method here:
https://developer.mozilla.org/en-US/docs/Web/API/HTMLElement/click
to check:
document.getElementById("id-of-checkbox").checked = true;
to uncheck:
document.getElementById("id-of-checkbox").checked = false;
We can checked a particulate checkbox as,
$('id of the checkbox')[0].checked = true
and uncheck by ,
$('id of the checkbox')[0].checked = false
Try This:
//Check
document.getElementById('checkbox').setAttribute('checked', 'checked');
//UnCheck
document.getElementById('chk').removeAttribute('checked');
I would like to note, that setting the 'checked' attribute to a non-empty string leads to a checked box.
So if you set the 'checked' attribute to "false", the checkbox will be checked. I had to set the value to the empty string, null or the boolean value false in order to make sure the checkbox was not checked.
Using vanilla js:
//for one element:
document.querySelector('.myCheckBox').checked = true //will select the first matched element
document.querySelector('.myCheckBox').checked = false//will unselect the first matched element
//for multiple elements:
for (const checkbox of document.querySelectorAll('.myCheckBox')) {
//iterating over all matched elements
checkbox.checked = true //for selection
checkbox.checked = false //for unselection
}
function setCheckboxValue(checkbox,value) {
if (checkbox.checked!=value)
checkbox.click();
}
<script type="text/javascript">
$(document).ready(function () {
$('.selecctall').click(function (event) {
if (this.checked) {
$('.checkbox1').each(function () {
this.checked = true;
});
} else {
$('.checkbox1').each(function () {
this.checked = false;
});
}
});
});
</script>
For single check try
myCheckBox.checked=1
<input type="checkbox" id="myCheckBox"> Call to her
for multi try
document.querySelectorAll('.imChecked').forEach(c=> c.checked=1)
Buy wine: <input type="checkbox" class="imChecked"><br>
Play smooth-jazz music: <input type="checkbox"><br>
Shave: <input type="checkbox" class="imChecked"><br>
If, for some reason, you don't want to (or can't) run a .click() on the checkbox element, you can simply change its value directly via its .checked property (an IDL attribute of <input type="checkbox">).
Note that doing so does not fire the normally related event (change) so you'll need to manually fire it to have a complete solution that works with any related event handlers.
Here's a functional example in raw javascript (ES6):
class ButtonCheck {
constructor() {
let ourCheckBox = null;
this.ourCheckBox = document.querySelector('#checkboxID');
let checkBoxButton = null;
this.checkBoxButton = document.querySelector('#checkboxID+button[aria-label="checkboxID"]');
let checkEvent = new Event('change');
this.checkBoxButton.addEventListener('click', function() {
let checkBox = this.ourCheckBox;
//toggle the checkbox: invert its state!
checkBox.checked = !checkBox.checked;
//let other things know the checkbox changed
checkBox.dispatchEvent(checkEvent);
}.bind(this), true);
this.eventHandler = function(e) {
document.querySelector('.checkboxfeedback').insertAdjacentHTML('beforeend', '<br />Event occurred on checkbox! Type: ' + e.type + ' checkbox state now: ' + this.ourCheckBox.checked);
}
//demonstration: we will see change events regardless of whether the checkbox is clicked or the button
this.ourCheckBox.addEventListener('change', function(e) {
this.eventHandler(e);
}.bind(this), true);
//demonstration: if we bind a click handler only to the checkbox, we only see clicks from the checkbox
this.ourCheckBox.addEventListener('click', function(e) {
this.eventHandler(e);
}.bind(this), true);
}
}
var init = function() {
const checkIt = new ButtonCheck();
}
if (document.readyState != 'loading') {
init;
} else {
document.addEventListener('DOMContentLoaded', init);
}
<input type="checkbox" id="checkboxID" />
<button aria-label="checkboxID">Change the checkbox!</button>
<div class="checkboxfeedback">No changes yet!</div>
If you run this and click on both the checkbox and the button you should get a sense of how this works.
Note that I used document.querySelector for brevity/simplicity, but this could easily be built out to either have a given ID passed to the constructor, or it could apply to all buttons that act as aria-labels for a checkbox (note that I didn't bother setting an id on the button and giving the checkbox an aria-labelledby, which should be done if using this method) or any number of other ways to expand this. The last two addEventListeners are just to demo how it works.
I agree with the current answers, but in my case it does not work, I hope this code help someone in the future:
// check
$('#checkbox_id').click()