Development Update – Week of August 22nd, 2011

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Beta 3: Landing in about a week

We’re hard at work on the last big changes we want to get in before moving onto the first RC for 1.0. We just landed pushState (see below). The other items on deck are finishing our move to transitions for page animations, adding a bit more extensibility for JS-driven apps, and bringing really slick transitons and fixed headers for iOS5. We’ll keep you updated as we get closer. We are targeting 1.0 for the end of September.

pushState landed: Now, clean URLs with Ajax-based navigation

We’ve been working very hard to add pushSate to jQuery Mobile. After many months and at least 6 complete attempts and the hard work of everyone on the team to get this right, we’ve finally landed this feature. Since we use Ajax-based navigation extensively throughout a jQuery Mobile experience, we need to track each page with a hash change which can make for some pretty long and unwieldy URLs, but it was a small price to pay to supporting the Back button and deep linking to pages.

Now with the addition of pushState, we’re able to update the URL to the clean, standard path in browsers that support this feature. Technically, we use history.replaceState() because this allows us to layer pushState support and an enhancement to our existing, and widely supported, hashchange-based navigation model. We essentially let the hash change happen, then replace the URL with the clean, full path of the page in browsers that support this capability. This works in later versions of desktop Safari, Chrome, Firefox and Opera as well as Android (2.2+ and Honeycomb) and the soon-to-be-released iOS5. In browsers that don’t support this feature, the hash-based URLs will continue to work as the did before to preserve the ability to share and bookmark URLs.

The pushState feature is implemented as an extension to the the navigation code so it can be easily pulled out of the build if it’s not needed on a project. It’s also possible to turn this feature off by setting the pushStateEnabledglobal option to false, like this:

$.mobile.pushStateEnabled = false;

Pro tip: How to view the source of a jQuery Mobile page

Since we use Ajax to pull multiple pages into the DOM, if you view the source you will see the code for the first page you visited unless you use a web inspector tool like Firebug to view the current DOM. Now with pushState in place, to view the source, simple refresh the page and view source. In browsers that don’t support pushState, you need to edit the URL to remove the redundant part of the hash to get full page path, then reload to view the source. Hopefully, this will make exploring the docs a bit easier for people.

Page animations: Moving from keyframe to transitions

One of the things we hear a lot of people asking for is smoother page transitions, and we couldn’t agree more. In the current system, we use keyframe-based animated page transitions (originally borrowed and tweaked from jQTouch). Keyframe animation tends to be more verbose, and its support is mostly limited to Webkit browsers (with Firefox 5 as a recent exception), we’ve been working to change over to using CSS transitions for our page animations.

The advantage of moving to CSS3 transitions is that they are already supported by recent versions of both Firefox and Opera in addition to Webkit so this paves the way much broader support for page animations over time on mobile and desktop browsers. Transitions are also a bit more concise syntactically than keyframes for our use case, which tends to be a 1-step transition from point A to point B.

We were also hoping that transitions would behave more smoothly on certain platforms, as the keyframe-based animations tend to drop frames on several of the Android devices we’ve tested. In testing, however, this switch isn’t the panacea we’d hoped. In extensive testing in our lab, we’ve found that there is little difference in the smoothness of animations between keyframe and transitions on the browsers that already supported animations — iOS, Android and BB6/PlayBook.

In Firefox, the latest versions of the desktop browser support transitions but the most up-to-date version of Firefox Mobile (beta 5) we tested on Android didn’t seem support them, even though we heard reports that it did. So, the desktop experience will be improved with this upcoming change, but not mobile (yet).

Opera Mobile (not Mini) does currently support transitions, but the performance was so slow that we’ve decided to not add in the Opera-prefixed transition rules until they release an update. Opera desktop 10.5 and later do a good job with transitions, but we can’t flip the switch for desktop without harming the mobile browser since they both use the same vendor prefix so this will be added as soon as an update lands and has decent uptake.

Why transitions aren’t smooth: A complex set of factors

There are a few factors that contribute to the smoothness of page transitions.

If the animations are hardware accelerated so they are efficiently rendered by the GPU instead of through the CPU and software, they will be markedly smoother. On iOS, even older versions of the iPhone, the OS does a very good job with hardware accelerating with both keyframe and transitions so animations are quite smooth. On the other hand, Android 2.x devices may only show 1-2 frames during a page transition on some devices because of the lack of hardware acceleration. Rendering bugs/glitches in the transitions/keyframe implementations for the platform can also contribute to blinkiness.  Ariya Hidayat from Sencha has a great article on the technical details of hardware acceleration. Because we support web standards for our transitions, all we can do on this front is try to use the most effective CSS we can and the rapid innovation in devices and mobile operating systems should move this part along quickly.

The size of the document and the amount of area being re-drawn can also cause flashes of blank screen zones or blinks. For example, webkit uses a 1024×1024 tile so if a transition or animation causes the canvas to shift by more than that, a blink may occur if the browser doesn’t paint that area fast enough.

Scrolling the page into position can also be a significant cause of the transition smoothness. Here’s why: When a new page is pulled in via Ajax to enable an animated page transition, it’s added to the DOM and positioned with CSS to queue up the animation. So if we’re moving with a slide transition, the new page will be placed to the right of the current page so we can slide to the right and animate the new page into view.

Since both pages share the same viewport, we position the top of the new page next to the top of the current page which means that if you’re scrolled down on a page and click a link, we need to first scroll up to the top of the current page, then begin the slide transition. This scroll to the top action produces a noticeable jump, especially in underpowered devices. Because of this, you’ll notice that if you start a page transition when already scrolled to the top of the page, it will not jump or blink at all in most cases (some platforms always blink). We also remember and restore the original scroll position of a page that you revisit, so if you are scrolled down on a page and hit Back, you will see the current page scroll up, the slide animation will occur, then you will see the page scroll down to your original position.

We’ve tried every trick in the book to minimize the scrolling artifacts, but we now realize that this can’t be completely mitigated while still supporting the wide range of platforms the jQuery Mobile wants to cover without taking a fresh approach to the problem.

The future: Overflow and fixed positioning, for real this time

The way to eliminate this scrolling jumpiness is simple in theory: if each page has a height as tall as the screen allows, and scrolls internally using overflow, the browser will always be scrolled to the top. Unfortunately, regular CSS overflow has terrible support on mobile browsers, with almost no platform offering momentum scrolling via CSS overflow, and on iOS devices a user needs to scroll these regions with 2 fingers instead of 1. The only way to work around this currently is to use a JavaScript-based polyfill to mimic the scrolling using CSS3, with scripts such as our experimental scrollview plugin, scrollability, iScroll, or a host of other momentum scroller scripts.

Unfortunately, these scripted approaches tend to share a common flaw: they only work in a very narrow range of mobile browsers, usually just iOS and Android (with a lot of caveats and performance issues). Since scroller scripts need to intercept events to trigger the scrolling, they can prevent interaction with form elements and introduce a host of other serious usability issues if not applied with care and lots of testing. These scripts also need to be carefully targeted through support tests (and unfortunately UA detection), as they run the risk of making a page completely unusable on the mobile (and desktop) platforms they do not support. For web applications that are accessible on the public web, we don’t feel that this is an acceptable tradeoff for smoother transitions and fixed toolbars. In an installed native app, however, these scripts become a much more feasible option because the risk of usability problems is greatly reduced when only one browser needs to be supported.

For these reasons, we’ve tried our best to build on top of native browser scrolling, so we’re very excited by iOS5′s upcoming support for a touch-targeted version of overflow:auto|scroll , and proper support for position:fixed to allow for internal scrolling regions with the native momentum scrolling with CSS. This  will enable us to bring both truly “fixed” toolbars and super smooth transitions, all by using web standards and very little additional code. We’re working now on landing this as an improvement for 1.0 so we’re ready when iOS5 is released.

Think of this as an enhancement to what we have now: if the overflow: and -webkit-overflow-scrolling:touch properties are supported, we can make sure toolbars stay fixed and eliminate the scrolling jumps between transitions. Coupled with iOS’s already-excellent hardware-accelerated transitions, we’ll be very close to native performance.

Don’t other mobile platforms already support overflow?

Yes, but there’s a catch. Both Android Honeycomb and the Blackberry PlayBook support overflow: properties, but that’s not quite enough. If we simply placed an overflow: auto CSS rule on the page body, other popular mobile platforms like older versions of Android and iOS would essentially just clip off the content and make it effectively inaccessible (yes, you can can do a two-finger scroll gesture in iOS but nobody knows that).

The smart thing about Apple’s implementation for iOS5 is that they added an additional CSS property -webkit-overflow-scrolling:touch that allows us to test for this touch scrolling property and, if supported, add in the overflow rules for just those browsers. This is the only safe way to target overflow without resorting to complex and unmaintainable user agent detection.

We will be working with device and browser makers to encourage support for both these CSS-based properties because we strongly believe that this a critical piece needed to build rich mobile web apps.  So let’s all ask other mobile companies to follow Apple’s lead here and support both -webkit-overflow-scrolling:touch and overflow: properties ASAP.

The project will add any vendor-prefixed additions to touch scrolling property if, for example, Opera, Firefox or Microsoft added this support. Once people see how much better page transitions and fixed toolbars are on iOS5, we’re hoping this will be supported quickly by other browsers.

JS-based scroller scripts may still have a place in this new world as a polyfill for browsers that dont’ yet support these new CSS capabilities but we see this as a brief, interim tool in the evolution of the mobile web. Once implemented, it will likely be easier to add such a shim to your codebase as well.

The team has spent a ton of time working on trying to improve transitions because we know this is an incredibly important feature. We hope this helps to provide a bit of useful detail on the challenges we face and how we plan on moving forward.

Notable commits this week

Fix to check the domCache option before rebinding the page remove on select menu. When closing a fullpage select menu we need to check the domCache option before rebinding the page remove handler. If domCache is true the page remove wasn’t bound in the first place, so binding it on menu close will cause the removing of a page that mustn’t be removed. Thanks SamuelKC!

Anchor buttons active class not removed properly (Issue #1405) – Moved assignment of $activeClickedLink to the vclick handler in charge of adding the active state

Fixed closing the custom select dialog – The picker wasn’t being closed correctly. Thanks MichelHartmann!

Ellipses too aggressive – truncating overflow early on lists, buttons, form elements (issue 779) – Adjusted padding on buttons

Sponsor thanks: Adobe

We’d like to thank Adobe Systems Inc. for both contributing a generous donation at the start of the jQuery Mobile project and for sponsoring the development time of Kin Blas (@kinblas) for the past year. To top it off, they also recently just hired another mobile team member, John Bender (@johnbender) to work on the project in a dedicated way. Kin and John are an important part of jQuery Mobile team and their amazing talent and drive has been critical to the success of this project. we wanted to acknowledge Adobe for their generous support as a premier sponsor of the project. Thanks Adobe!

As you probably know, Adobe is has been included jQuery Mobile in the new Dreamweaver CS 5.5 release and includes a lot of great tools to make it easy to build mobile-optimized sites and apps with jQuery Mobile.

If you are looking to support the jQuery Mobile project, we are actively looking for corporate sponsors to provide donations or commit to long-term developer involvement. To learn more, please contact Todd Parker, project lead to discuss opportunities for supporting the project and open source.

New jQuery Mobile pagination plugin

Team member Scott Jehl of Filament Group just posted a cool new pagination plugin that makes it super simple to allow for swiping between separate jQuery Mobile pages. Perfect for navigating through photo galleries, articles and more.

The Pagination plugin creates touch-drag navigation between separate HTML pages. Simply add this plugin to your page and link together documents via ordinary HTML anchors. The linked pages will pre-fetch, and in browsers that support touch events, you’ll be able to drag between the linked pages, while desktop users can navigate with mouse or keyboard. Like all navigation in jQuery Mobile, this plugin ties into your browser’s history, so bookmarking, and using the browser’s back and forward buttons work as expected!

Photoswipe: Updated version out

The very cool Photoswipe plugin adds a slick gallery slideshow tool that is compatible with jQuery Mobile. PhotoSwipe is a FREE HTML/CSS/JavaScript based image gallery specifically targeting mobile devices.

The latest 2.0.2 version adds the ability to drag swipe between photos and adds a number of refinements.

For a nice example of jQuery Mobile, responsive design and Photoswipe, check out this portfolio site.

Get the latest builds on the jQuery CDN

To take advantage of the daily improvements happening in jQuery Mobile, be sure to check out out the new daily and latest builds that are now available on the jQuery CDN for hotlinking. This allows you to upgrade to the latest code without waiting for the next official release. Here are the three files to include in the head of your page to always be viewing the latest in Git:



If you want to a quick preview of our latest progress, visit www.jquerymobile.com/test. This is a live demo of the docs synced live to the jQuery Mobile GitHub repo. This is helpful to check before filing an issue in the tracker to see if we've already fixed a bug you see in the last stable release. Please keep in mind that this the unstable, development version so we don't recommend linking to the latest in a production site or app, but it's great for development and testing.

Development Update – Week of August 8th, 2011

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We’re really happy about the Beta 2 release and are now working on the last batch of improvements we want to land for 1.0. The team is very close to landing the re-vamped transitions and pushState branches and we’re actively fixing lots of bugs as we go.

jQuery Mobile nominated for two .net Awards 2011

We’re happy to see that jQuery Mobile has been nominated for for two .Net awards - the annual Awards are organised by .net magazine – the world’s bestselling magazine for web designers. The categories are Innovation of the Year & Open Source App of the Year! We’d love your support by voting for jQuery Mobile.

Listview filter callback added: Hook to add custom search logic

Now If you want to change the way in which list items are filtered, ie fuzzy search or matching from the beginning of the string, you can configure the callback used internally by defining $.mobile.listview.prototype.options.filterCallback during mobileinit or after the widget has been created with $("#mylist").listview('option', 'filterCallback', yourFilterFunction). Any function defined for the callback will be provided two arguments. First, the text of the current list item and second the value being searched for. A truthy value will result in a hidden list item. The default callback which filters entries without the searchValue as a substring is described below:

        
function( text, searchValue ){
  return text.toLowerCase().indexOf( searchValue ) === -1;
};
        

The documentation for lists has been updated to add this feature. Thanks to project707 for all the hard work on this feature and the helpful input of jeffholmes.

Notable commits this week

Added a simple filterCallback in the listview options to delegate complex search logic to end users. This allows you to drop in any search pattern matching logic needed without adding too much complexity to the core filtering code.

Fix for Split Button List dialog having no background and weird line from background image. Thanks jgable!

Brought back the page content div theme inheritance from b1 (issue 2221) Thanks to abdulqadir for the suggestion.

Fix nested waiting-for-dom for initializePage. Using dom-ready within dom-ready meant that initializePage went to the end ofthe queue. That brought problems when other dom-ready code expected jQM to beset up, capable of changing pages and so on. But because $.mobile.pageContaineris also set in initializePage, changePage and others didn’t work. Thanks moll!

Fixed an error in the array reference that was causing support tests to not test properties as they should.

New book: Master Mobile Web Apps with jQuery Mobile


Matt Doyle recently released a new book on jQuery Mobile called “Master Mobile Web Apps with jQuery Mobile“. It’s very detailed 300+ page eBook in PDF format that is well-written and updated to reflect the latest Beta 2 release. Matt will be updating the book when we hit 1.0 and offer a free update for people who buy the book now.

The book is now available for sale. A sample chapter and demo to-do app featured in the book are available too. Here’s a description:

“Master Mobile Web Apps with jQuery Mobile”” teaches you how to quickly create great mobile web apps using jQuery Mobile. It’s a fully-up-to-date comprehensive guide which covers:

• How to get up and running quickly with the latest version of jQuery Mobile (Beta 2)

• Building pages, buttons, toolbars, dialogs, forms and interactive list views — using nothing but HTML

• Theming your apps to give them a unique look and feel

• How to integrate your own JavaScript code with the jQuery Mobile API

• How to create a fully-functioning, multi-user task manager app using jQuery Mobile, PHP and MySQL

Sponsor thanks: Jive Software

We’d like to thank Jive Software for contributing the time and expertise of their developer, Ghislain Seguin, to the core jQuery Mobile team. Ghislain has been a tremendous help over the last three months and we wanted to recognize the generous donation that Jive Software has made to this project. Jive Software is a software company from Palo Alto that has an enterprise social networking platform that allows companies to engage employees, customers, and the social web.

If you are looking to support the jQuery Mobile project, we are actively looking for corporate sponsors to provide donations or commit to long-term developer involvement. To learn more, please contact Todd Parker, project lead to discuss opportunities for supporting the project and open source.

Get the latest builds on the jQuery CDN

To take advantage of the daily improvements happening in jQuery Mobile, be sure to check out out the new daily and latest builds that are now available on the jQuery CDN for hotlinking. This allows you to upgrade to the latest code without waiting for the next official release. Here are the three files to include in the head of your page to always be viewing the latest in Git:



If you want to a quick preview of our latest progress, visit www.jquerymobile.com/test. This is a live demo of the docs synced live to the jQuery Mobile GitHub repo. This is helpful to check before filing an issue in the tracker to see if we've already fixed a bug you see in the last stable release. Please keep in mind that this the unstable, development version so we don't recommend linking to the latest in a production site or app, but it's great for development and testing.

jQuery Mobile Beta 2 Released!

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The jQuery Mobile team is happy to announce the release of Beta 2. This brings a bunch of big improvements to the library including: decoupled widgets so you can include only the components you need, DOM cache management for less memory use, a page pre-cache option, more flexible page structure, improved checkbox and radiobutton designs, advanced features for developers building dynamic JS-driven sites, and even broader device support. It’s been a busy 5 weeks since Beta 1 and we’re really happy with the direction and velocity of the project as we head towards 1.0.

Beta 3 coming – We have a few key improvements we want to land before we switch gears to focus on bug fixes and performance for the first RC for 1.0. Look for Beta 3 within the next month that will include pushState support, improved transitions with support for Firefox and Opera, and even more developer extensibility hooks.

Note that jQuery Mobile 1.0 will require jQuery core 1.6.2 as a baseline. Going forward, we’ll be supporting the two latest major versions of core but we’re starting with a cleaner baseline for launch. Here is a summary of what’s new and improved in Beta 2.

Demos & docs | Supported Platforms | Key changes | Change log | Upgrade notes | Download & CDN

Platform support: Expanded for Beta 2

In Beta 2, we’ve added broader support of CSS gradient rules for Opera and Firefox, brought support and testing for Android 2.3 phones and Honeycomb tablets, HP Palm WebOS 3.0 tablets, and added B grade support for newer Nokia S60 devices.

We’re happy to announce that jQuery Mobile Beta 2 now supports Nokia Series 60 smartphones. We’ve had to bump this platform down to B grade support because this platform doesn’t properly support hashchange events in the history stack. This means that Nokia devices will get the enhanced experience except without the Ajax-based animated page transitions.

At this stage, jQuery Mobile works on the vast majority of all modern desktop, smartphone, tablet, and e-reader platforms. In addition, feature phones and older browsers are also supported because of our progressive enhancement approach. We’re very proud of our commitment to universal accessibility through our broad support for all popular platforms.

Our graded support matrix was created over a year ago based on our goals as a project and since that time, we’ve been refining our grading system based on real-world device testing and the quickly evolving mobile landscape. To provide a quick summary of our browser support in Beta 1, we’ve created a simple A (full), B (full minus Ajax), C (basic) grade system with notes of the actual devices and versions we’ve been testing on in our lab.

The visual fidelity of the experience is highly dependent on CSS rendering capabilities of the device and platform so not all A grade experience will be pixel-perfect but that’s the nature of the web. We’ll be adding additional vendor-prefixed CSS rules to bring transitions, gradients and other visual improvements to non-WebKit browsers in future releases so look for even more added visual polish as we move towards 1.0.

A-grade – Full enhanced experience with Ajax-based animated page transitions.

  • Apple iOS 3.2-5.0 beta: Tested on the original iPad (3.2 / 4.3), iPad 2 (4.3), original iPhone (3.1), iPhone 3 (3.2), 3GS (4.3), and 4 (4.3 / 5.0 beta)
  • Android 2.1-2.3: Tested on the HTC Incredible (2.2), original Droid (2.2), Nook Color (2.2), HTC Aria (2.1), Google Nexus S (2.3) NEW. Functional on 1.5 & 1.6 but performance may be sluggish, tested on Google G1 (1.5)
  • Android Honeycomb NEW – Tested on the Samsung Galaxy Tab 10.1
  • Windows Phone 7: Tested on the HTC 7 Surround
  • Blackberry 6.0: Tested on the Torch 9800 and Style 9670
  • Blackberry Playbook: Tested on PlayBook version 1.0.1 / 1.0.5
  • Palm WebOS (1.4-2.0): Tested on the Palm Pixi (1.4), Pre (1.4), Pre 2 (2.0)
  • Palm WebOS 3.0 NEW – Tested on HP TouchPad
  • Firebox Mobile (Beta): Tested on Android 2.2
  • Opera Mobile 11.0: Tested on the iPhone 3GS and 4 (5.0/6.0), Android 2.2 (5.0/6.0), Windows Mobile 6.5 (5.0)
  • Kindle 3: Tested on the built-in WebKit browser included in the Kindle 3 device
  • Chrome Desktop 11-13 – Tested on OS X 10.6.7 and Windows 7
  • Firefox Desktop 3.6-4.0 – Tested on OS X 10.6.7 and Windows 7
  • Internet Explorer 7-9 – Tested on Windows XP, Vista and 7 (minor CSS issues)
  • Opera Desktop 10-11 - Tested on OS X 10.6.7 and Windows 7

B-grade – Enhanced experience except without Ajax navigation features.

  • Blackberry 5.0: Tested on the Storm 2 9550, Bold 9770
  • Opera Mini (5.0-6.0) - Tested on iOS 3.2/4.3
  • Windows Phone 6.5 – Tested on the HTC
  • Nokia Symbian^3 NEW – Tested on Nokia N8 (Symbian^3), C7 (Symbian^3), also works on N97 (Symbian^1)

C-grade – Basic, non-enhanced HTML experience that is still functional

  • Blackberry4.x: Tested on the Curve 8330
  • All older smartphone platforms and featurephones – Any device that doesn’t support media queries will receive the basic, C grade experience

Not Officially Supported – May work, but haven’t been thoroughly tested or debugged

  • Meego – Originally a target platform, but Nokia decision to relegate this platform to “experimental”, we are considering dropping support.
  • Samsung Bada – The project doesn’t currently have test devices or emulators, but current support is known to be fairly good. Support level undecided for 1.0.

KEY CHANGES

Widgets: Now decoupled for flexible builds

We’ve wanted to decouple all our widgets from the page plugin for a long time now and we’re happy to announce that we finally landed this change. So what exactly does decoupled mean anyway? Well, the individual widgets and utilities have always been broken out into separate script files. However, the page plugin was responsible for handling the auto-initialization all of the official plugins found in the markup at page creation. This situation made it impossible to remove plugins you don’t need without causing errors, and generally set a bad precedent for future widget additions.

Now, pretty much all the UI widgets in the jQuery Mobile library are completely decoupled so they can simply be deleted if not needed for a particular project. This change allows you to dramatically reduce the size of the library by only including the specific set of widgets or features you need, in addition to the handful of required, core files. While we still plan to do more decoupling and cleanup, the following files are now decoupled and can safely be removed from the make file before you do a custom build:

  • page header/content/footer
  • collapsible
  • controlgroup
  • fieldcontain
  • fixheaderfooter
  • button
  • checkboxradio
  • select
  • slider
  • textinput
  • links theming
  • listview
  • navbar
  • grid

We will work on a dependency map because a few widgets rely on others to work. For example, the button markup plugin is called by many of the widgets above, so it can only be excluded but if you’re not using any of the widgets that depend on buttons.

We’re still working out our recommendations for mapping plugin dependencies and decoupling things even further. Ultimately, this will be surfaced in a download builder tool, so stay tuned!

New “create” event: Easily enhance all widgets at once

While the page plugin no longer calls each plugin specifically, it does dispatch a “pagecreate” event, which most widgets use to auto-initialize themselves. As long as a widget plugin script is referenced, it will automatically enhance any instances of the widgets it finds on the page, just like before. For example, if the selectmenu plugin is loaded, it will enhance any selects it finds within a newly created page.

This structure now allows us to add a new create event that can be triggered on any element, saving you the task of manually initializing each plugin contained in that element. Until now, if a developer loaded in content via Ajax or dynamically generated markup, they needed to manually initialize all contained plugins (listview button, select, etc.) to enhance the widgets in the markup.

Now, our handy create event will initialize all the necessary plugins within that markup, just like how the page creation enhancement process works. If you were to use Ajax to load in a block of HTML markup (say a login form), you can trigger create to automatically transform all the widgets it contains (inputs and buttons in this case) into the enhanced versions. The code for this scenario would be:

$( ...new markup that contains widgets... ).appendTo( ".ui-page" ).trigger( "create" );

Create vs. refresh: An important distinction

Note that there is an important difference between the create event and refresh method that some widgets have. The create event is suited for enhancing raw markup that contains one or more widgets. The refresh method that some widgets have should be used on existing (already enhanced) widgets that have been manipulated programmatically and need the UI be updated to match.

For example, if you had a page where you dynamically appended a new unordered list with data-role=listview attribute after page creation, triggering create on a parent element of that list would transform it into a listview styled widget. If more list items were then programmatically added, calling the listview’s refresh method would update just those new list items to the enhanced state and leave the existing list items untouched.

New DOM cache management feature: On by default

Since animated page transitions require that the page you’re on and the one you’re transitioning to are both in the DOM, we add pages to the DOM as you navigate around. Until now, those pages would continue to stay in the DOM until you did a full page refresh so there was always a concern that we could hit a memory ceiling on some devices and cause the browser to slow down or even crash.

For Beta 2, we added a simple mechanism to keep the DOM tidy. It works like this: whenever a page is loaded in via Ajax, it is flagged for removal from the DOM once you navigate away to another page (technically, on pagehide). If you return to a deleted page, the browser may be able to retrieve the file from it’s cache, or it will re-request it fro the sever if needed. In the case of nested lists, we remove all the pages that make up the nested list once you navigate to a page that’s not part of the list. Pages that are included in a multi-page setup won’t be affected by this feature at all – only pages brought in by Ajax are managed this way by jQuery Mobile.

A new page option called domCache controls whether to leave pages in the DOM as a way to cache them (the way things used to work) or keep the DOM clean and remove hidden pages (the new way). By default, domCache is set to false to keep the DOM size actively managed. If you set this to true, you need to take care to manage the DOM yourself and test thoroughly on a range of devices.

To set the domCache option on an individual pages in order to selectively cache a page, you can either add the data-dom-cache="true" attribute to the page container or set it programmatically like this:

elem.page({ domCache: true });

The domCache option can also be set globally. This is how to turn DOM caching back on so it works like it did originally:

$.mobile.page.prototype.options.domCache = true;

 

Page pre-fetch page option added

Another cool feature we recently added is the ability to flag pages that should be pre-fetched by Ajax. For example, if you’re building a photo gallery with each photo on a separate HTML page, you can pre-fetch the previous and next pages in the slideshow sequence so they will display immediately without the Ajax loader. It’s simple to use: just add a data-prefetch attribute to any link in the page and the framework will lazy load the pages into the DOM in the background. We recommend building your apps as a series of individual, linked HTML documents for each page for performance yet we see a lot of people using multi-page templates and even nested lists (yikes) as a way to essentially pre-load content. We hope this feature will encourage developers to use standalone, external pages with selective pre-caching instead of relying as much on multi-page setups.

<a href="foo/bar/baz" data-prefetch>link text</a>

Pages can also be pre-fetched programmatically by calling $.mobile.loadpage( url ). Pre-fetching links will naturally cause additional HTTP requests that may never be used, so it’s important to use this feature only in situations where it’s highly likely that a page will be visited.

New global config option: autoInitializePage

For advanced developers who want more control over the initialization sequence of a page, we’ve just added a new autoInitializePage global config option. Setting this to false disables auto-initialization of plugins on page creation to allow developers to manipulate or pre-process markup before manually initializing the page later on. By default, this option is set to true so things work just like they always did.

Loading message: Now configurable at runtime

Previously, you could customize the loading text message on initialization as an option, but you couldn’t modify it on the fly from within a page if you wanted a different message for the particular situation. We just landed an improvement so you can set the contents of the loading message programmatically at runtime. The syntax is the same as it’s always been, you can just use it more flexibly:

$.mobile.loadingMessage = "My custom message!";

Configurable swipe event thresholds added

There were a number of hard-coded constants in the jquery.mobile.event.js swipe code. For developers who need to tweak those constants  to allow a greater vertical displacement and still register a swipe, this new feature allows them to be adjusted. Thanks to mlitwin for contributing this.

  • scrollSupressionThreshold (default: 10px) – More than this horizontal displacement, and we will suppress scrolling
  • durationThreshold (default: 1000ms) – More time than this, and it isn’t a swipe
  • horizontalDistanceThreshold (default: 30px) – Swipe horizontal displacement must be more than this.
  • verticalDistanceThreshold (default: 75px) – Swipe vertical displacement must be less than this.

Backtrack: We’ve switched back from vclick to click for links

In Beta 1, we decided to use our custom vclick event for handling Ajax links to improve responsiveness and to hide the URL bar on the iPhone and Android phones. Even though we did quite a bit of testing before landing this for Beta 1, we began to hear feedback that this change was causing some significant issues out in the wild including:

  • Multiple click events causing navigation and form element issue – In certain situations, when tapping an element, tap/click events seem to fire twice on links and is due to edge cases where the target of the touch event and mouse event don’t match due to how the browsers calculate tolerances for these events. This is most pronounced on Android 2.1, but affected most WebKit-based browsers to varying degrees when a tap events occured near the edge of an element.
  • Click handlers in custom scripts didn’t “work” anymore – if a script bound only to click events on the document, the global vclick feature could interfere because the touch events may supercede click events so it events wouldn’t appear to trigger.

Based on a lot of detailed testing and analysis, we’ve decided to roll back to using standard click events on links instead of using the custom vclick event because it’s the only reliable way to support all our target browsers. There are two important things to note in this change:

  • URL bar hiding isn’t quite as slick as in Beta 1, but link handling is obviously much more important. The good news is that there is still a significant improvement from Alpha 4.1: although URL bar may appear briefly it overlays the page in iOS instead of pushing down content and causing a re-draw blink. We methodically tried every technique we could to keep the URL bar hidden but there is unfortunately a Safari bug (even in the latest Beta 2 of iOS 5) that makes it impossible to hide the bar reliably.
  • The useFastClick global option introduced in Beta 1 is now removed because we’re not using vclick globally anymore on links and don’t recommend doing this going forward. We hardly knew ye…

Page wrapper: Now optional

The framework is now more flexible with document structure so now the data-role=page wrapper element is optional. This will ease integration with existing sites, as well as mashups with external content. Previously, if you didn’t wrap your page in a container with this role, the framework wouldn’t enhance the page widgets but now it doesn’t need a page wrapper in the markup to trigger initialization.

The page, header, content, and footer data-role elements have always been optional, but now with this page wrapper change, there is no required markup at all - just start building you page content. Here is an example of a page with none of these structural elements in the markup and everything works great.

Behind the scenes, the framework will inject the page wrapper if you don’t include it in the markup because it’s needed for managing pages, but the starting markup can now be extremely simple. Note that in a multi-page setup, you are required to have page wrappers in your markup in order to group the content into multiple pages.

Checkboxes and Radio buttons: New, Simpler design

Now onto fun fun stuff: the previous design for checkboxes or radio buttons highlighted the entire button background to the active state. We’ve wanted to tweak this for some time because having the full button switch tothe active state could be a bit overwhelming visually, especially on a check list with multiple items selected.

To make these controls a bit simpler visually and also fall in-line with standard UI conventions, now just the check or radio form element flips to the active state instead of the whole button. Note that the horizontal, grouped check and radio groups still flip the while label to the active state color because we hide the form element in these cases.

Gradients: Expanded platform support

We just added additional vendor-prefixed rules for CSS3 background gradients to increase browser support of this feature. There are now Opera (-o) and Internet Explorer (-ms) prefixed gradient rules in addition to the standard, non-prefixed version. Thanks to Paul Irish CCS3 Please for the slick formatting ideas for these rules:


background-image: -webkit-linear-gradient(top, #3c3c3c, #111); /* Chrome 10+, Saf5.1+ */
background-image:    -moz-linear-gradient(top, #3c3c3c, #111); /* FF3.6 */
background-image:     -ms-linear-gradient(top, #3c3c3c, #111); /* IE10 */
background-image:      -o-linear-gradient(top, #3c3c3c, #111); /* Opera 11.10+ */
background-image:         linear-gradient(top, #3c3c3c, #111); /* Standard, non-prefixed */

This now means that our background gradients work in WebKit, Firefox, Opera, Internet Explorer 10 and any other browser that supports the standard, non-prefixed rule. As we mentioned in an earlier blog post, we had to remove the -ms filter gradient rules due to a rendering issue in IE9 that conflicts with border radius and won’t be fixed by Microsoft. This means that older versions of IE will just see a flat background color, including WP7 and the forthcoming Mango release. More info on this bug and decision can be found at issue #2046. This change has been rolled into both the Default and Valencia themes.

All code formatting: Cleaned up & JSlint-ready

Thanks to an intense 24 hour sprint by Rick Waldron of Bocoup, all our code formatting now conforms with with the jQuery core styleguide for whitespace and organization. This also makes the library work with JSLint and other validation tools.

API documentation: Now underway

We’ve been trying a number of different ideas internally on how to add in more traditional API-style docs to the demos & docs site and have a proposed solution that essentially adds a simple tab strip to all the plugin detail pages where we can document the options, methods and events that a more technical developer might need. We’ve tried to strike a balance between presenting the simpler, markup-based approach that a designer may need and the more advanced script-driven details that a developer requires.

We’re looking for volunteers to help us apply this style of docs throughout the rest of the system. To participate, learn more about on how to help us write API docs. Thanks to ovargas27 for already jumping in and lending a hand.

Beta 1 upgrade notes

The useFastClick global option introduced in Beta 1 is now removed because we’re not using vclick globally anymore on links.

Change log

Fix for cached page removal breaking dialog sized select menus (issue 2181)

Added a configurable timeout to $.mobile.loadPage to give pages that are being fetched from cache a little time to load before a loading message appears. Note: if the delay ends up needing to be longer than 300ms or so to suit some devices,we may not keep this feature.

Exposed automatic initialization selectors on most widgets – The new option, initSelector is accessed through each of the widget plugins (select, slider, etc.) that expose options through the widget factory. This is used to define the selectors (element types, data roles, etc.) that should be used as the trigger to automatic initialization of each widget plugin. This allows developers to apply auto-initialization in more flexible ways.

Restored degradeInputs page option (issue 2123) – We originally had a degradeInputs option as part of the page plugin that would allows you to find a certain type of form element (say input type=”range”) and degrade it into another type (input type=”number”) either because the browser support is so uneven or if you built a custom enhancement for the primary type (like a custom slider) and you don’t want the native implementation to interfere. Now added back in a decoupled plugin, but the API is the same.

Prevent ‘Unspecified error’ when we use an IFrame on IE9 (issue 2064)  - Add try/catch block to prevent the error. Thanks SamuelKC

Updated Valencia theme to match new CSS syntax (issue 2087) – After our request for help on this, and Mayank Varia came through with an update for this theme so thanks!

Error in new page.sections js when data-add-back-btn=”true” on page (issue 2119) -Fixed a problem when pages have the data-add-back-btn set to true causing an error. Thanks jgable!

Email input type doesn’t receive input field styles (issue 2117) –  When using email as the input type for an input field, jQuery Mobile does not correctly enhance them post-decoupling. Thanks commadelimited! Also fixed URL and tel input types for the same regression.

Hide loading message for loadPage should be to not show the loading message – It’s default use case is to fetch a page that is not yet active so this is distracting. However, changePage should cause it to show because loadPage is being called during a page change. This was causing the loader to show when using the new page precache option.

Fix for URL handing in navigation with relative URLs – Now you can call $.mobile.loadPage with a relative path and it will load the page correctly, regardless of whatever page you are linking from.

Removed the nonHistorySelectors option, which was no longer in use after the nav refactor.

Fix for rounded corners in collapsible Set (issue #1931) - The first section in a collapsible set has rounded bottom corners when not expanded (shouldn’t have .ui-corner-bottom class), and the last section does not have rounded corners when collapsed (should have .ui-corner-bottom class). Thanks  ryanneufeld !

Checkbox list with same name do not allow multiple selection (issue #1851) - The checkboxradio plugin treats a check box list with same value for the name attribute for the check boxes as radio buttons. Thanks Tigbro!

Rounded corner login for inset lists  with two items (issue 1996) - The top corner style doesn’t get applied in an inset list with two items (other number of items work fine). Thanks eugenb1!

Close button behavior fixes (Issues #1618#1692,#1750)- Abstracted out some of the page hide behavior to fix issues with the close button not returning focus to the button after closing. Also fixes an issue where a full page custom menu would open as a misplaced small custom menu the second time it opens (if the menu was closed via the custom close button).

Changed padding-box to padding for -moz-background-clip per this spec

Slider onChange event is launched on page load (issue #1526) - the onChange event was triggered when the page loads  instead of only when the slider’s value is changed.

Disappearing text in IE7 (issue #2058) – Text would only appear on mouseover in certain circumstances due to a rendering bug in IE (shocker!). Fixed by adding the zoom: hack.

XSS risk with XHR level2 cross domain request (issue #1990) - jQuery mobile can load other domain’s html so there is a security risk, as it can XSS or display fake contents. Created new option for $.mobile.ajaxCrossDomainEnabled and set the defaultto false

Switch back to processing link clicks on the “click” event because it really is the only reliable way across all the devices we support. Fixes any of the double click events, missed clicks or click event not being processed. Also, removed the useFastClick option and documentation references since using vclick isn’t a workable solution for links.

mobile.changePage not working on BB5 (issue #1907)- multi-page docs don’t work, and clicking a link cause a ”page is too large” error. The fix for this was to tweak the regex related.

Fix for the mysterious “page is too large” error on Blackberry 5 prior to beta 1. Turns out this little code was enough to invoke the error: ”/dir1/dir2″.replace(/\/?/, “”); Rewrote the regexp in path.makePathAbsolute() that was stripping leading slash, and trailing filename/slash. This gets around the problem. Special thanks to @adambiggs for helping us test 33 iterations when trying to narrow down the cause!

Fixed form buttons no longer submitting forms in Internet Explorer 8

Corrected corner styling issue with listview refresh on growing lists (issue #1470) – If list items were appended and the refresh() method called, the correct corners were not being assigned.

Fixed incorrectly calculated path of forms (issue #1923)- Added code to calculate whether to choose the documentUrl or the page Url in the case where an action is not specified on a form element. Fixed bug in the navigation “submit” handler where an error was being thrown if “type” was not specified.

Hitting enter in search filter now doesn’t not submit the form – Since this is a client-side filter, we want to prevent submitting the form. Thanks adamvaughan

Remove unnecessary ajax call and duplicate DOM nodes when refreshing a page with a dialog visible (issue #1913) - This was causing duplicate dialog elements inthe DOM. Thanks Sunpig!

Controlgroup now filters on visible buttons when adding first and last classes for rounded corners. If you hide the first or last button in a controlgroup and then call refresh on it, it won’t add the right classes to the newly promoted first/last button.

Removed param “refresh” sent to .controlgroup since it’s not a $.widget

Tweaked styles for select menu text running off side of list – Seen when using the custom select menus only

Updated Valencia theme for the updated check and radio styles

Fixed swatch letter typo for E button in theme CSS (Issue #1894)- it said ui-bar-d instead of ui-bar-e. . Thanks app42!

Moved collapsible sets (accordions) in docs into a standalone page for better visibility, updated section nav on other pages and index page to link to it.

Moved our form binding into the _registerInternalEvents callback, to ensure it’s not bound until after mobilinit.

Download

We provide CDN-hosted versions of jQuery Mobile for you to include into your site. These are already minified and compressed – and host the image files as well. It’ll likely be the fastest way to include jQuery Mobile in your site.

CDN-Hosted JavaScript:

CDN-Hosted CSS:

Copy-and-Paste Snippet for CDN-hosted files (recommended):

<link rel="stylesheet" href="http://code.jquery.com/mobile/1.0b2/jquery.mobile-1.0b2.min.css" />
<script src="http://code.jquery.com/jquery-1.6.2.min.js"></script>
<script src="http://code.jquery.com/mobile/1.0b2/jquery.mobile-1.0b2.min.js"></script>

 

If you want to host the files yourself you can download a zip of all the files:

ZIP File: