Develop Reference

How to handle event delegation with priorities?

I have this look-a-like code in my app :
let item;
$('.parent').on('click', function () {
item = $(this).attr('item') || 0;
});
$('.parent').on('click', '.children', this, function () {
doSomething();
});
<div class="parent" item="50">
<div class="children">
</div>
</div>
<div class="parent" item="51">
<div class="children">
</div>
</div>
<div class="parent" item="52">
<div class="children">
</div>
</div>
I have a parent element with several children in it. Clicking anywhere on the parent element will give me an item information, so I will be able to load functions according to this item variable on click on children.
My problem is : I have to delegate the onClick event on children to parent element otherwise the events will trigger in this order :
Click on any child
Click on parent, which is too late because I need item variable first
I have a functionality that replaces the parent element if activated, since it was dynamically inserted into the DOM, I have to delegate the onClick event as well, like this :
$('.grandParent').on('click', '.parent', function () {
item = $(this).attr('item') || 0;
});
Now my problem is that the events are triggering in the wrong order again :
Click on any child
Click on parent
How can I manage to set click event on parent as top priority?
Edit :
I will be more specific. I have a messages list on my page, each .message element contains the message content but also some functionnalities like edit, delete, set as favorite, like, etc.
Like this :
<div class="message" data-item="1">
<a class="edit">E</a>
<a class="delete">X</a>
<a class="favorite">Fav</a>
<a class="like">Like</a>
<div class="content">
Hello world !
</div>
</div>
<div class="message" data-item="2">
<a class="edit">E</a>
<a class="delete">X</a>
<a class="favorite">Fav</a>
<a class="like">Like</a>
<div class="content">
Hello world !
</div>
</div>
Each one of those functionnalities will trigger different functions when clicked : edit(), delete(), like(), etc.
All of them will make AJAX requests which will then send the item variable to my server in order to know what item has to be impacted by this click.
To avoid repetition in my events handlers, I am trying to get the data-item attribute's value with one event bound to click on .message element, relying on the bubbling of children elements.

Get the item where you actually want it and get rid of the handler on parent:
$('.parent').on('click', '.children', function () {
item = $(this).closest('.parent').attr('item');
doSomething();
});
EDIT:
Then get the item when you click on the grandparent:
$('.grandParent').on('click', '.children', function () {
item = $(this).closest('.parent').attr('item');
});
EDIT #2:
Based on the OPs updated requirements, do it like this:
<div class="message" data-item="1">
<a class="action edit" data-type="edit">E</a>
<a class="action delete" data-type="delete">X</a>
<a class="action favorite" data-type="favorite">Fav</a>
<a class="like">Like</a>
<div class="content">
Hello world !
</div>
</div>
<div class="message" data-item="2">
<a class="action edit" data-type="edit">E</a>
<a class="action delete" data-type="delete">X</a>
<a class="action favorite" data-type="favorite">Fav</a>
<a class="like">Like</a>
<div class="content">
Hello world !
</div>
</div>
$(document).on('click','.message .action',function(e) {
const item = $(this).closest('message').attr('item');
switch($(this).data('type')) {
case 'edit': doEdit(item); break;
case 'delete': doDelete(item); break;
case 'favorite': doFavorite(item); break;
}
});
See, one event handler?
It's a very common pattern to do what you're doing. In the absence of a more robust framework (e.g. React), then using plain jQuery this is how it should be done.

I have a 100 button, click each button to display its corresponding bomb box, With javascript and angular

a button corresponding to a prompt box,each box is different shells;Although implements the desired function, but my code is too complicated, and that there is no simple way. how can I do? This is my code
<--html button-->
button1
button2
...
button100
<--html pop box-->
<div class="note1" style="display:none;">
<img class="title-css" src="note1.png">
<p class="one">note1</p>
</div>
...
<div class="note100" style="display:none;">
<img class="title-css" src="note100.png">
<p class="one">note100</p>
</div>
<--angular js-->
$scope.showRulePop = function(index) {
for(var i=1;i<=8;i++) {
$('.note'+i).hide();
}
$('.note'+index).show();
};

Well first of all, don't use jQuery, unless your in the directive level of angular jQuery have nothing to do there.
First let's get rid of the links part using a simple ng-repeat :
<--html button-->
<div ng-repeat="button in buttons">
{{button.label[i]}}
</div>
// JS in the controller
$scope.buttons = [{
label:'button1'
},{label:'button2'}];
As you can see i declare in the javascript all your buttons and i just loop over it.
Now the "bombox" or whatever it is let's make it a simple template :
<div class="{{currentnote.class}}" ng-if="currentNote">
<img class="title-css" src="{{currentNote.img}}">
<p class="one">{{currentNote.content}}</p>
</div>
// and use ng-repeat for the eight first when there is no button selected
<!-- show 1 to 8 if note current note selected -->
<div ng-repeat="button in buttons1To8" ng-if="!currentNote">
<div class="{{button.note.class}}">
<img class="title-css" src="{{button.note.img}}">
<p class="one">{{button.note.content}}</p>
</div>
</div>
// JS
$scope.buttons = [{
label:'button1'
note:{class:'note1', img:'note1.png', content:'note1'//assuming no HTML or you' ll need something more
}},{label:'button2', note:{...}}, ...];
$scope.showRulePop = function(index){
$scope.currentNote = $scope.buttons[index].note;
}
$scope.buttons1To8 = $scope.buttons.slice(0, 8);//0 to 7 in fact
That's all, no need of jQuery.

in meteor how to stop functionalities to work at a time?

In meteor, I have created a cards dynamically after submitting the form. and the dynamic card contains the show and hide buttons. When I click on show option button the hidden part is showing for all the cards instead of that particular card. the problem is the card is creating dynamically so I thought that is problem .. how to make the functionality to work separately to the each card.
Here I am attaching the code:
<div id="newActionCard">
{{#each newaction}}
<div class="workflowcard">
<div class="module-card">
<div class="res-border"></div>
<div class="card-img"></div>
<div class="res-content">
<div class=" assigned-team">{{team}}</div>
<div class=" newaction-name">{{action_title}}</div><hr>
<div class="description">{{description}}</div>
<div class=" due-on">Due on:{{d_date}}</div><hr>
<div class="subcontent">
{{> actioncardsubcontent}}
</div>
<div class="reqext">
{{> requestextensioncard}}
</div>
</div>
<div class="due">
Due on:
<div>
<span class="day-stamp">THU</span><br>
<div class="date-stamp">26</div>
<div class="month-stamp">AUG
</div>
</div>
</div>
</div>
<div class="btn-box newaction">
<button type="button" class="cancelsub" >New Action</button>
<button type="submit" class="createbtnsub" >Show Options</button>
</div>
<div class="btn-box showoption">
<button type="button" class="hideoption" style="display:none">Hide Options</button>
</div>
{{/each}}
</div>
In JS I have written the hide and show functionalities in the events..now how to stop functionality to all cards at a time.
Here is my JS:
Template.workflow.events({
"click .createbtnsub" : function() {
$( ".subcontent" ).show();
$('.createbtnsub').hide();
$('.cancelsub').hide();
$('.hideoption').show();
$('.requestextension').show();
},
"click .hideoption": function(){
$('.subcontent').hide();
},
"click .hideoption": function(){
$(".subcontent").hide();
$('.cancelsub').show();
$('.createbtnsub').show();
$('.requestextension').hide();
$('.hideoption').hide();
$('.reqext').hide();
},
"click #createActionBtn": function(){
$('#createAction').hide();
$('.editw').show();
$('.hidew').show();
},
});
Template.actioncardsubcontent.rendered = function(){
this.$(".subcontent").hide();
};
Template.requestextensioncard.rendered = function(){
this.$(".reqext").hide();
};
Template.workflow.helpers({
getWorkflow: function(){
return Workflow.find();
},
user: function(){
return Meteor.users.find({});
},
getNewaction: function(){
return Newaction.find();
},
});

Please see the following and adjust the selectors as needed:
"click .showoption": function(event){
$(event.currentTarget).next('button').show();
}
This will work for selecting sibling elements, however as a tip I would recommend rewriting your template.helper that returns the cards data from the database into something more specific.
Something like dynamic classes based on index or id so your class/id names would return as follows .showoption-12kjddfse4 . Then you can just get the attribute of the current target and apply it to your js selector.
Also as kind of an explination to why all buttons were showing, is you were using the class selector, which is meant for grabbing groups of elements/nodes. This is also another reason to created more specific classnames/ids to your use case.
So in your class name you could do something like
<button class="showoption" id="{{_id}}">button</button>
<button id="hiddenoption-{{_id}}" class="hiddenoption">button</button>
Then selecting your elements would be easier as follows:
'click .showoption'(event) => {
let id = event.currentTarget.getAttribute(id);
document.getElementById('hiddenoption-'+id).style.display = 'block';
}

jQuery script works just for one button on the product catalog

I have a product catalog and I want to save on localstorage the products selected by the user.
The jquery script only gets the first product on each page on each click... it simply ignores the rest of the products, and the console prints the same object.
Here is my HTML+TWIG code
{% for products in pagination %}
<div class="product col-sm-6 col-lg-6 col-md-6 hero-feature">
<div id="{{attribute(products ,'id')}}" class="product thumbnail">
<img id="prodImage" class="img-responsive img-rounded" src="{{attribute(products ,'image')}}" style="width:150px;height:150px" >
<div class="product caption">
<h4 id="prodPrice" class="product pull-right"><b>{{ attribute (products, 'price') }}Lei</b></h4>
<h4 id="prodName" style="height:100px;width:200px;">
<a id="prodLink"
href="{{ attribute (products, 'affiliatelink') }}"
target="_blank">{{attribute ( products, 'name') }}</br></a>
</h4>
</div>
<div class="add-to-cart" class="product" >
<button id="buttonProd" class="oneButton btn btn-danger " value="Save" type="button">Adauga</button>
</div>
</div>
</div>
{% endfor %}
Here is the jquery script
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.10.1/jquery.min.js"></script>
<script type='text/javascript' defer="defer">
$(document).ready(function() {
var prodId = $('.thumbnail').attr("id");
$("#buttonProd").on("click", 'button', function(event){
event.preventDefault();
var products =
{
prodID :$('.thumbnail').attr("id"),
prodName :$('#prodName').text(),
prodPrice :$('#prodPrice').text(),
prodImage :$('#prodImage').attr('src'),
prodLink :$('#prodLink').attr('href')
};
localStorage.setItem('products-' + prodId, JSON.stringify(products));
var retrievedObject = JSON.parse(localStorage.getItem('products-' + prodId));
console.log('retrievedObject: ', retrievedObject);
});
});
</script>
How can I make the script take each product proprieties on click. Thank you in advance.

In JQuery, the assumption is made that all ID's will be unique. Since you're repeating "#buttonProd", JQuery will only select the first one to bind the action to. If you want to bind to multiple elements, you'll either have to give each button a unique ID or use some other selector to attach your jQuery functionality.
From the documentation for the ID Selector:
Calling jQuery() (or $()) with an id selector as its argument will return a jQuery object containing a collection of either zero or one DOM element.

As the other answers have eluded to you should be using a different selector. I recommend simply adding a descriptive class to each element you wish to grab data from.
<div class="products">
<div class="product">
<div class="productName">First Product</div>
<div class="productPrice">5.00</div>
</div>
<div class="product">
<div class="productName">Second Product</div>
<div class="productPrice">4.00</div>
</div>
<button id="buttonProduct">Log Product Info</button>
</div>
If you notice in the above HTML each div that contains a product's name or a product's price shares the same class productName and productPrice respectively. In addition each container class for each product has the same class as well: product.
This will allow us to utilize the JQuery class selector $(".") to iterate over each product container. We do this using the .each() function. We use the .find() function to locate productName and productPrice in each iteration of the loop.
$(document).ready(function() {
$("#buttonProduct").click(function(){
var products = [];
// Notice the dot in $(".product") that is the class selector
// the .each iterates over every element that matches the preceding selector
$(".product").each(function(){
products.push({
// The .find() selects an element inside $(this)
// that matches the parameter (either .productName or .productPrice
productName : $(this) .find('.productName').html(),
productPrice : $(this).find('.productPrice').html()
});
});
console.log(products);
});
});
For a working example of this check out this jsfiddle. (I noticed you had console.log() in your code so that's where I output the result.)

You want to save the product in localStorage on clicking of corresponding button right?
for that instead of binding click event via jquery, put it in html and move the click code to a function saveProduct()
HTML:
<button id="buttonProd" class="oneButton btn btn-danger " value="Save" type="button" onclick="saveProduct({{attribute(products ,'id')}})">Adauga</button>
JS:
function saveProduct(event, prod_id){
event.preventDefault();
var products =
{
prodID :prod_id,
prodName :$('#'+prod_id+' #prodName').text(),
prodPrice :$('#'+prod_id+' #prodPrice').text(),
prodImage :$('#'+prod_id+' #prodImage').attr('src'),
prodLink :$('#'+prod_id+' #prodLink').attr('href')
};
localStorage.setItem('products-' + prod_id, JSON.stringify(products));
var retrievedObject = JSON.parse(localStorage.getItem('products-' + prod_id));
console.log('retrievedObject: ', retrievedObject);
});
}

You need to change #buttonProd from an id to a class. An id is only supposed to appear once on a page, so jQuery will only apply it to one. Change it to a class in your markup and your script and it should work fine. Same for prodName, prodPrice, prodImage, and prodLink. Anything that will be going inside the loop needs to be a class, and any id should be unique, like you have {{attribute(products ,'id')}}

how to change values in a hidden chunk of html code

I have this hidden block of code that i want to call based on the values that are received from server:
<div id="hiddenChart" style="display:none;">
<li style="height:auto;">
<div class="col-sm-4" id="chart_0_0">
<div class="panel panel-success" style="width:550px; height:auto;" id="accordion_0_0">
<div class="panel-heading">
<div class="btn-group" style="float:right;">
<i class="glyphicon glyphicon-minus" id="minimize_0_0"></i>
<i class="glyphicon glyphicon-remove" id="close_0_0"></i>
</div>
<h3 class="panel-title">title</h3>
</div>
<div class="panel-body" style="height:400px;">
<nvd3-multi-bar-chart data="Sec1Graf1Data" id="dataChart_0_0" height="400" showXAxis="true" reduceXTicks="true" showYAxis="true" showLegend="true" showControls="true" tooltips="true">
<svg></svg>
</nvd3-multi-bar-chart>
</div>
</div>
</div>
</li>
</div>
but i need to change some values: ids, tags, data variables.
I know how to show the code using "$('ul').append($('div').html());" but i have to change it before doing it.
How can i do it?
How do i define in which fields i have to insert the string i'me receiving?
Thk
UPDATE:
I was able put it to work, here is the fiddle with it fiddle.
When i inspect the element, the ids that i want to change, instead of #1, it returns chart_0_0.
Thank you all for your posts and help

You can get a reference to your div like this:
var $div = $('#hiddenChart');
To clone it,
var $clonedDiv = $div.clone();
Then, in the $cloneDiv object, you make the changes:
$clonedDiv.find(--selector of a node--).attr(atributeName, atributeValue); //change/add attribute
$clonedDiv.find(--selector of a node--).removeAttr(atributeName); //remove attribute
And so on. I won't explain how jQuery works, Lekhnath gave you a link.
Finally you insert the $clonedDiv with .appendTo() wherever you want. The original div remains untouched so you can clone it again and again.

Jquery Change text/html from a hidden div content :
Simple
maintain a copy of the hidden content
replace the content based on the element class/id selector with the server response
then paste the html into another div
replace the content of the hidden back to original (optional)
http://jsfiddle.net/austinnoronha/ZJ3Nt/
$(document).ready(function(){
var serverRes = {
title: "New Title In Header",
body: "New body text from server <\/br><nvd3-multi-bar-chart data=\"Sec1Graf1Data\" id=\"dataChart_0_0\" height=\"400\" showXAxis=\"true\" reduceXTicks=\"true\" showYAxis=\"true\" showLegend=\"true\" showControls=\"true\" tooltips=\"true\"><svg><\/svg><\/nvd3-multi-bar-chart>"
};
var tmpOldCont = $("#hiddenChart").html();
var counter = 1;
$(".serverres").click(function(){
$("#hiddenChart").find(".panel-body").html(counter + " = " + serverRes.body);
$("#hiddenChart").find(".panel-title").text(serverRes.title + " " + counter);
counter++;
$(".box-container").html($("#hiddenChart").html());
$("#hiddenChart").html(tmpOldCont);
});
});