Develop Reference

Touchstart firing twice on mobile

I am having some trouble with a mobile menu. At first i had my code written like this which worked fine on desktop
$('#nav-icon3').click(function(){
$(this).toggleClass('open');
});
$('.menu-item').click(function(){
$('#nav-icon3').toggleClass('open');
});
after uploading and checking on my mobile device via android chrome the click function was not working, so i tried using the touchstart.
$('#nav-icon3').on('touchstart', function(){
$(this).toggleClass('open');
});
$('.menu-item').on('click touchstart', function(){
$('#nav-icon3').toggleClass('open');
});
when touching the menu-item element, the toggle fires twice. Anyway I can prevent this from happening and let it only fire once?

I think what is going on based on your question is that your event is propagating. What you can do is the stop the event from propagating by doing something like this.
$('.menu-item').on('click touchstart', function(e) {
e.stopPropagation();
$('#nav-icon3').toggleClass('open');
});
More reference here:
https://api.jquery.com/event.stoppropagation/

Using e.preventDefault(); worked for me when I had the same issue as you.
$('#nav-icon3').on('touchstart', function(e){
e.preventDefault();
$(this).toggleClass('open');
});

.scrollTop, not working on android

I have a long page with a position:fixed link. When a user clicks this link the browser scrolls to the top.
However, this doesn't seem to work on some devices using Android 4.0, like the Galaxy Pocket+.
This is the script:
$(".jsrs-go-top").click(function () {
$("html, body").animate({ scrollTop: 0 });
});
Does anyone have a clue as to how we can solve this bug?
thx,

Try this:
$("body, html").scrollTop(0);
If need animation:
$("html, body").animate({scrollTop:0}, '500', 'swing', function() {
alert("Finished animating");
});

JQuery - Android - The 'Keyup' Event Does Not Work On Backspace In Chrome

I am wondering why the backspace/ delete button does not detect a keyup event in jQuery.
I find this odd as it is useful and should be supported. Are there any alternatives to this?
This is only happening in Android - Chrome.

You can actually fix this by attaching an event listener to the input.
var inputBox = document.getElementById('inputId');
inputBox.addEventListener(‘input’, function() {
exampleFunc();
}, false);
Cheers

jQuery.mobile popup immediately hides after showing

I have a small phonegap application with jquery mobile and backbone.
I'm trying to show popup to user by manually calling .popup() method.
Everything works fine on iOS but on android I got strange issue: popup is showing for few moments and than disappear.
Here the actual code:
var PostView = Backbone.View.extend({
events: {
'touchend .add-comment-button': 'addComment'
},
addComment: function() {
this.$(".comment-popup").popup('open', { history: false });
return false; // Stop bubbling.
}
});
I'm using history: false because this popup is actualy part of subpage.
The code looks very simple, I'm just can't understand why it can disappear, and why this happen only on android devices.
Thanks, and sorry for my bad english.

I spent hours trying to fix this problem.
Finally I ended up doing the following two things that seemed to fix the problem.
1 - Use the uncompressed jqm file. i.e jquery.mobile.1.2.0.js
2 - I was triggering the popup programatically using the 'tap' option - once changed to the 'click' option it worked.
$('.option').live('click', function() {
$('#popup-div').popup('open');
});

I spent hours trying to fix this problem.
Finally I ended up doing the following two things that seemed to fix the problem.
this code snippet may help you ->
$('#testBtn').on('tap',function(e){
console.log("button clicked");
e.preventDefault();
$('#testPOPUP').popup("open");
});
Please note i have used e.perventDefault().

I didn't feel like changing my .tap() events to the click event and I didn't have a case where I could use preventDefault()so I just added a timeout to the popup('open') line. My hoverdelay in jqm is set to 150 so I set this timeout to 600 just to be on the safe side. Works fine, doesn't feel sluggish for the user.

One way to 'fix' it is by setting data-history="false" on the popup div
See also this question
JQuery Mobile popup with history=false autocloses

I have the exact same problem when trying to use popup('open') on an android 2.3 device (both in native browser and in firefox) and it works just fine on browsers on other devices. I'm also using backbone event management to open my popup (used the tap event and no aditionnal options to popup).
What I did to 'correct' the problem is that I removed the backbone event management for this event and added a listener in the render function. In your case this would look something like this :
events: {
// 'touchend .add-comment-button': 'addComment'
},
render: function() {
$(this.el).html(this.template(this.model));
$(this.el).find('.add-comment-button').tap(function(el){
this.addComment(el);
return false;
}.bind(this));
}
I have no idea where the problem comes from (must be some incompatibility between backbone and jquery mobile) and why we only see it on android but for the moment with this workaround my app seems to work fine on any device.
Edit: oops, it turns out that in my case the problem was I was missing "return false;" in the function dealing with the event.
Now that I added it, it works correctly with the backbone event management.
Sadly that doesn't explain why you have the issue and why I was seeing it only on android.

In case it helps anyone, I had the same problem occurring with Bing Maps, with the Microsoft.Maps.Events.addHandler(pin, 'click', callback) method.
Not particularly nice, but instead I stored an ID in pushpin._id and did the following:
$("#page").on('vclick', function (event) {
if (event.target.parentElement.className === "MapPushpinBase") {
$("#stopPopup").popup('open');
}
});

One brute force option is to check whether popup was hidden and reopen it.
In a loop, because the exact time the popup becomes hidden seems to be varied.
var hidden = $('#' + id + '-popup') .hasClass ('ui-popup-hidden')
if (hidden) $('#' + id) .popup ('open')
A working example: http://jsfiddle.net/ArtemGr/hgbdv9s7/
Another option could be to bind to popupafterclose:
var reopener = function() {$('#' + id) .popup ('open')}
$('#' + id) .on ('popupafterclose', reopener)
$('#' + id) .popup ('open')
Like here: http://jsfiddle.net/ArtemGr/gmpczrdm/
But for some reason the popupafterclose binding fails to fire on iPhone 4 half of the time.

Prevent scrolling in Android browser

Is there a way to prevent scrolling of a rendered HTML page in the Android browser? The following does not appear to have any impact on page scrolling in the Android browser:
var preventDefault = function(e) {
e.preventDefault();
return false;
};
document.addEventListener('touchmove',preventDefault,false);
document.body.addEventListener('touchmove',preventDefault,true);
window.addEventListener('touchmove',preventDefault,true);
(I've tried with bubbling on and off.)
It looks to me like Android Webkit makes the "window" the same length as the document, so scrolling is being done on the browser itself, not on the document body or DOM window object. What's weird is that that's exactly what webkit on iOS does, but the code above still works.

Answering my own question.
The problem ended up being that you need to capture and suppress ontouchstart as well as ontouchmove on document to stop the browser from scrolling. This is definitely different in iOS, but it still works identically on both platforms.
The actual code I ended up using looks sort of like this:
var preventDefault = function(e){
e.preventDefault();
};
var touchstart = function(e) {
document.addEventListener('touchstart', preventDefault,false);
document.addEventListener('touchmove', preventDefault,false);
/*do other stuff*/
};
var touchend = function(e) {
document.removeEventListener('touchstart', preventDefault,false);
document.removeEventListener('touchmove', preventDefault,false);
};
element.addEventListener('touchstart', touchstart, false);
element.addEventListener('touchend', touchend, false);

Not works on Chrome on Android though
But preventing event on window and stopping immediate propagation helps!
Handler should be not passive to do that.
MAY BE adding an event handler on capturing phase would help too
But this snippet below is tested by me
window.addEventListener("touchmove", function(event) {
event.preventDefault();
event.stopImmediatePropagation();
}, { passive: false });
DEMO https://codepen.io/ColCh/full/qvLqoe