How do I use a Dojo tap.hold gesture - javascript

I need to have a Javascript press and hold (long-press) event attached to a dom element. The example on Dojo's site (https://dojotoolkit.org/reference-guide/1.9/dojox/gesture.html#dojox-gesture) doesn't work at all, and I haven't found any working example.
define(["dojo/on", "dojox/gesture/tap"], function(on, tap){
var node = document.getElementById("box");
on(node, tap.hold, function(e){ alert('held') });
});
Associated fiddle: http://jsfiddle.net/L8Tp6/1/
I don't mind doing this in straight Javascript, if the Dojo option doesn't work out, but I'd like to know if I'm doing something wrong.

The problem is not the gesture or the event, but you using define(). define() should only be used when defining modules (as the name explains). When you load such a file, it will actually don't do anything. It won't load the modules and it won't execute the callbacks. The only way to make the callback run is when you call it from a require().
Your main Dojo file should always use require(). So to your code: replace define() with require() and it will work like a charm.
Code:
require(["dojo/on", "dojox/gesture/tap"], function(on, tap){
var node = document.getElementById("box");
on(node, tap.hold, function(e){ alert('held') });
});
I also updated your JSFiddle.

To Detect hold end:
on(node, tap.hold, function(e){
e.target.ontouchend = function(){
console.log('You quit holding');
}
});

Related

Something blocks addEventListener(type, handler) to work in DOM

I'm learning Vanilla JS and DOM, and I'm testing some codes in console. I have a question.
Step 1) Navigate to website "http://rehub.wpsoul.com" in chrome.
Step 2) Open a console.
Step 3) Write down below code in console.
var neww = window.open('/')
neww.addEventListener('click', function() {
alert('hi');
})
This code is not working. However, if I change the event type from 'click' to 'scroll', it does work well.
What makes it hinder to work in DOM?
Whenever I tested this code, some websites does not work event type, 'load' like this website.
I've had a headache for this for a few days. I would like to know the reason and principle of DOM and JS.
I need your help, thanks! :)
As you are opening a new window and its DOM is not yet available or ready, the event is not getting bind. Please try following code:
var neww = window.open('/')
neww.addEventListener('load', function() {
neww.document.body.addEventListener('click', function() {
alert('hi');
});
});

Meteor won't run jQuery code

I'm trying to run a block of jQuery code that shows and hides a form, but can't find a way to get Meteor to run the code on the client side. Here's the code I'm attempting to use at the moment:
if (Meteor.isClient) {
Template.post.onRendered(function(){
$(document).ready(function(){
$('.replybtn').click(function(){
if( $(this).parent().next().css('display') === 'none' ){
$(this).parent().next().css('display', 'block');
} else {
$(this).parent().next().css('display', 'none');
}
});
});
});
}
I've also tried putting the code in a script tag, which did not work. Strangely, the jQuery portion of the code alone works fine when pasted into the browser console - meaning the bug is likely in how I'm running the code in Meteor, not the jQuery itself. Also, I've confirmed that the template name is correct and can't think of any other issues that could be causing this. Any ideas on why the jQuery code may not be running?
This is probably not the best solution, but it appears that this issue can be fixed by defining a function that creates the event listener and then setting a 2 second timeout to run the function with setTimeout().
You're trying to apply a traditional jQuery pattern when Meteor provides a simple facility to attach event handlers to templates. Here would be the meteoric way:
if (Meteor.isClient) {
Template.post.events({
'.replybtn click'(e){
const selector = e.target.parentElement.nextSibling;
selector.css('display', selector.css('display') === 'none'? 'block' : 'none');
}
});
});

Why does DOM appendChild() fire on('load', ...) but jQuery append() does not?

I have the following to snippets of code:
$(document).ready(function() {
document.head.appendChild(
$('<script />').attr('src', 'source.js').on('load', function() {
...
})[0]
);
});
This will fire the load handler.
Whereas using the normal jQuery append():
$(document).ready(function() {
$('head').append(
$('<script />').attr('src', 'source.js').on('load', function() {
...
})
);
});
This will not fire the load hander.
What am I missing: why does jQuery append() not work?
Is using document.head.appendChild() a bad idea?
NOTE: I can't use $.getScript(). The code will run on a local file system and chrome throws cross site script errors.
Update
Some people had trouble reading the compact style, so I used extra line feeds to clarify which objects where calling which methods. I also made it explicit that my code is inside a $(document).ready block.
Solution
In the end I went with:
$(document).ready(function() {
$('head')[0].appendChild(
$('<script />').attr('src', 'source.js').on('load', function() {
…
})[0]
);
});
I think #istos was right in that something in domManip is breaking load.
jQuery is doing some funny business in its DOM manipulation code. If you look at jQuery's source, you'll see that it uses a method called domManip() inside the append() method.
This domManip() method creates a document fragment (it looks like the node is first appended to a "safe" fragment) and has a lot of checks and conditions regarding scripts. I'm not sure why it uses a document fragment or why all the checks about scripts exist but using the native appendChild() instead of jQuery's append() method fires the event successfully. Here is the code:
Live JSBin: http://jsbin.com/qubuyariba/1/edit
var url = 'http://d3js.org/d3.v3.min.js';
var s = document.createElement('script');
s.src = url;
s.async = true;
$(s).on('load', function(e) {
console.log(!!window.d3); // d3 exists
$(document.body).append('<h1>Load fired!</h1>');
});
$('head').get(0).appendChild(s);
Update:
appendChild() is a well supported method and there is absolutely no reason not to use it in this case.
Maybe the problem is when you choose DOM appendChild, actually you called the function is document.on('load',function(){});, however when you choose jQuery append(), your code is $('head').on('load', function(){}).
The document and head are different.
You can type the code below:
$(document).find('head').append($('<script />').attr('src', 'source.js').end().on('load', function() {
...
}));
You should probably make sure that the jquery append is fired when the document is ready. It could be that head is not actually in the dom when the append fires.
you don't have to ditch jquery completely, you could use zeptojs. Secondly, I couldn't find out how and why exactly this behavior is happening. Even though i felt answer was to be found in links below. So far i can tell that if you insert element before definig src element then load won't fire.
But for manual insertion it doesn't matter. (????)
However, what i was able to discover is that if you use appendTo it works.
Code :http://jsfiddle.net/techsin/tngxnkk7/
var $ele = $('<script />').attr('src', link).load(function(){ abc(); }) ).appendTo('head');
New Info: As is understood adding script tag to dom with src attribute on it, initiates the download process of script mentioned in src. Manual insertion causes page to load external script, using append or appendTo causes jquery to initiate downloading of external js file. But event is attached using jquery and jquery initiates download then event won't fire. But if it's the page itself initiates the download then it does. Even if event is added manually, without jquery, adding via jquery to dom won't make it fire.
Links in which i think should be the answer...
Append Vs AppendChild JQuery
http://www.blog.highub.com/javascript/decoding-jquery-dommanip-dom-manipulation/
http://www.blog.highub.com/javascript/decoding-jquery-dommanip-dom-manipulation/
https://github.com/jquery/jquery/blob/master/src/manipulation.js#L477-523
http://ejohn.org/blog/dom-documentfragments/

How to remove an event out of content script scope?

I'm trying to unbind an event from a specific element and upon research, I found this. Which is useful. In itself. I didn't know you could do that. But:
Is there a way to make it work in a browser/Chrome extension? I'm talking about content scripts.
The reason why this doesn't work the way it's described there is that the website which has attached the event in question with its own script is using a different jQuery object than the one in my extension's includes/ folder. And I can try to search the event via jQuery._data(el, 'click'); but that is my jQuery object, not the one of the website where the events are apparently stored. I'm glad I figured that out after hours of fiddling around.
Or maybe it is possible to access the website's jQuery object itself?
EDIT:
What I'm ultimately trying to achieve works in theory but … it's complicated. The original script uses a plugin event and keeps reinstalling it with .on('mouseleave',….
Anyway, this is what I got thanks to you, pdoherty926:
var $el = $('div.slideshow');
$('h2', $el).click(function(){ console.log('ouch!'); }); // test event
var $slides = $('.slides', $el).detach();
$copy = $el.clone(false);
$slides.prependTo($copy);
$el.replaceWith($copy);
The test event doesn't get triggered but the event I'm actually trying to remove still fires. I can imagine figuring it out, though, now that I got closer to my goal.
Okay, the aforementioned re-installation on mouseleave really messed up this otherwise satisfying suggestion. (The site is using the jQuery Timer plug-in by Cyntaxtech). So here's how I solved it instead: I simply changed the class name (-.-' )
Now the re-installation code cannot find the element anymore.
This is how my finished script looks like:
function stop_happening() {
var $el = $('div.fullwall div.slideshow');
$el
// first, stop the current automation.
.timer('stop') // Timer plug-in
// next, change class name in order to prevent the timer
// from being started again.
.removeClass('slideshow').addClass('slideshow-disabled-automation');
//--- copied some extra code from the website itself for the onclick
// events which are supposed to keep working. I wish I could do *that*
// programmatically but I'm glad I got as far as I got. ---//
// […]
}

javascript/jquery code not working - limit to how many calls can be made in a page?

Here is the code I am using from jquery ui tabs:
<script>
$(function(){
// Tabs
$('#tabs1').tabs();
$('#tabs2').tabs();
$('#tabs3').tabs();
//hover states on the static widgets
$('#dialog_link, ul#icons li').hover(function(){
$(this).addClass('ui-state-hover');
},function() {
$(this).removeClass('ui-state-hover');
});
});
</script>
In this page: http://sekhu.net/charlie/index.php
Now Most of the jquery calls work, but this one in particular only works depending on where I place it amongst the other init. I'm using Sudo Slider jQuery Plugin and the jquery tabs to include the tabs in the slide. Is this not possible, or have I made an error somewhere? Perhaps missing a ; or something?
I'm new to jquery/script so I have no clue what's gone wrong.
Thanks
I think the last }); should be })();
But I might be confusing it with the self-executing anonymous functions
The order you do things is often critical in JavaScript, especially if you are adding events to anchors loaded dynamically. You need to do things in this order:
retrieve data with a dynamic AJAX call
process the data and display the results which may include a list of anchors
install listeners for events like click and hover on the anchors displayed
in #2.
If you try to install the listeners before you've displayed the data, they won't listen. So don't install the listeners in a document.ready() or init() function, install them in the callback of the function that loads the dynamic data the listeners apply to. Something like this
$.get('myUrl',function(data){ // get dynamic data
var anchorList = myProcess(data); // create a menu from the dynamic data
$('#myTarget').html(anchorList); // display the menu
$('#myTarget a').hover( ... ); // *now* install the listeners
$('#myTarget a').click( ... );
});

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