In jqueryMobile, only the first page section seems to be loaded. When the user is redirected to a second page, the of that page is added to the first page, no headers are loaded.
If that is correct, how do we manage CSS files in jQueryMobile? Do I need to specify ALL the website classes in just one file? or is there any way to tell jquerymobile to load the css required for each page?
Thanks!
jQuery Mobile will hijax all the links on the page by default, loading the content via ajax, and only add the <body> of the response to the DOM. So, yes the easiest way is to load your required CSS up front in the first page. Bundle it and minify it to reduce the impact on the client.
Related
I have used $.mobile.changepage to do the redirect in my phonegap+jquerymobile projects. However what makes me confused is that I need to put the script of all the pages to the same file index.html. If not, the redirect page can not execute the function in its header.
for example, my index.html seem to be
$(document).bind("deviceready",function(){$.mobile.changepage("test.html");})
then, my device will redirect to test.html which seem to be
$("#btnTest").click(function(){alert("123");})
<button id="btnTest">Test</button>
However, the script will never execute in test.html. Then I put the script to index.html, what I expect to be is done. Whatever, if I put all the script to the same page, the project will become harder and harder to be preserved. Appreciated for your help.
Intro
This article can also be found HERE as a part of my blog.
How jQuery Mobile handles page changes
To understand this situation you need to understand how jQuery Mobile works. It uses ajax to load other pages.
First page is loaded normally. Its HEAD and BODY is loaded into the DOM, and they are there to await other content. When second page is loaded, only its BODY content is loaded into the DOM. To be more precise, even BODY is not fully loaded. Only first div with an attribute data-role="page" will be loaded, everything else is going to be discarded. Even if you have more pages inside a BODY only first one is going to be loaded. This rule only applies to subsequent pages, if you have more pages in an initial HTML all of them will be loaded.
That's why your button is show successfully but click event is not working. Same click event whose parent HEAD was disregarded during the page transition.
Here's an official documentation: http://jquerymobile.com/demos/1.2.0/docs/pages/page-links.html
Unfortunately you are not going to find this described in their documentation. Ether they think this is a common knowledge or they forgot to describe this like my other topics. (jQuery Mobile documentation is big but lacking many things).
Solution 1
In your second page, and every other page, move your SCRIPT tag into the BODY content, like this:
<body>
<div data-role="page">
// And rest of your HTML content
<script>
// Your javascript will go here
</script>
</div>
</body>
This is a quick solution but still an ugly one.
Working example can be found in my other answer here: Pageshow not triggered after changepage
Another working example: Page loaded differently with jQuery-mobile transition
Solution 2
Move all of your javascript into the original first HTML. Collect everything and put it inside a single js file, into a HEAD. Initialize it after jQuery Mobile has been loaded.
<head>
<meta name="viewport" content="width=device-width; initial-scale=1.0; maximum-scale=1.0; minimum-scale=1.0; user-scalable=no; target-densityDpi=device-dpi"/>
<link rel="stylesheet" href="http://code.jquery.com/mobile/1.2.0/jquery.mobile-1.2.0.min.css" />
<script src="http://code.jquery.com/mobile/1.2.0/jquery.mobile-1.2.0.min.js"></script>
<script src="index.js"></script> // Put your code into a new file
</head>
In the end I will describe why this is a part of a good solution.
Solution 3
Use rel="external" in your buttons and every elements you are using to change page. Because of it ajax is not going to be used for page loading and your jQuery Mobile app will behave like a normal web application. Unfortunately this is not a good solution in your case. Phonegap should never work as a normal web app.
Next
Official documentation, look for a chapter: Linking without Ajax
Realistic solution
Realistic solution would use Solution 2. But unlike solution 2, I would use that same index.js file and initialize it inside a HEAD of every possible other page.
Now you can ask me WHY?
Phonegap like jQuery Mobile is buggy, and sooner or later there's going to be an error and your app will fail (including loaded DOM) if your every js content is inside a single HTML file. DOM could be erased and Phonegap will refresh your current page. If that page don't have javascript that it will not work until it is restarted.
Final words
This problem can be easily fixed with a good page architecture. If anyone is interested I have wrote an ARTICLE about good jQuery Mobile page architecture. In a nut shell I am discussing that knowledge of how jQuery Mobile works is the most important thing you need to know before you can successfully create you first app.
Unlike normal ordinary HTML pages, jQuery Mobile uses ajax technology when navigating between pages. So make sure to import all your JS files and libraries in all your html pages.
If you notice closely you will see that JS files from previous page is taken into consideration when loading the second page. But if you force rrefresh the current page then the js files of the current page will be effective.
So as I said earlier make sure to import the js files in all the html files.
Also no need to call deviceready, use following syntax to call your page specific js functions
$(document).on('pageshow', '#YourPageID', function(){
// Your code goes here
});
Jquery Mobile uses ajax to load a "page". A "page" here is a div with data-role=page. If you load a physical page index.html, you can navigate using changePage to any "page" div inside that page.
However, if you want to load a "page" from other physical page, jQM will only load the first "page" div from that page. What actually happen is you do not change page, jQM just load that particular "page" div using ajax and inject it to your current page.
You have two possible architecture where you put all your "pages" in a html page and navigate from there. Or you can have multiple page architecture. You can always mix this.
To physically change page, you need to add rel=external to your link.
I've got a website that I'm converting into an app using JQM. I've read about Pages and how the DOM loads but I'm still uncertain how to architect the site.
The main page of the application is based on the Google Maps API which uses JS to load. There are 150+ target pages so I don't want them to load until the user taps the link. All of the target pages also require JS to initialize. When they return to the main page the cached state should be the default but I also need the option to run JS if the query string changes. Content doesn't change often so my preference would be to cache data once loaded but there would need to be some way to flush the cache.
I converted the site to JQM. The target page JS didn't run so I added rel='external' to the links. The JS now runs on the target but when I link back to the main page it reloads the page without running initializing the JS. The obvious solution would be to add rel="external" but then I'd be defeating all performance value. Any recommendations on how I should structure it?
Using rel=external your links will not be loaded with Ajax and you will lose animated page transitions. If you want to run some script when a page displays, use this page event:
$(document).on("pageshow", "#selector", function(event, ui) { /* your code */ });
This and other useful events are described in jQuery Mobile API Documentation.
For example, pagecreate (the now deprecated pageinit) is called once when the page initializes.
About getting query string parameters, see this answer.
I'm working on a jquery mobile project with a rails backend.
I have a "master" template, with the page structure as suggested from jQuery mobile website.
I have a multi-page system and for every page I have the same "master" template (header, footee...) and replace only the html in the <div data-role="content">.
So the header and footer are in the "master" template while the content changes for every page.
The problem is that I can't bind to any event because the page id is always the same, only the "content" div changes. This way if I subscribe to the "pagechange" event of the page, it fires for every page and I cannot apply a per-page javascript behaviour.
Do you have any suggestion on how to do this in a clean way?
Thank you,
Riccardo
I included an external javascript file on a jquery mobile page. The javascript file modifies some html and css snippet generated at the server. I've tried putting the jquery code that modifies the markup in the following jquery mobile events -
pageinit, pagecreate, pageshow, pagebeforecreate
But the script doesn't modify the loaded markup on page load, but on page refresh, it works perfectly. So I'm trying to find a way to make the modification take place before the page renders.
Any suggested will be gratefully valued.
I've solved my problem. I included all the external javascript and css files on the index page, and it worked well.
This is because jquery mobile loads subsequent pages through ajax, after loading the first page.
I have 2 application layouts: application.html.haml and application.mobile.haml. But when I switch from mobile to the non-mobile version the mobile layout is still used for the first load. In Firebug console I see that the non-mobile view was properly returned, however the browser and the Firebug HTML tab show the mobile layout. Any idea what's going? It's fine after a refresh.
The issue turned out to be caused by JQuery Mobile.
I found the answer here: http://jquerymobile.com/demos/1.0a3/docs/pages/docs-pages.html
JQuery Mobile doesn't do full page reloads unless it's told to, so although the full html was returned, JQuery Mobile just replaced the page portion.
The key portion from the docs is:
"It's important to note if you are linking from a mobile page that was loaded via Ajax to a page with multiple internal pages, you need to add a rel="external" or data-ajax="false" to the link. This tells the framework to do a full page reload to clear out the Ajax hash in the URL. This is critical because Ajax pages use the hash (#) to track the Ajax history, while multiple internal pages use the hash to indicate internal pages so there will be a conflicts."
Recently, I encountered a similar problem.
In my case, Rails4's turbolinks suffered. Similarly as JQuery Mobile, turbolinks only updates the body part of a full page without updating the head part of the html when an intra-site link is clicked. I simply removed the require line for turbolinks in my application.js and the problem disappeared.