I used to be able to get hold of
$('[data-role=header]').first().height()
in alpha with jQuery 1.5.2, but no longer can in beta with jQuery 1.6.1. Has something changed?
Full code - this writes 0 to console.log...
<!DOCTYPE html>
<html>
<head>
<title>Page Title</title>
<meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"/>
<link rel="stylesheet" href="http://code.jquery.com/mobile/1.0b1/jquery.mobile-1.0b1.min.css" />
<script type="text/javascript" src="http://code.jquery.com/jquery-1.6.1.min.js"></script>
<script type="text/javascript"
src="http://code.jquery.com/mobile/1.0b1/jquery.mobile-1.0b1.min.js"></script>
<script type="text/javascript">
$(document).ready(function() {
console.log($('[data-role=header]').first().height());
});
</script>
</head>
<body>
<div data-role="page" id="home">
<div data-role="header">
<h1>Header</h1>
</div>
<div data-role="content">
//lots of code
</div>
</div>
</body>
</html>
However, change this to jQuery 1.5.2 and jQuery Mobile alpha:
<script type="text/javascript" src="http://code.jquery.com/jquery-1.5.2.min.js"></script>
<script type="text/javascript" src="http://code.jquery.com/mobile/1.0a4/jquery.mobile-1.0a4.min.js"></script>
and it writes the non-zero height of the header div.
Incidentally, it is also non-zero with jQuery 1.6.1 but without jQuery Mobile. So it's something to do with the jQuery Mobile rendering.
Can't see anything in the release notes to suggest what might have happened, but I'm no jQuery expert.
The change that is causing the difference is "Responsive design helper classes: Now deprecated"
We include a set of responsive design helper classes designed to make it easy to build a responsive design that adapts the layout for various screen widths. At the time, we went with a system of dynamically appended min- and max-width classes on the body that are updated on load, resize and orientation change events as a workaround for the limitation that Internet Explorer doesn’t support media queries.
Basically, the page is getting min-height set to the current page height in the beta which is overriding the .landscape { min-height: 300px; } in the alpha.
It looks like you need to use CSS Media Queries if you want a page layout that changes or you could just add CSS style="height:43px" on the the header if you need a fixed height.
Seems like the page is not ready when you query the height(). There is no document.ready for jQuery.mobile. It doesn't explain why there is a difference between alpha and beta, but I guess a code path changed that exposed the issue.
Wrapping the query in a different event, returns the height as expected.
$("div:jqmData(role='page')").live('pageshow',function(){
console.log($('[data-role=header]').first().height());
});
I found this by examining the offsetHeight of the DOM element in the Chrome console which was non-zero but, as you reported, the height() was always reporting 0. I then created an link when clicked output the height and it was non-zero. I then realised that the height() was being called before the page was fully ready.
Relevant - jQuery mobile $(document).ready equivalent
Looks like they did change some of the syntax, Docs:
http://jquerymobile.com/demos/1.0b1/docs/api/methods.html
When finding elements by their jQuery
Mobile data attribute, please use the
custom selector :jqmData(), as it
automatically incorporates namespaced
data attributes into the lookup when
they are in use. For example, instead
of calling $("div[data-role='page']"),
you should use
$("div:jqmData(role='page')"), which
internally maps to $("div[data-"+
$.mobile.ns +"role='page']") without
forcing you to concatenate a namespace
into your selectors manually.
Try this:
$("div:jqmData(role='header')").first().height()
Related
I'm using jquery to remove a div to make my home screen look different on small screens and it's working fine on a Macbook Air and Iphone X. However on Android the div isn't removed and replaced as intended. This is the address for the website draft:
http://projetocc.learningtodom.com/
This is the code for the jquery bit:
<script>
$(function(){
if (window.matchMedia("(max-width: 750px)").matches) {
$('.desktop').remove();
}
});
$(function(){
if (window.matchMedia("(min-width: 750px)").matches) {
$('.mobiles').remove();
}
});
</script>
Let me know if you need me to post some css code as well.
If you don't have any success with your javascript approach, maybe you could consider using CSS and media queries. You may find that it's easier and gives more consistent results.
Simply add a viewport meta tag in the head of your document
<head>
...
<meta name="viewport" content="width=device-width, initial-scale=1.0">
...
</head>
And then in your CSS add the following
#media(max-width:750px){
.desktop{
display:none;
}
}
#media(min-width:751px){
.mobiles{
display:none;
}
}
I made a minor change to one of your breakpoints. With the code you had posted, both the mobile and desktop divs would be hidden at 750px.
I hope this helps!
I'm trying out iScroll and following the documentation, but for some reason I can't get it to initialize. At least, I don't think I can. From the demos and code, I'm not exactly sure what I should expect it to look like!
I've got this code:
<html>
<head>
<meta name="viewport" content="width=device-width" />
<title>Index</title>
<script src="~/Scripts/iScroll/iscroll.js"></script>
<script type="text/javascript">
var myScroll;
function loaded() {
myScroll = new IScroll('#scroll', {
mouseWheel: true,
scrollbars: true
});
}
</script>
</head>
<body onload="loaded()">
<div id="scroll">
<div>...Lots of Lorem Ipsum text here...</div>
</div>
</body>
</html>
For the sake of tidiness, I've not included the actual text I've got in the div I want to scroll, but all I've got is lots and lots of text - enough to make the page need to scroll. The reference to the iScroll file is definitely correct, even with its mixed cases.
I added in the options (mouseWheel and scrollbars) just to try and make something happen so that I could determine whether the script was being initialized. Setting scrollbars to false doesn't seem to make any difference. Bizarrely, if I set mouseWheel to false my mousewheel works, but if I set it to true it doesn't - exactly the opposite of the documentation.
I'm clearly doing something wrong, but I can't see what - it doesn't get more basic than what I'm trying. I looked at the barebone example from the documentation, but that doesn't seem to work for me either, in that there are no scrollbars displayed anywhere. I'm getting the same behaviour in Chrome (48) and IE11.
I am trying to build a simple webpage that replaces the contents of the <div id="body"> with something new based on the user clicking on a "link"
The following code does exactly what I expect in Chrome and Firefox, but does nothing (except turn the link to the visited color) in IE 10 or 11:
<!DOCTYPE html>
<html>
<head>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.4/jquery.min.js"></script>
<script>
$(document).ready(function(){
$("#activities").click(function(){
$("#body").load("test02.html");
});
});
</script>
</head>
<body>
<div id="header">
Activities
<!-- this stays the same -->
</div>
<div id="body">
<p>this is the content that arrives without needing prompting</p>
<!-- All content will be loaded here dynamically -->
</div>
<div id="footer">
<!-- this stays the same -->
</div>
</body>
</html>
This is the content of "test02.html":
<p>---</p>
<p>Hello world!</p>
<p>---</p>
I've checked the javascript security settings in IE and everything is set to "enable." I've also tried adding type="text/javascript" to the script tags.
Some amount of Googling has turned up the possible need to reinstall IE, which I have tried.
Anyone have an idea about how to get this working in IE?
The problem is that IE breaks itself in "compatibility" mode. The way in which it breaks itself in this case is failing to correctly look up your div id="body" element. I think that was observation error on my part, I think the real problem is addEventListener (because jQuery 2.x doesn't fall back to attachEvent anymore, since it doesn't support IE8 and earlier [or the "compatibility" modes that act like them]):
I can replicate the problem. The problem goes away if I tell IE not to break itself (e.g., not to use compatibility mode) by adding this to the top of the head element:
<meta http-equiv="X-UA-Compatible" content="IE=Edge" />
IE's default for intranet sites is to display them in "compatibility" mode.
At one point I wasn't at all sure that when in "compatibility" mode it didn't get confused about that element with the id "body". IE has a history of getting confused by things like that. So you might also consider the-body or similar, but I tested and didn't seem to need it.
Side note: You probably also want to add a return false or e.preventDefault() to your click handler, so it doesn't follow the # link (which will scroll back to the top of the page and add # to the address bar).
add meta tag below to your page
<meta http-equiv="X-UA-Compatible" content="IE=edge;chrome=1" />
Do you mean <body> tag or <div id="body"> and do you ever try preventing default behavior of the link by using this below code :
$(document).ready(function(){
$("#activities").click(function( e ){
e.preventDefault(); //<---- add here
$("#body").load("test02.html");
});
});
To elaborate more on my question, I designed a website specifically to be viewed on a desktop. It does not look good if being tested on a mobile device. Therefore, I made a complete different layout for my website (containing all of the same content) by using jQuery mobile (due to its simplicity).
I realize now that there were probably better ways in doing this, such as implementing the mobile view in my CSS file, based on media queries, but this is the way that I chose to do it and would prefer to stick with it.
So here's my problem:
I want to use my JavaScript file to detect the different screen sizes, in order to display the desktop view or mobile view, based on their specified screen width and height. As of now, my desktop view and mobile view are in two different html files, and I know that is not good.
I don't want two html files, I want to combine the two! That's the only way I would be able to call the two different codes in my .js file, correct? Does anyone know how to do this?
In my mobile view file, I needed to include the jQuery libraries. Without those, it will not work. But when I tried including that in my desktop view file (since I am now trying to combine the files), I tested it alone with just that and it completely messed up the view on my desktop. How do I solve this?? Other than that, I'm assuming I would just separate the codes with two different 's as far as combining the rest of the code, yeah?
For example,
<div id="desktop"> ..... </div> <!-- this is for desktop view -->
and
<div id="mobile"> ..... </div> <!-- this is for mobile view -->
Please, any help would be so appreciated. I've tried researching this, but I can't find anything specific enough to answer my questions.
Here is the beginning of my desktop view file:
<!DOCTYPE html>
<html>
<head>
<link rel="stylesheet" type="text/css" href="hwk5.css">
<script type="text/javascript" src="hwk5.js"></script>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js"></script>
</head>
<body>
And here is the beginning of my mobile view file:
<head>
<meta charset="utf-8" />
<meta name="viewport" content="width=device-width, initial-scale=1 maximum-scale=1">
<link rel="stylesheet" href="http://code.jquery.com/mobile/1.4.2/jquery.mobile-1.4.2.min.css">
<script src="http://code.jquery.com/jquery-1.10.2.min.js"></script>
<script src="http://code.jquery.com/mobile/1.4.2/jquery.mobile-1.4.2.min.js"></script>
<style>
img.fullscreen {
max-height:50%;
max-width:50%;
}
</style>
</head>
<body>
As I said in my comment, you could just detect mobile browsing with PHP and redirect the user to the desktop or mobile site accordingly, but if you really want to do this with jQuery, it is possible.
You would want to check the page width onReady and onResize:
$(document).ready(function(){resize();});
$(window).resize(function(){resize();});
function resize()
{
var mobileMaxWidth = 640; //Define this to whatever size you want
if($(window).width() > mobileMaxWidth)
{
$("div#desktop").show();
$("div#mobile").hide();
}
else
{
$("div#desktop").hide();
$("div#mobile").show();
}
}
JSFiddle
As far as jQuery messing up your desktop site, you must be using another DOM. Are you importing MooTools or another popular DOM that uses $? If so, you would need to explicitly mark jQuery code as jQuery("selector")... instead of $ or use jQuery.noConflict.
For more information, see this post.
I Suggest You To Write Two Seperate CSS Files... One For Desktop And Other For Mobile. And According to the current screen size change the css files using javascript.
To achieve this You Can Use this script
<script type="text/javascript">
$(document).ready(function () {
changecss();
});
$(window).resize(function () { changecss(); });
function changecss() {
var windowwidth = $(window).width();
var windowheight = $(window).height();
if (windowwidth >= 1024 && windowheight >= 768) {
//alert('Screen size: 1024x768 or larger');
$("link[rel=stylesheet]:not(:first)").attr({ href: "Style2.css" });
}
else {
$("link[rel=stylesheet]:not(:first)").attr({ href: "Style1.css" });
}
}
</script>
HTML
<div>
The colour of this text will change.
</div>
So I was thinking a simple way to deal with javascript being disabled by the browser would be the following:
<head>
<title>JavaScript Test</title>
<noscript>
<meta http-equiv="Refresh"
content="1;url=nojs.html" />
</noscript>
</head>
And having the nojs.html have something like:
<p>Return to test after enabling javascrpt.</p>
At the crash page.
This isn't my preferred method, but it's nice and simple until something more graceful can be worked out for users without javascript.
However, it is not valid to put a <noscript> element in the head section. The preliminary tests worked anyway, of course, but I'm superstitious when it comes to my code being valid, plus I'd hate for this to actually fail a field test.
So is there a valid way to do this? Perhaps wrapping the noscript in another element, like an object tag? Or some even simpler way I'm not thinking of?
I am not sure why you need to redirect to another page instead of just showing a message. I use JS and a little CSS to handle these situations for me. Something like this:
<head>
....
<script type="text/javascript"> document.documentElement.className += " js"</script>
<link rel="stylesheet" type='text/css' href="css/layout.css" media="all" />
</head>
<body>
<div id="noscript">Please enable JavaScript, then refresh this page. JavaScript is required on this site</div>
<div id="wrapper">
...
</div>
</body>
Then in layout.css:
#wrapper { display: none } /* Hide if JS disabled */
.js #wrapper { display: block } /* Show if JS enabled */
.js #noscript { display: none } /* Hide if JS enabled */
By doing it this way, the class is applied to the html element before the page is rendered so you won't get a flicker as the non-JS content is swapped out for the JS content.
Doug's solution is pretty good, but it has a few drawbacks:
It is not valid to have a class attribute on the html element. Instead, use the body.
It requires that you know what display type to set the element to (i.e. ".js #wrapper { display: block }").
A simpler, more valid and flexible solution using the same approach could be:
<html>
<head>
<!-- put this in a separate stylesheet -->
<style type="text/css">
.jsOff .jsOnly{
display:none;
}
</style>
</head>
<body class="jsOff">
<script type="text/javascript">
document.body.className = document.body.className.replace('jsOff ','');
</script>
<noscript><p>Please enable JavaScript and then refresh the page.</p></noscript>
<p class="jsOnly">I am only shown if JS is enabled</p>
</body>
</html>
With this, it's valid html (no class attribute on the html element). It is simpler (less CSS). It's flexible. Just add the "jsOnly" class to any element that you want to only display when JS is enabled.
The <noscript> tag cannot be in the <head>, it must be in the <body>
The common practice is to show a message instead of redirecting, as there is no way to redirect only if javascript is disabled.
You could do it the other way around, have the first page be nojs.html, and on that page use javascript to redirect to the main content.
If you truly want a valid way to do it, make your main page the nojs.htm page and use JS to hide all content before it's shown to the user and immediately redirect to the real main page using javascript.
I like Doug's solution. However, if you need to redirect, I would remember that while there is a spec and a standard, the world of web browsers is a dirty, imperfect world. Whether or not something is allowed by the spec is not as important as whether or not it works in the set of browsers you care about.
Just look at the source code of any major site... Most of them won't validate I'd bet :)
What about:
noscript{
z-index:100;
position:absolute;
top:0;
left:0;
width:100%;
height:100%;
min-height:1024px; background:#FFF;
}
And:
<noscript>
<p>Please enable Javascript on your browser.</p></noscript>