I am trying to implement a simple notification system for a personal project, but I got stuck in how to bind events to the notifications in order to response to user actions, like accept or deny.
So far what i got is an object which is created dynamically.
/* reference to notifications */
var notifications = [];
// the notification object
var Notification = function(travelInfo){
this.el = $('#notifications_container');
this.id = Math.random().toString().substring(7);
this.travelInfo = travelInfo;
this.read = false;
};
Notification.prototype.init = function(){
this.addOne();
this.render();
this.bindFunctions();
}
/* dynamically created */
for(var i = 0; i < 10; i++){
var notification = new Notification(travelInfo);
notifications.push(notification);
notification.init();
}
This object is supposed to render and actually bind events to the rendered element in order to keep track of the actions of every notification independently:
// render the view of a notification
Notification.prototype.render = function(){
var source = $('#notification-template').html();
var template = Handlebars.compile(source);
var data = this.travelInfo;
result = template(data);
$('#notifications_container').append(result);
}
Notification.prototype.addOne = function(){
var number = +$('#notifications_indicator').html();
$('#notifications_indicator').html(number += 1);
}
Notification.prototype.removeOne = function(){
var number = +$('#notifications_indicator').html();
$('#notifications_indicator').html(number -= 1);
}
Notification.prototype.alertId= function(){
alert('the notification with id:' + this.id + ' is accepted');
}
Notification.prototype.bindFunctions = function(){
var self = this;
this.el.on('click', 'li .accept', function(){
self.alertId();
});
}
The problem with my approach is that actually if I create 10 elements the click event is triggered 10 times showing 10 alerts. What I want to know is how can I implement a system in which I render an element and also bind events to that element something like backbone's way to bind events to every view item. I feel backbone is so big for what I need right now that is just the notification system. I hope you guys could help me to find a way to do this.
If I am reading your question correctly, you are over-thinking this one a little bit.
I believe that you are looking for something like this:
<div>
<!-- This is where your HTML is -->
<button type="button" data-post-id="10">Delete this post</button>
<button type="button" data-post-id="11">Delete this post</button>
</div>
Now, on your onclick handler:
function handleDeleteClick() {
// `this` should be a reference to the element.
postId = this.getAttribute("data-post-id");
// Do something with postId
}
To complete out the code...
element.setAttribute("data-post-id", "11");
element.removeAttribute("data-post-id");
Related
I'm trying to create a chrome extension. I had a problem with the affectation of event for the new element that i append to the dom of site with content. Js
If I add an event to an element' 'for example class' exist already in the page, it works correctly. Just for my new appended element((in the code iadded a button ,the event is just an alert to test))
function tst() {
myclass = $("._3hg-._42ft");
myclass = myclass.not(".supp");
myclass.addClass("supp");
var patt = /https:\/\/(.)*\.facebook\.com\/(.)*\/(posts|photos|videos)\/(\w|\.|\d)*/g;
for (i = 0; i < myclass.length; i++) {
result = patt.exec(myclass[i]);
myclass.append('<button class="fact" id=' + result[0] + ' style="position: absolute;">fact</button>');
};
/* this is a simple event*/
/***********************/
$(".fact").on('click', function() {
alert("no event work ");
});
Making somewhat broad assumption here in my answer that it is JavaScript/jQuery related and is NOT an extension...or is so still in that context.
You need to attach the event to the container here perhaps for the dynamically created elements. Lots of global stuff, suggested to not do that, updated there.
Appends a lot of buttons perhaps? might need to only hit DOM once but left as-is in this isolated function.
function tst() {
let myclass = $("._3hg-._42ft")
.not(".supp");
myclass.addClass("supp");
//let result = {};
var patt = /https:\/\/(.)*\.facebook\.com\/(.)*\/(posts|photos|videos)\/(\w|\.|\d)*/g;
var i = 0; //avoid global
for (i; i < myclass.length; i++) {
// broad assumption of the returned value from patt.exec() here
// not even sure why it needs an id, have a class, use for css
let result = patt.exec(myclass[i]);
myclass.append('<button class="fact" id="' + result[0] + '">fact</button>');
}
/* attache event to pre-existing element */
/***********************/
myclass.on('click', ".fact", function() {
alert("event works");
});
}
button.fact {
position: absolute;
}
PLEASE READ QUESTION BEFORE READING CODE!!!
I've added a checkbox element on Dialog definition of the table dialog (it works). Now I want the checkbox to be checked by default when the table being edited has a certain class (which is usually visible on the advanced tab). According to the documentation, I should be able to do something like this in my setup function. I've tried many things and you could hopefully help me. This is my code.
CKEDITOR.on( 'dialogDefinition', function( evt )
{
var dialog = evt.data;
if(dialog.name == 'table' || dialog.name=='tableProperties')
{
// Get dialog definition.
var def = evt.data.definition;
var infoTab = def.getContents( 'info' );
infoTab.add(
{
type: 'checkbox',
id: 'myCheckBox',
label: 'Table Has Property',
setup: function()
{
//Class to look for if I successfully get the input's value
var classValueToLookFor = 'has-property';
// The current CKEditor Dialog Instance
var thisDialog = CKEDITOR.dialog.getCurrent();
// The Element whose value I want to get
var classElement = theDialog.getContentElement('advanced','advCSSClasses');
// Trying to Get Value of this class Element According to documentation
var containedClasses = theDialog.getValueOf('advanced','advCSSClasses');
// Trying to debug the value above
console.log(containedClasses); // This shows nothing
// Trying to debug InitValue which shows something according to prototype
console.log(classElement.getInitValue()); //This also shows nothing
//Checking if Element has the class I'm looking for to mark the checkbox
if(containedClasses.indexOf(classValueToLookFor) != -1)
{
//Check current checkbox since value has been found
this.setValue('checked');
}
}
onClick: function() // You can ignore this function, just put it in case you were wondering how I'm putting the has-property, might help someone else (works well) ;)
{
var checked = this.getValue();
var classValueToSet = 'has-property';
var thisDialog = CKEDITOR.dialog.getCurrent();
var containedClasses = theDialog.getValueOf('advanced','advCSSClasses');
if(checked)
{
if(containedClasses.indexOf(classValueToSet) != -1)
{
//console.log('already contains class: '+classValueToSet);
}
else
{
containedClasses += containedClasses+" "+classValueToSet;
}
}
else
{
if(containedClasses.indexOf(classValueToSet) != -1)
{
containedClasses = containedClasses.replace(classValueToSet,'');
}
else
{
//console.log('already removed class: '+classValueToSet);
}
}
thisDialog.setValueOf('advanced','advCSSClasses',containedClasses);
}
}
}
Here are some debug statements that can be helpful to add into the setup function and understand what is going on, you shouldn't need to go through all I've went through ;)
console.log('in setup function');
console.log(classElement);
console.log(classElement._);
console.log(classElement.getInitValue());
console.log(classElement.getInputElement());
var inputElement = classElement.getInputElement();
var inputElementId = inputElement.getId();
console.log($('#'+inputElementId+'.cke_dialog_ui_input_text'));
console.log(classElement.getInputElement().value);
It would be nice to test your answer before suggesting. Many of the things I've tried should work in theory, but are practically not working.
Alright, so finally after a few days of trial and error, this is what finally worked for me. Maybe it could be helpful to someone. I'm sure there should be a much cleaner way to do this. All the best to everyone.
setup: function()
{
//This current checkbox
var checkbox = this;
//the class I want to find on my table
var var classValueToLookFor = 'has-property';
//Current Dialog instance
var thisDialog = CKEDITOR.dialog.getCurrent();
//This code below gets a <td> element in the table
var startElement = thisDialog.getParentEditor().getSelection().getStartElement();
// This gets me the parent of the <td> element which is my current table instance
var parentTable = $(startElement.$.offsetParent);
//Finally check if the table has the property I'm looking for.
if(parentTable.hasClass(classValueToLookFor))
{
//Mark the checkbox
checkbox.setValue('checked');
}
}
I hope it's not a problem to post much specific code here, but I figure it will be better explained if everyone can just see it, so I will give you my code and then I will explain my problem.
My code:
function addBeGoneLinks () {
var beGoneClassElems;
var beGoneSpan;
var beGoneLink;
var beGonePrintSafe;
var spacesSpan;
//var middotSpan = document.createElement ('span');
var interactionContainer = document.getElementsByClassName('feedItemInteractionContainer');
for (var i=0; i<children.length; i++)
{
beGonePrintSafe = false;
beGoneClassElems = children[i].getElementsByClassName('beGone')
beGonePrintSafe = true;
if (beGoneClassElems.length == 0)
{
beGoneLink = document.createElement('a');
beGoneLink.href = 'javascript:void(0);';
beGoneLink.appendChild(document.createTextNode('Be Gone'));
beGoneLink.className = 'beGone';
beGoneLink.id = 'beGoneLink' + i.toString();
beGoneLink.addEventListener ("click", function() {beGone();}, false);//This line!
beGoneLink.align = 'right';
spacesSpan = document.createElement('span');
spacesSpan.innerHTML = ' - ';
if (interactionContainer[i] != undefined)
{
interactionContainer[i].appendChild(spacesSpan);
interactionContainer[i].appendChild(beGoneLink);
}
}
}
}
Here I have a function from a Greasemonkey script that I am working on. When one of the links is clicked, my aim is to have it call the function beGone() which will, among other things, remove the whole element a few parents up, thereby removing their sibling's, their parents and their parents' siblings, and one or two levels after that.
My idea was just to get the id of the link that was pressed and pass it to beGone() so that I could then get the parents using its id, but I do not know how to do that. Am I able to have the id of a link passed by the function that it calls? If not, is there any other way to do this?
I am not sure whether I am missing some really simple solution, but I haven't been able to find one rooting around the web, especially because I was unsure how I would search for this specific problem.
Try this:
beGoneLink.addEventListener("click", beGone, false);
beGone = function (evt) {
evt.target; // evt.target refers to the clicked element.
...
}
You can then use evt.target.id, evt.target.parentNode, etc.
I am working on a Phonegap app, in which I access device's contacts. I then store upto 10 contacts in window.localStorage. To do so, when the user select a button, I create a div which has three elements.
An image (contact icon that represents male/female contact)
The name of the contact
Another image (represents 'add' sign to add it to window.localStorage)
I then associate an event handler, which will first check if the contact already exists in the localStorage and then proceed to add the contact. Here is the code
function checkDuplicate(somevalue)
{
for(var i=0;i<10;i++) {
if(window.localStorage.getItem(i)!=null) {
if(window.localStorage.getItem(i)==somevalue) {
navigator.notification.alert('Entry exists at Button:'+i);
return false;
}
}
}
//chosenButton is a global variable
window.localStorage.setItem(chosenButton,somevalue);
document.getElementById('contactNumberField').textContent=somevalue;
}
//Problem is with the event listener attached to span2. Please read below
function addContact(item)
{
var parentDiv = document.getElementById('thelist');
var childDiv = document.createElement('li');
var span1 = document.createElement('span');
span1.style.float='left';
span1.innerHTML = "<img src='keypad-contact.png'/>";
var span2 = document.createElement('span');
span2.style.float='right';
span2.innerHTML="<img src='keypad-addcontact.png'/>";
span2.addEventListener('click',function({checkDuplicate(item.number);},false);
childDiv.textContent=item.name;
childDiv.style.color='white';
childDiv.appendChild(span1);
childDiv.appendChild(span2);
parentDiv.appendChild(childDiv);
}
function onSuccess(contacts)
{
var objArray = new Array();
for(var i=0; i<contacts.length;i++) {
var tempObj = new Object();
tempObj['name']=contacts[i].displayName;
tempObj['number']=contacts[i].phoneNumbers[0].value;
objArray.push(tempObj);
}
objArray.sort(
function(a,b){
var nameA = a.name.toLowerCase(),nameB=b.name.toLowerCase();
if(nameA < nameB) return -1;
else if(nameA > nameB) return 1;
return 0;
});
for(var i=0; i<objArray.length;i++) addContact(objArray[i]);
}
function onDeviceReady()
{
var options = new ContactFindOptions();
options.multiple=true;
var field = ["displayName","phoneNumbers"];
navigator.contacts.find(field, onSuccess, function(){alert('NA');}, options);
}
Problem
When I try to add a contact which is already present in window.localStorage, for my first touch on span2, I get one alert. If I try to add again by touching it for the second time, I get two alerts.. and this goes on. The trouble is with the event handler associated with span2. However, I don't know how to over come this situation. How can I ensure that irrespective of how many times I press span2, I get alert only once. How to remove the event handler as soon as it is fired?
Please help.
Fixed:
The issue was not with adding event handlers dynamically. I happen to use iScroll (cubiq) for my project and that caused the trouble. Now I am not receiving multiple alerts. The trick is to declare the globlal scroller variable only once.
var scroller = null;
and then in the function
if(!scroller) scroller = new iScroll('scrollableDiv');
I hope this could be a useful tip for people who are using iScroll and struggling with multiple alerts like me.
function init()
{
alert("init()");
/**
* Adds an event listener to onclick event on the start button.
*/
xbEvent.addEventListener(document.getElementById("viewInvitation"), "click", function()
{
new Ajax().sendRequest("31260xml/invitations.xml", null, new PageMaster());
xbEvent.addEventListener(document.getElementById("declinebutton"), "click", function ()
{
declineInvitation();
});
});
ok so what I have here is a event listerner function, the case is when viewInvitation is clicked , the program will fetch my xml file and run page master function where I created my decline button with id="declinebutton", however this does not work, the error message that i get is obj=null or the program could not find id = declinebutton, why is it so? I have created it when I called page master using dom. any help will be appreciated.
function PageMaster()
{
this.contentDiv = document.getElementById("content");
}
/**
* Builds the main part of the web page based on the given XML document object
*
* #param {Object} xmlDoc the given XML document object
*/
var subjectList;
var i;
PageMaster.prototype.doIt = function(xmlDoc)
{
alert("PageMaster()");
alert("Clear page...");
this.contentDiv.innerHTML = "";
if (null != xmlDoc)
{
alert("Build page...");
//create div Post
var divPost = document.createElement("div");
divPost.className = "post";
//create h1 element
var h1Element = document.createElement("h1");
var headingText = document.createTextNode("Invitations");
h1Element.appendChild(headingText);
//insert h1 element into div post
divPost.appendChild(h1Element);
subjectList = xmlDoc.getElementsByTagName("subject");
var groupList = xmlDoc.getElementsByTagName("group");
for (i = 0; i < subjectList.length; i++) //for each subject
{
var divEntry = document.createElement("div");
divEntry.className = "entry";
var subjectNum = subjectList[i].attributes[0].nodeValue;
var subjectName = subjectList[i].attributes[1].nodeValue;
var groupId = groupList[i].attributes[0].nodeValue;
var groupName = groupList[i].attributes[1].nodeValue;
var ownerId = groupList[i].attributes[2].nodeValue;
//set up the invitation table attributes
var table=document.createElement("table");
table.width = 411;
table.border = 3;
table.borderColor = "#990000"
var input=document.createElement("p");
var inputText=document.createTextNode("You are invited to join " + groupName + "(groupId : " + groupId +")");
input.className="style11";
var blank=document.createElement("nbps");
input.appendChild(inputText);
var acceptButton=document.createElement("input");
acceptButton.type="button";
acceptButton.id="acceptbutton";
acceptButton.value="accept";
var declineButton=document.createElement("input");
declineButton.type="button";
declineButton.id="declinebutton";
declineButton.value="decline";
table.appendChild(input);
table.appendChild(acceptButton);
table.appendChild(declineButton);
divEntry.appendChild(table);
var blankSpace = document.createElement("p");
divEntry.appendChild(blankSpace);
divPost.appendChild(divEntry);
}
//insert div post into div content
this.contentDiv.appendChild(divPost);
}
};
/**function getValueOf()
{
return i;
}**/
function declineInvitation()
{
alert("decline");
}
function acceptInvitation()
{
alert("hello");
/**var pos=getValueOf();
alert(subjectList[pos].attributes[0].nodeValue);**/
}
That's my page master function, and I definitely have created the button. but it does not work.
Try calling your function like this:
window.onload=init;
The javascript runs as the page loads. At that point, the element does not yet exist in the DOM tree. You'll need to delay the script until the page has loaded.
The example you gave doesn't create the "Decline" button, as your question suggests it should. If it should, you might want to look at that.
Of course, if the button already exists, please disregard this answer.
You have a listener inside a listener. Is that right?
What about this?:
function init(){
alert("init()");
/** * Adds an event listener to onclick event on the start button. */
xbEvent.addEventListener(document.getElementById("viewInvitation"), "click", function()
{
new Ajax().sendRequest("31260xml/invitations.xml", null, new PageMaster());
}
xbEvent.addEventListener(document.getElementById("declinebutton"), "click", function ()
{
declineInvitation();
});
As far as I understand, you create button with id="declinebutton" for each entry from xml, is that right?
If yes, I'd suggest you to generate different id's for each button (for example, append line index to 'declinebutton', so you have buttons 'declinebutton0', 'declinebutton1' an so on), and assign event listener to buttons separately in the loop.