how to detect div value (Django rendered) change with MutationObserver - html

I am rendering a value from django backend to frontend, and I am trying to detect the div value change with MutationObserver. Below is my current code:
MutationObserver part:
window.addEventListener('load', function () {
var element = document.getElementById('myTaskList');
var MutationObserver = window.MutationObserver || window.WebKitMutationObserver || window.MozMutationObserver;
var observer = new MutationObserver(myFunction);
observer.observe(element, {
childList: true
});
function myFunction() {
console.log("this is a trial")
console.log(element);
console.log(element.innerHTML);
}
// setTimeout(function(){
// element.innerHTML = 'Hello World!';
// }, 1000);
//
// setTimeout(function(){
// element.innerHTML = 'Hello Space!';
// }, 2000);
});
html part:
<div hidden id="myTaskList">{{resultList | safe}}</div>
I am rendering a string "dummyValue" to the div, but just don't see the value from the console.log() statements inside function.
this works well when I uncomment the setTimeout functions though.
Thanks for any help on why MutationObserver won't detect the rendered div value

I finally figured out the reason. Hope this might be helpful for people having similar issues in the future.
So, basically I was using my Django form submit button to do two actions at one time:
1. submit data to the view and process the data in the view;
2. trigger another function with the click action through
Ajax.
The second action was blocked by the first action, and I was only able to get result from action 1.
My solution: I modified action 1 to use Ajax as well. As I mentioned above, I originally used the Django form to submit data. I trigger action 2 inside the success function of action 1. Everything is working well now.

Related

How to send a single request through p:commandButton inside p:dialog? [duplicate]

I have following jQuery code to prevent double clicking a button. It works fine. I am using Page_ClientValidate() to ensure that the double click is prevented only if the page is valid. [If there are validation errors the flag should not be set as there is no postback to server started]
Is there a better method to prevent the second click on the button before the page loads back?
Can we set the flag isOperationInProgress = yesIndicator only if the page is causing a postback to server? Is there a suitable event for it that will be called before the user can click on the button for the second time?
Note: I am looking for a solution that won't require any new API
Note: This question is not a duplicate. Here I am trying to avoid the use of Page_ClientValidate(). Also I am looking for an event where I can move the code so that I need not use Page_ClientValidate()
Note: No ajax involved in my scenario. The ASP.Net form will be submitted to server synchronously. The button click event in javascript is only for preventing double click. The form submission is synchronous using ASP.Net.
Present Code
$(document).ready(function () {
var noIndicator = 'No';
var yesIndicator = 'Yes';
var isOperationInProgress = 'No';
$('.applicationButton').click(function (e) {
// Prevent button from double click
var isPageValid = Page_ClientValidate();
if (isPageValid) {
if (isOperationInProgress == noIndicator) {
isOperationInProgress = yesIndicator;
} else {
e.preventDefault();
}
}
});
});
References:
Validator causes improper behavior for double click check
Whether to use Page_IsValid or Page_ClientValidate() (for Client Side Events)
Note by #Peter Ivan in the above references:
calling Page_ClientValidate() repeatedly may cause the page to be too obtrusive (multiple alerts etc.).
I found this solution that is simple and worked for me:
<form ...>
<input ...>
<button ... onclick="this.disabled=true;this.value='Submitting...'; this.form.submit();">
</form>
This solution was found in:
Original solution
JS provides an easy solution by using the event properties:
$('selector').click(function(event) {
if(!event.detail || event.detail == 1){//activate on first click only to avoid hiding again on multiple clicks
// code here. // It will execute only once on multiple clicks
}
});
disable the button on click, enable it after the operation completes
$(document).ready(function () {
$("#btn").on("click", function() {
$(this).attr("disabled", "disabled");
doWork(); //this method contains your logic
});
});
function doWork() {
alert("doing work");
//actually this function will do something and when processing is done the button is enabled by removing the 'disabled' attribute
//I use setTimeout so you can see the button can only be clicked once, and can't be clicked again while work is being done
setTimeout('$("#btn").removeAttr("disabled")', 1500);
}
working example
I modified the solution by #Kalyani and so far it's been working beautifully!
$('selector').click(function(event) {
if(!event.detail || event.detail == 1){ return true; }
else { return false; }
});
Disable pointer events in the first line of your callback, and then resume them on the last line.
element.on('click', function() {
element.css('pointer-events', 'none');
//do all of your stuff
element.css('pointer-events', 'auto');
};
After hours of searching i fixed it in this way:
old_timestamp = null;
$('#productivity_table').on('click', function(event) {
// code executed at first load
// not working if you press too many clicks, it waits 1 second
if(old_timestamp == null || old_timestamp + 1000 < event.timeStamp)
{
// write the code / slide / fade / whatever
old_timestamp = event.timeStamp;
}
});
you can use jQuery's [one][1] :
.one( events [, data ], handler ) Returns: jQuery
Description: Attach a handler to an event for the elements. The handler is executed at most once per element per event type.
see examples:
using jQuery: https://codepen.io/loicjaouen/pen/RwweLVx
// add an even listener that will run only once
$("#click_here_button").one("click", once_callback);
using count,
clickcount++;
if (clickcount == 1) {}
After coming back again clickcount set to zero.
May be this will help and give the desired functionality :
$('#disable').on('click', function(){
$('#disable').attr("disabled", true);
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<button id="disable">Disable Me!</button>
<p>Hello</p>
We can use on and off click for preventing Multiple clicks. i tried it to my application and it's working as expected.
$(document).ready(function () {
$("#disable").on('click', function () {
$(this).off('click');
// enter code here
});
})
This should work for you:
$(document).ready(function () {
$('.applicationButton').click(function (e) {
var btn = $(this),
isPageValid = Page_ClientValidate(); // cache state of page validation
if (!isPageValid) {
// page isn't valid, block form submission
e.preventDefault();
}
// disable the button only if the page is valid.
// when the postback returns, the button will be re-enabled by default
btn.prop('disabled', isPageValid);
return isPageValid;
});
});
Please note that you should also take steps server-side to prevent double-posts as not every visitor to your site will be polite enough to visit it with a browser (let alone a JavaScript-enabled browser).
The absolute best way I've found is to immediately disable the button when clicked:
$('#myButton').click(function() {
$('#myButton').prop('disabled', true);
});
And re-enable it when needed, for example:
validation failed
error while processing the form data by the server, then after an error response using jQuery
Another way to avoid a quick double-click is to use the native JavaScript function ondblclick, but in this case it doesn't work if the submit form works through jQuery.
One way you do this is set a counter and if number exceeds the certain number return false.
easy as this.
var mybutton_counter=0;
$("#mybutton").on('click', function(e){
if (mybutton_counter>0){return false;} //you can set the number to any
//your call
mybutton_counter++; //incremental
});
make sure, if statement is on top of your call.
If you are doing a full round-trip post-back, you can just make the button disappear. If there are validation errors, the button will be visible again upon reload of the page.
First set add a style to your button:
<h:commandButton id="SaveBtn" value="Save"
styleClass="hideOnClick"
actionListener="#{someBean.saveAction()}"/>
Then make it hide when clicked.
$(document).ready(function() {
$(".hideOnClick").click(function(e) {
$(e.toElement).hide();
});
});
Just copy paste this code in your script and edit #button1 with your button id and it will resolve your issue.
<script type="text/javascript">
$(document).ready(function(){
$("#button1").submit(function() {
$(this).submit(function() {
return false;
});
return true;
});
});
</script
Plain JavaScript:
Set an attribute to the element being interacted
Remove the attribute after a timeout
If the element has the attribute, do nothing
const throttleInput = document.querySelector('button');
throttleInput.onclick = function() {
if (!throttleInput.hasAttribute('data-prevent-double-click')) {
throttleInput.setAttribute('data-prevent-double-click', true);
throttleInput.setAttribute('disabled', true);
document.body.append("Foo!");
}
setTimeout(function() {
throttleInput.removeAttribute('disabled');
throttleInput.removeAttribute('data-prevent-double-click');
}, 3000);
}
<button>Click to add "Foo"!</button>
We also set the button to .disabled=true. I added the HTML Command input with type hidden to identify if the transaction has been added by the Computer Server to the Database.
Example HTML and PHP Commands:
<button onclick="myAddFunction(<?php echo $value['patient_id'];?>)" id="addButtonId">ADD</button>
<input type="hidden" id="hasPatientInListParam" value="<?php echo $hasPatientInListParamValue;?>">
Example Javascript Command:
function myAddFunction(patientId) {
document.getElementById("addButtonId").disabled=true;
var hasPatientInList = document.getElementById("hasPatientInListParam").value;
if (hasPatientInList) {
alert("Only one (1) patient in each List.");
return;
}
window.location.href = "webAddress/addTransaction/"+patientId; //reloads page
}
After reloading the page, the computer auto-sets the button to .disabled=false. At present, these actions prevent the multiple clicks problem in our case.
I hope these help you too.
Thank you.
One way I found that works is using bootstrap css to display a modal window with a spinner on it. This way nothing in the background can be clicked. Just need to make sure that you hide the modal window again after your long process completes.
so I found a simple solution, hope this helps.
all I had to do was create a counter = 0, and make the function that runs when clicked only runnable if the counter is = 0, when someone clicks the function the first line in the function sets counter = 1 and this will prevent the user from running the function multiple times when the function is done the last line of the code inside the function sets counter to 0 again
you could use a structure like this, it will execute just once:
document.getElementById('buttonID').addEventListener('click', () => {
...Do things...
},{once:true});

How to trigger an event in Mootools for a specific tag/element with a specific element ID?

How to trigger an event in Mootools for a specific tag/element with a specific element ID?
I have this:
Video
This rel="rokbox" means that the element will be used by the Mootools RokBox modal box, but I've hidden the link.
Now, I've added this code:
window.onload = function() {
if(document.readyState == 'complete') {
// point of execution
// here I want to trigger the "a" element I've wrote up before
}
}
The code reaches until the "point of execution", when I set a basic alert, or whatsoever.
window.addEvent('domready', function() {
$('video_popup').fireEvent('click');
});
Note the use addEvent/domready, which is the proper method to add a function which must execute once the page is ready.

Why does not jQuery.live function work with static elements?

I have a dynamic HTML table, where I can add and remove rows.
Each row contains a button that has a class removeRow.
In my JavaScript, I have:
$('button.removeRow').live("click", function () {
var row = $(this).parents('tr')
row.remove();
return false;
});
The problem is that it works for all buttons that belong to rows that were inserted after the page was loaded (by clicking on 'Add row' button).
It works for existing buttons, only if I change the above code to (but then it does not work for dynamically added rows):
$('button.removeRow').click(function () {
var row = $(this).parents('tr')
row.remove();
return false;
});
I think that the live function should work for both, so can you point me into the right direction? Where can it go wrong?
OK I found a bug today. Somewhere in my code I had:
$('input[type=submit], button').click(function () {
return false;
});
I wanted it to work with the submit button, so it would not submit the form on click. I do not remember why I put button there. Anyways, because of that my static button clicks were attached this event, while dynamically created ones were not. Therefore live 'click' worked for dynamic buttons. Stupid mistake...
Hacky solution: Do both
$('button.removeRow').live("click", function () {
var row = $(this).parents('tr')
row.remove();
return false;
});
and
$('button.removeRow').click(function () {
var row = $(this).parents('tr')
row.remove();
return false;
});
It would be helpful if you posted some example HTML as well as the code responsible for inserting new rows, though.
Maybe something is going wrong if other tr elements are matched by your .parents() selector. Try .closest():
$('button.removeRow').live("click", function(){
$(this).closest('tr').remove();
return false;
});
The live should work for both dynamic and pre-rendered elements.
I'd start by working out if that content really exists before that jQuery is run...Try outputting the result of the following somewhere, or use the debugger keyword, or even the dreaded alert:
$('button.removeRow').length
// The rest of your click handler definition...

jQuery datepicker won't work on a AJAX added html element

I have a jQuery datepicker function bound to the "birthday" input html element, written in the page header:
<script type="text/javascript">
$(function() {
$( "#birthday" ).datepicker();
});
</script>
Next, I have some AJAX functionality - it adds new input html element to the page. That element is:
<input type="text" id="birthday" value="" class="detail-textbox1" />
Clicking on that birthday element does not pop up the date picker below the text field. I expected this, as the element is added after the page is loaded, thus it isn't in relation with the function provided in the header.
How can I make it work? I tried moving the script from the header to the body, but nothing seems to work. Thanks.
P.S. If I create an input html element with id="birthday" in the page body, everythig works as expected. It appears that only the elements added through AJAX are dysfunctional.
I'm a bit late to the party, but for thoroughness - and with the .live() function being deprecated from jQuery 1.7 onwards - I thought I'd provide an updated solution based on my experiences, and from all the help I got from other answers on StackOverflow!
I had a situation where I needed to add the datepicker functionality to input fields that were being added to the DOM through AJAX calls at random, and I couldn't modify the script making the AJAX calls to attach the datepicker functionality, so I opted for the new shiny .on() function with its delegation features:
// do this once the DOM's available...
$(function(){
// this line will add an event handler to the selected inputs, both
// current and future, whenever they are clicked...
// this is delegation at work, and you can use any containing element
// you like - I just used the "body" tag for convenience...
$("body").on("click", ".my_input_element", function(){
// as an added bonus, if you are afraid of attaching the "datepicker"
// multiple times, you can check for the "hasDatepicker" class...
if (!$(this).hasClass("hasDatepicker"))
{
$(this).datepicker();
$(this).datepicker("show");
}
});
});
I hope this helps someone, and thanks for all the answers so far that led me to this solution that worked for me! :)
You need to use .live() so that any newly added elements have the event handler attached: http://api.jquery.com/live/
$('#birthday').bind('load', function() {
$(this).datepicker();
});
EDIT
.live() documentation states, that it is a bit out of date. With new versions of jquery (1.7+) use .on().
Boris, JK: This was super helpful for me. I have also found that you can use the following for AJAX html if you want to use Datepicker's date range selection:
$('#groundtransporation').live('focus', function() {
var gt = $( "#rentalPickUp, #rentalDropOff" ).datepicker({
defaultDate: "+1w",
changeMonth: true,
numberOfMonths: 2,
onSelect: function( selectedDate ) {
var option = this.id == "rentalPickUp" ? "minDate" : "maxDate",
instance = $( this ).data( "datepicker" ),
date = $.datepicker.parseDate(
instance.settings.dateFormat ||
$.datepicker._defaults.dateFormat,
selectedDate, instance.settings );
gt.not( this ).datepicker( "option", option, date );
}
});
});
I got another case.
My script is copying last table elements including datepicker.
The jquery will not working because the copied element has mark that it "hasDatepicker".
To activate datepicker in new element, remove that class name and the initiate it, like this.
$("#yournewelementid").attr("class","your-class-name");
$("#yournewelementid").datepicker();
your issue is always happens when elements don't exist when you try to initialize it.
When you use $(function(){/** some code **/}); elements must exsit on the document, it means that has to be on the html so you could can create a function to initialize the component or initialize it on the success event after been add it to the document.
Is important to first add the external html load in the ajax request to the document before you try to initialize it or it won't be initialize at all.
Example:
$.ajax({
url:"ajax_html.html",
dataType:"html"
}).done(function(html){
$("#selector").html(html)
init();
});
function init(){
$(".birthday").datepicker({});
}
You could initialize the date picker for the newly added element within your ajax success callback:
$.ajax({
...
success: function(response) {
if(response.success) {
$(body).append(response.html);
$("#birthday").datepicker();
}
}
});

How to do callback + update div tag in javascript

I have an ASP.NET MVC application with pages where the content is loaded into divs from client via JavaScript/jQuery/JSON. The loaded content contains a-tags with references to a function that updates server side values, then redirects to reload of entire page even though.
I wish to replace the a-tags with 'something' to still call a server-side function, then reload the div only.
What is the 'right' way of doing this?
All comments welcome.
This is as far as I got so far. getResponseCell() returns a td-tag filled with a-tag.
I've mangled Glens suggestion into the .click() addition, but it just calls the onClickedEvent...
Code sample:
onClickedEvent=function()
{
return false;
}
getResponseCell=function(label, action, eventId)
{
tmpSubSubCell=document.createElement("td");
link = document.createElement("A");
link.appendChild( document.createTextNode( label));
link.setAttribute("href", "/EventResponse/"+ action + "/" + eventId);
//link.setAttribute("href", "#divContentsEventList");
//link.setAttribute("onclick", "onClickedEvent(); return false;");
link.setAttribute("className", "eventResponseLink");
link.click(onClickedEvent());
// link=jQuery("<A>Kommer<A/>").attr("href", "/EventResponse/"+ action + "/" + eventId).addClass("eventResponseLink");
// link.appendTo(tmpSubSubCell);
tmpSubSubCell.appendChild(link);
return tmpSubSubCell;
}
And the solution that worked for me looks like this:
onClickedEvent=function(event, actionLink)
{
event.preventDefault();
$("eventListDisplay").load(actionLink);
refreshEventList();
return false;
}
getResponseCell=function(label, action, eventId)
{
tmpSubSubCell=document.createElement("td");
link = document.createElement("A");
link.setAttribute("id",action + eventId);
link.appendChild( document.createTextNode( label));
actionLink = "/EventResponse/"+ action + "/" + eventId;
link.setAttribute("href", actionLink);
className = "eventResponseLink"+ action + eventId;
link.setAttribute("className", className);
$('a.'+className).live('click', function (event)
{
onClickedEvent(event,$(this).attr('href'));
});
tmpSubSubCell.appendChild(link);
return tmpSubSubCell;
}
Without really seeing more information.....
If you're a's are being added to the DOM after the initial page load, you cannot use the usual click() or bind() methods in jQuery; this is because these methods only bind the events to those elements that are registered in the DOM at the time the methods are called. live() on the other hand, will register the event for all current, and future elements (using the event bubbling mechanism in Javascript).
$(document).ready(function () {
$('a.eventResponseLink').live('click', function (event) {
var self = $(this);
self.closest('div').load('/callYourServerSideFunction.asp?clickedHref=' + self.attr('href'));
event.preventDefault();
});
});
We're using event.preventDefault() to prevent the default action of the a-tag being executed; e.g. reloading or changing page.
Edit: The issue won't be caused by that. That's the power of jQuery; being able to bind the same event to multiple elements. Check your HTML; maybe you're missing a closing </a> somewhere? Maybe your binding the event in a location that gets called multiple times? Each time .live() gets called, it will add ANOTHER event handler to all matched elements. It only needs to be bound once on page load.
jQuery provides loads of way for you to select the elements; check out the list. Looking at your link variable, it looks like all your links have a href starting with /EventResponse/; so you can use $('a[href^=/EventResponse/]') as the selector instead.
We need code to give you a proper answer, but the following code will catch the click of an a-tag, and reload the div that it's inside:
$(document).ready(function() {
$("a").click(function() {
//call server-side function
var parentDiv = $(this).parents("div:first");
$(parentDiv).load("getContentOfThisDiv.asp?id=" + $(parentDiv).attr("id"));
});
});
In the above code, when a link is clicked, the div that this the link is inside will be loaded with the response of the call to the asp file. The id of the div is sent to the file as a parameter.