I have an <input type="text"> that have you value updated for many other scripts jQuerys, using the method .val("value here"). I need a new script to be run when the value of input has been updated. How to associate an event that'd make it for me?
Here is my code:
$('#PedidoTotalDescontoPadrao').change(function()
{
console.log('test');
});
but it doesn't work
I think you're using the wrong event handler for what you need.
Try this one.
http://api.jquery.com/keyup/
The change() method does not applies to <input type="text"> html tags. you may wan't to do it with keyup().
$('#PedidoTotalDescontoPadrao').keyup(function() {
console.log('test');
// and this is how you'd trigger the other events you want
$('.something').trigger('click');
});
Related
Please run this sample in Google Chrome browser.
Stack Snippet
$(function() {
$(":input").select(function() {
$("div").text("Something was selected").show().fadeOut(1000);
alert("Selected");
});
$("button").click(function() {
$(":input").select();
});
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.8.3/jquery.min.js"></script>
<button>Click To Select</button>
<input type="text" value="Some text">
<div></div>
Here why jQuery select event listener is triggering multiple times? Does anyone know the reason behind this? And is there any workaround solution for this without using timeout?
The $(":input") selector is selecting the button too, so it causes recursion. Either use just $("input"), or $(":input:not(button)").
I noticed when the three events are fired, the first doesn't have originalEvent property, so we definitely can dismiss it, and the second two has very similar (however not identical) timestamp. You can store the last timestamp in some variable and in event listener compare it with the event's timestamp. If the rounded values of these two are the same, you can dismiss this event.
$(function() {
var lastTimeStamp;
$("input").select(function(event) {
if (!event.originalEvent ||
lastTimeStamp === Math.round(event.timeStamp)) return;
lastTimeStamp = Math.round(event.timeStamp);
$("div").text("Something was selected").show().fadeOut(1000);
alert("Selected");
});
$("button").click(function() {
$("input").select();
});
});
See updated JS Fiddle.
It appears the issue is a combination of:
the :input selector gets the input and the button, hence multiple events triggered.
even when using just input as the selector there is some odd event propagation being triggered on related elements which is raising the select event handler multiple times.
To avoid both of the above, use input as the selector and also use preventDefault() in the event handler. stopPropagation() may also be required, depending on your HTML stucture.
$(function() {
$('input').select(function(e) {
// e.stopPropagation(); // optional
e.preventDefault();
$('#message').text("Something was selected").show().fadeOut(1000);
console.log('Selected');
});
$('button').click(function() {
$('input').select();
});
});
Working example
UPDATE: We were all fooled. The select() function needs a prevent default.
Rory McCrossan figured it out. Well done mate.
Incidentally, I'm not sure what the benefit of select() actually is! Something like focus() or on('focus',) might make more sense. Not Sure what the context is however. The below still follows:
Why waste time using generalised tag/type selectors which may change? Use an ID, and pick out only the one you want.
If you want to detect multiple, use a class. If you want to use multiple, but figure out which one you clicked, use a class and an ID. Bind with the class, and identify using $this.attr('id').
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.8.3/jquery.min.js"></script>
<button>Click To Select</button>
<input type="text" value="Some text" id="pick-me">
<div></div>
$(function() {
$("#pick-me").select(function(event) {
event.preventDefault();
$("div").text("Something was selected").show().fadeOut(1000);
alert("Selected");
});
$("button").click(function() {
$("#pick-me").select();
});
});
I have a form as follows:
<form>
<label for="input">Input:</label>
<input type="text" id="input" maxlength="3"></input>
<button type="button" id="lock" onMouseDown="toggleInput()"></button>
</form>
And javascript code:
function toggleInput(){
if ($("#input").disabled){
$("#input").disabled = false;
}
else {
$("#input").disabled = true;
};
}
What I basically want to do is to check what state (enabled/disabled) the textbox is in, and then toggle the state accordingly. I don't know if the javascript portion even uses the correct syntax to check if the textbox is disabled, but it's what I could think of.
Thanks in advance!
EDIT: Reason as to why I've chosen to use onmousedown instead of onclick to execute the event with the button:
I have chosen to use onmousedown instead of onclick as it makes the app I'm building feel less clunky due to the presence of this feature with onclick: When you click on a button and then drag the cursor away from the button while holding the mouse button down, and subsequently lift your finger off the mouse button when the cursor is in an area away from the button on the webpage, the event will not be executed. Hence, I've chosen to use onmousedown as this is overcome.
Use .prop(), Get the value of a property for the first element in the set of matched elements or set one or more properties for every matched element
$("#input").prop('disabled',!$("#input").prop('disabled'))
DEMO
I am not sure why you are using onMouseDown. Use click instead
$("#lock").on("click", function() {
$("#input").prop('disabled',!$("#input").prop('disabled'))
});
DEMO with click
To do it with jQuery try this:
$("#input").prop("disabled", function(i, v) { return !v; });
Your existing code doesn't work because DOM elements have a .disabled property, but jQuery objects do not.
I'm not sure why you're using onmousedown instead of onclick for the button, but either way if you're going to use jQuery I'd recommend removing the inline event attribute in favour of binding the handler with jQuery:
$("#lock").on("click", function() {
$("#input").prop("disabled", function(i, v) { return !v; });
});
(You'd need to include that code either in a script block at the end of the body or in a document ready handler.)
Demo: http://jsfiddle.net/a7f8v/
You should append the event handler with jQuery instead of an onMouseDown event. The syntax could look like this:
<label for="input">Input:</label>
<input type="text" id="input" maxlength="3"></input>
<button type="button" id="lock"></button>
JavaScript:
$(document).ready(function() {
$("#lock").click(function() {
var input = $("#input");
input.prop('disabled',!input.is(':disabled'))
});
});
Example
When I change the id of a button I cannot find the new id with on.("click"). The function console.log() does detect that it's changed but I cannot detect it with the on() function.
HTML:
<form id="formName" action="" method="post">
<input type="submit" id="submitBtn" value="Submit" />
</form>
<button id="change">Change</button>
JS:
$("#change").on("click", function(){
$("#submitBtn").attr("id", "NewBtn");
});
$("#formName").submit(function(e){
e.preventDefault();
});
$("#NewBtn").on("click", function(){
alert("Hello");
});
So I need it to alert "Hello" after I have clicked on change. It does change the id I checked that with inspect element.
Fiddle: http://jsfiddle.net/WvbXX/
Change
$("#NewBtn").on("click", function(){
to
$(document).on("click", "#NewBtn", function(){
The reason for this is that you're wanting to use the delegate form of .on(). This call is a little different in that it takes a "string" as the second parameter. That string is the selector for your "dynamic" element while the main selector need either be a parent container (not created dynamically) or the document itself.
jsFiddle
you are setting onclick event for newBtn on load of page for the first time but unfortunately newBtn not available that time. hence after changing the id it will not trigger onclick function for newBtn.
you can do one thing to make it work, set onclick event for newBtn inside the same function where you are changing the id like below.
$("#change").on("click", function(){
$("#submitBtn").attr("id", "NewBtn");
// set on click event for new button
$("#NewBtn").on("click", function(){
alert("Hello");
});
});
.attr() function does not have a callback and thus it cannot be checked unless you setup an interval using setInterval but the function itself executes pretty soon so you are not going to need it.
For solving the problem in hand event delegation proposed by tymeJV is the right way to do it.
I have this:
<input type="text" ID="txtMy" name="txtMy" onkeypress="initialize();"/>
And in my .js file I have:
initialize()
{
var x = $("#txtMy").val();
}
But, if I have '2' in my textbox, and then I enter 4, the value of x is still 2. How to resolve this?
Use keyup
Here is how you do that in the unobtrusive way.
HTML
<input type="text" id="txtMy" />
Script
$(function(){
$("#txtMy").keyup(function (event) {
alert($(this).val())
});
});
Working Sample : http://jsfiddle.net/VmELF/4/
If you want to bind the functionality to a text box which is being injected to the DOM after the dom load( possible by an Ajax call etc...), you may use jQuery on
$(function(){
$("body").on("keyup","#txtSearchKey",function (event) {
alert($(this).val())
});
});
Your spelling of initialize in the onkeypress does not match the declaration (inititalize).
keydown and keypress events both execute BEFORE the entered key has actually appeared in the text box. If you want to get the new value of the input after the key has appeared, use the keyup event instead.
<input type="text" ID="txtMy" name="txtMy" onkeyup="initialize();"/>
initialize()
{
var x = $("#txtMy").val();
}
You should consider binding your event handlers in javascript using .on(), since you're using the library anyways. Keeping your logic (javascript) seperated from your view (html) is a good habit to get in to.
instead of markup event handler you can use jquery:
var x;
$("#txtMy").on("keyup", function(){
x = $(this).val();
alert(x);
})
A few things:
Use the keyup event. keypress is firing before the character is recorded.
Your initialize() function is misspelled in your HTML snippet.
See the working jsfiddle at http://jsfiddle.net/8XTLW/1/
I have some code which loads some html from another file, which works as it should. But I am struggling to access elements from this newly loaded data.
I have this code:
var widgetSettings = $("<div>").addClass("widgetsettings").load('dashboard/chart-settings-form.php #editChartForm');
widgetSettings.appendTo(widget.element);
//so far so good...
widget.element.find('.date').each(function(i){
$(this).datetimepicker(); //this doesn't work
console.log('testing... '+$(this).attr('id')); //this doesn't even work...
});
I'd expect it to find these text boxes in the '#editChartForm' form loaded from the above url (they're within a table):
<input type="text" name="datefrom" id="datefrom" class="date" /> To: <input type="text" name="dateto" id="dateto" class="date" />
The html is definitely being loaded. Just really confused as to why I can't access any elements from the load() event.
I also wanted to apply a click function to a cancel button on the same form, and I found the only way to make it work was to put it within a 'live' function before the load:
$('.cancel').live('click', function() {
//actions here...
});
Any ideas what is going on?
Simple! Because the load() method is asynchronous, and your line widget.element.find('.date') is firing BEFORE there's actually any elements in the DOM that match it! Just use a callback in your load(), like this:
$("<div>").addClass("widgetsettings").load('dashboard/chart-settings-form.php #editChartForm', function() {
$('div.widgetsettings').find('.date').each(function(i){
$(this).datetimepicker();
console.log('testing... '+$(this).attr('id'));
});
});
$("div").load("url here",function(){
callbacks();
});
function callbacks(){
//put everything that you want to run after the load in here.
//also if the click function is in here it wont need the .live call
}
Edit: Also with the latest version of jQuery you can now use .on instead of .live (its much more efficient) ie.
$(".widgetsettings").on("click",".cancel",function(){
//actions here
});
hope this helps :)