Trigger OnChange when field is filed automatically? - javascript

I want to trigger a function when one of my field (textbox) changed. The problem is: the content of that textbox is filed automatically by an external script(That I don't have access to), therefore the onChange listener won't trigger.
I've tried a lot of code, but here's the two closest (I think?) result I have:
Here's the script and the field
<script async src="SomeNiceScriptHere.js"></script>
<input type="text" name="wt_embed_output" id="wt_embed_output" class="wt_embed_output"/>
Code 1:
function myFunction() {
var x = document.getElementById("wt_embed_output").value;
alert("The input value has changed. The new value is: " + x);
}
document.getElementById("wt_embed_output").addEventListener("change", myFunction);
Code 2:
$( "#wt_embed_output" ).change(function() {
alert( "Value has been changed" );
});
For now, it doesn't work when the value is updated with the script, it only works when the user manually changes the value.
Does anyone know a way to do it?

Try adding event listener in the input.
var el = document.getElementById('wt_embed_output');
el.value = 'New Value'
el.dispatchEvent(new Event('oninput'));
document.getElementById("wt_embed_output").addEventListener("oninput", myFunction());
function myFunction() {
var x = document.getElementById("wt_embed_output").value;
alert("The input value has changed. The new value is: " + x);
}
<input type="text" name="wt_embed_output" id="wt_embed_output" class="wt_embed_output" />

onchange only occurs when the change to the input element is committed by the user, most of the time this is when the element loses focus.
try using oninput event;
if that doesn't work you can use a solution that works for all cases: set up a timing event using setInterval()

This isn't a perfect solution, but it works. Since I wasn't able to fetch the text in the field right after the script execute, I did a little workaround with myFunction():
<script>
function myFunction() {
if(document.getElementsByClassName('wt_embed__message')[0].getElementsByClassName('main')[0].textContent != 'Upload completed!'){
setTimeout(myFunction, 500);
}
else{
var wt_output = document.getElementById("wt_embed_output").value;
//do something
}
}
window.addEventListener("load", myFunction);
</script>
-> When the page load, my function is called until the external scripts runs. Once I get a specified message, I know the script is done so I get out of the 'if' condition.

Related

Auto search after barcode/qrcode scanner update values into input? [duplicate]

I want to fire the JQuery change event when the input text is changed programmatically, for example like this:
$("input").change(function(){
console.log("Input text changed!");
});
$("input").val("A");
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<input type='text' />
But it doesn't work. How can I make this work?
change event only fires when the user types into the input and then loses focus.
You need to trigger the event manually using change() or trigger('change')
$("input").change(function() {
console.log("Input text changed!");
});
$("input").val("A").change();
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<input type='text' />
The event handler .change() behaves like a form submission - basically when the value changes on submit the console will log. In order to behave on text input you would want to use input, like below:
$("input").on('input', function(){
console.log("Input text changed!");
});
$("input").val("A");
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<input type='text' />
What you need to do is trigger the change event after you've set the text. So you may create a function to do that so you won't have to repeat it every time you need to update the text, like this:
function changeTextProgrammatically(value) {
$("input").val( value );
$("input").trigger( 'change' ); // Triggers the change event
}
changeTextProgrammatically( "A" );
I've updated the fiddle,
You can use the DOMSubtreeModified event:
$('input').bind('DOMSubtreeModified',function(){...})
If you want to fire both user and code changes:
$('input').bind('input DOMSubtreeModified',function(){...})
This event is marked as deprecated and sometimes quite CPU time consuming, but it may be also very efficient when used carefully...
jquery change event only works when the user types into the input and then loses focus. So you can use the following workaround to do so:-
Let's say you have a button clicking on which results in change in value of input. (this could be anything else as well instead of a button)
var original_value = $('input').val();
$('button').click(function(){
var new_value = $('input').val();
if(original_value != new_value ){
//do something
}
//now set the original value to changed value (in case this is going to change again programatically)
original_value = new_value;
})

Retrieve .val() from inputs on .focusout()

I have a series of dynamically generated inputs with the same class, eg:
<input class="addressitem" type="text"/>
<input class="addressitem" type="text"/>
<input class="addressitem" type="text"/>
After the user inputs data into each field I want to take that data and place it in the value field of a hidden input.
However, I am having trouble figuring out the best way to do this. So far I've tried:
$(".addressitem").focusout(function() {
var addressinput = $(this).val();
console.log(addressinput);
});
and
$(".addressitem").change(function() {
var addressinput = $(this).val();
console.log(addressinput);
});
But I cannot get anything to appear in console.
Could anyone point me in the right direction?
Both of your approaches should work as long as you define them inside the document.ready event and you do not have any other script errors in your page.
$(function(){
$(".addressitem").change(function() {
var addressinput = $(this).val();
console.log(addressinput);
});
$(".addressitem").focusout(function() {
var addressinput = $(this).val();
console.log(addressinput);
});
});
You may use your browser console to verify the existence of other script errors in the page.
Also remember that, change event occurs on the text input fields when the focus is out. So you will see the console.log when user changes the focus from the textboxes. If you want instant updates, you should consider using keyUp event
Here is a working sample.
EDIT : As per the comment : I had the fields generated by a Jquery click function. I had to move my code within the click function for it to work.
No you don't need to. You can simply use the jQuery on delegation method. When you register an event handler with jQuery on, It will work for current and future elements(dynamically injected) in the DOM.
So your code will be
$(function(){
$(document).on("change",".addressitem",function() {
var addressinput = $(this).val();
console.log(addressinput);
});
});
This might be the best option, as you said they are dynamically generated inputs.
$(document).on("blur",".addressitem",function() {
var addressinput = $(this).val();
console.log(addressinput);
});
WORKING FIDDLE
Check your console
On focusout in HTML5 as following:
<input type="text" onfocusout="makeITUpperCase(this)">
And in javascript as following:
function makeITUpperCase(e) {
console.log(e.value);
e.value = e.value.toUpperCase();
}
The function takes 'this' object as e which can be used to get value or alter

How to call a function when default browser autocomplete list item selected [duplicate]

I have a pretty simple form. When the user types in an input field, I want to update what they've typed somewhere else on the page. This all works fine. I've bound the update to the keyup, change and click events.
The only problem is if you select an input from the browser's autocomplete box, it does not update. Is there any event that triggers when you select from autocomplete (it's apparently neither change nor click). Note that if you select from the autocomplete box and the blur the input field, the update will be triggered. I would like for it to be triggered as soon as the autocomplete .
See: http://jsfiddle.net/pYKKp/ (hopefully you have filled out a lot of forms in the past with an input named "email").
HTML:
<input name="email" />
<div id="whatever"><whatever></div>
CSS:
div {
float: right;
}
Script:
$("input").on('keyup change click', function () {
var v = $(this).val();
if (v) {
$("#whatever").text(v);
}
else {
$("#whatever").text('<whatever>');
}
});
I recommending using monitorEvents. It's a function provide by the javascript console in both web inspector and firebug that prints out all events that are generated by an element. Here's an example of how you'd use it:
monitorEvents($("input")[0]);
In your case, both Firefox and Opera generate an input event when the user selects an item from the autocomplete drop down. In IE7-8 a change event is produced after the user changes focus. The latest Chrome does generate a similar event.
A detailed browser compatibility chart can be found here:
https://developer.mozilla.org/en-US/docs/Web/Events/input
Here is an awesome solution.
$('html').bind('input', function() {
alert('test');
});
I tested with Chrome and Firefox and it will also work for other browsers.
I have tried a lot of events with many elements but only this is triggered when you select from autocomplete.
Hope it will save some one's time.
Add "blur". works in all browsers!
$("input").on('blur keyup change click', function () {
As Xavi explained, there's no a solution 100% cross-browser for that, so I created a trick on my own for that (5 steps to go on):
1. I need a couple of new arrays:
window.timeouts = new Array();
window.memo_values = new Array();
2. on focus on the input text I want to trigger (in your case "email", in my example "name") I set an Interval, for example using jQuery (not needed thought):
jQuery('#name').focus(function ()
{
var id = jQuery(this).attr('id');
window.timeouts[id] = setInterval('onChangeValue.call(document.getElementById("'+ id +'"), doSomething)', 500);
});
3. on blur I remove the interval: (always using jQuery not needed thought), and I verify if the value changed
jQuery('#name').blur(function ()
{
var id = jQuery(this).attr('id');
onChangeValue.call(document.getElementById(id), doSomething);
clearInterval(window.timeouts[id]);
delete window.timeouts[id];
});
4. Now, the main function which check changes is the following
function onChangeValue(callback)
{
if (window.memo_values[this.id] != this.value)
{
window.memo_values[this.id] = this.value;
if (callback instanceof Function)
{
callback.call(this);
}
else
{
eval( callback );
}
}
}
Important note: you can use "this" inside the above function, referring to your triggered input HTML element. An id must be specified in order to that function to work, and you can pass a function, or a function name or a string of command as a callback.
5. Finally you can do something when the input value is changed, even when a value is selected from a autocomplete dropdown list
function doSomething()
{
alert('got you! '+this.value);
}
Important note: again you use "this" inside the above function referring to the your triggered input HTML element.
WORKING FIDDLE!!!
I know it sounds complicated, but it isn't.
I prepared a working fiddle for you, the input to change is named "name" so if you ever entered your name in an online form you might have an autocomplete dropdown list of your browser to test.
Detecting autocomplete on form input with jQuery OR JAVASCRIPT
Using: Event input. To select (input or textarea) value suggestions
FOR EXAMPLE FOR JQUERY:
$(input).on('input', function() {
alert("Number selected ");
});
FOR EXAMPLE FOR JAVASCRIPT:
<input type="text" onInput="affiche(document.getElementById('something').text)" name="Somthing" />
This start ajax query ...
The only sure way is to use an interval.
Luca's answer is too complicated for me, so I created my own short version which hopefully will help someone (maybe even me from the future):
$input.on( 'focus', function(){
var intervalDuration = 1000, // ms
interval = setInterval( function(){
// do your tests here
// ..................
// when element loses focus, we stop checking:
if( ! $input.is( ':focus' ) ) clearInterval( interval );
}, intervalDuration );
} );
Tested on Chrome, Mozilla and even IE.
I've realised via monitorEvents that at least in Chrome the keyup event is fired before the autocomplete input event. On a normal keyboard input the sequence is keydown input keyup, so after the input.
What i did is then:
let myFun = ()=>{ ..do Something };
input.addEventListener('change', myFun );
//fallback in case change is not fired on autocomplete
let _k = null;
input.addEventListener( 'keydown', (e)=>_k=e.type );
input.addEventListener( 'keyup', (e)=>_k=e.type );
input.addEventListener( 'input', (e)=>{ if(_k === 'keyup') myFun();})
Needs to be checked with other browser, but that might be a way without intervals.
I don't think you need an event for this: this happens only once, and there is no good browser-wide support for this, as shown by #xavi 's answer.
Just add a function after loading the body that checks the fields once for any changes in the default value, or if it's just a matter of copying a certain value to another place, just copy it to make sure it is initialized properly.

How to fire JQuery change event when input value changed programmatically?

I want to fire the JQuery change event when the input text is changed programmatically, for example like this:
$("input").change(function(){
console.log("Input text changed!");
});
$("input").val("A");
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<input type='text' />
But it doesn't work. How can I make this work?
change event only fires when the user types into the input and then loses focus.
You need to trigger the event manually using change() or trigger('change')
$("input").change(function() {
console.log("Input text changed!");
});
$("input").val("A").change();
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<input type='text' />
The event handler .change() behaves like a form submission - basically when the value changes on submit the console will log. In order to behave on text input you would want to use input, like below:
$("input").on('input', function(){
console.log("Input text changed!");
});
$("input").val("A");
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<input type='text' />
What you need to do is trigger the change event after you've set the text. So you may create a function to do that so you won't have to repeat it every time you need to update the text, like this:
function changeTextProgrammatically(value) {
$("input").val( value );
$("input").trigger( 'change' ); // Triggers the change event
}
changeTextProgrammatically( "A" );
I've updated the fiddle,
You can use the DOMSubtreeModified event:
$('input').bind('DOMSubtreeModified',function(){...})
If you want to fire both user and code changes:
$('input').bind('input DOMSubtreeModified',function(){...})
This event is marked as deprecated and sometimes quite CPU time consuming, but it may be also very efficient when used carefully...
jquery change event only works when the user types into the input and then loses focus. So you can use the following workaround to do so:-
Let's say you have a button clicking on which results in change in value of input. (this could be anything else as well instead of a button)
var original_value = $('input').val();
$('button').click(function(){
var new_value = $('input').val();
if(original_value != new_value ){
//do something
}
//now set the original value to changed value (in case this is going to change again programatically)
original_value = new_value;
})

Can jQuery check whether input content has changed?

Is it possible to bind javascript (jQuery is best) event to "change" form input value somehow?
I know about .change() method, but it does not trigger until you (the cursor) leave(s) the input field. I have also considered using .keyup() method but it reacts also on arrow keys and so on.
I need just trigger an action every time the text in the input changes, even if it's only one letter change.
There is a simple solution, which is the HTML5 input event. It's supported in current versions of all major browsers for <input type="text"> elements and there's a simple workaround for IE < 9. See the following answers for more details:
jQuery keyboard events
Catch only keypresses that change input?
Example (except IE < 9: see links above for workaround):
$("#your_id").on("input", function() {
alert("Change to " + this.value);
});
Yes, compare it to the value it was before it changed.
var previousValue = $("#elm").val();
$("#elm").keyup(function(e) {
var currentValue = $(this).val();
if(currentValue != previousValue) {
previousValue = currentValue;
alert("Value changed!");
}
});
Another option is to only trigger your changed function on certain keys. Use e.KeyCode to figure out what key was pressed.
You can also store the initial value in a data attribute and check it against the current value.
<input type="text" name="somename" id="id_someid" value="" data-initial="your initial value" />
$("#id_someid").keyup(function() {
return $(this).val() == $(this).data().initial;
});
Would return true if the initial value has not changed.
function checkChange($this){
var value = $this.val();
var sv=$this.data("stored");
if(value!=sv)
$this.trigger("simpleChange");
}
$(document).ready(function(){
$(this).data("stored",$(this).val());
$("input").bind("keyup",function(e){
checkChange($(this));
});
$("input").bind("simpleChange",function(e){
alert("the value is chaneged");
});
});
here is the fiddle http://jsfiddle.net/Q9PqT/1/
You can employ the use of data in jQuery and catch all of the events which then tests it against it's last value (untested):
$(document).ready(function() {
$("#fieldId").bind("keyup keydown keypress change blur", function() {
if ($(this).val() != jQuery.data(this, "lastvalue") {
alert("changed");
}
jQuery.data(this, "lastvalue", $(this).val());
});
});
This would work pretty good against a long list of items too. Using jQuery.data means you don't have to create a javascript variable to track the value. You could do $("#fieldId1, #fieldId2, #fieldId3, #fieldId14, etc") to track many fields.
UPDATE: Added blur to the bind list.
I had to use this kind of code for a scanner that pasted stuff into the field
$(document).ready(function() {
var tId,oldVal;
$("#fieldId").focus(function() {
oldVal = $("#fieldId").val();
tId=setInterval(function() {
var newVal = $("#fieldId").val();
if (oldVal!=newVal) oldVal=newVal;
someaction() },100);
});
$("#fieldId").blur(function(){ clearInterval(tId)});
});
Not tested...
I don't think there's a 'simple' solution. You'll probably need to use both the events onKeyUp and onChange so that you also catch when changes are made with the mouse. Every time your code is called you can store the value you've 'seen' on this.seenValue attached right to the field. This should make a little easier.
You can set events on a combination of key and mouse events, and onblur as well, to be sure. In that event, store the value of the input. In the next call, compare the current value with the lastly stored value. Only do your magic if it has actually changed.
To do this in a more or less clean way:
You can associate data with a DOM element (lookup api.jquery.com/jQuery.data ) So you can write a generic set of event handlers that are assigned to all elements in the form. Each event can pass the element it was triggered by to one generic function. That one function can add the old value to the data of the element. That way, you should be able to implement this as a generic piece of code that works on your whole form and every form you'll write from now on. :) And it will probably take no more than about 20 lines of code, I guess.
An example is in this fiddle: http://jsfiddle.net/zeEwX/
Since the user can go into the OS menu and select paste using their mouse, there is no safe event that will trigger this for you. The only way I found that always works is to have a setInterval that checks if the input value has changed:
var inp = $('#input'),
val = saved = inp.val(),
tid = setInterval(function() {
val = inp.val();
if ( saved != val ) {
console.log('#input has changed');
saved = val;
},50);
You can also set this up using a jQuery special event.

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