Pixelbox

I have always used Adobe’s ApplicationUpdater in my AIR apps, either with or without the UI. However every time I do I always find I need the functionality to force the user to update. This is normally due to an important feature or bug fix that I need pushed out to users, or just to make sure those users who never update don’t get too far behind (I recently found my dad had never updated any of his iPhone apps).

Update framework

When using the ApplicationUpdater (without the UI), you can easily force the install of all updates, but this isn’t very user friendly, and not a great experience. Often it’s far too time consuming to write your own UI for the update framework, so ideally I wanted to create a way of supporting required updates whilst using the existing UI as much as possible.

In order to do this I wrote a decorator for the ApplicationUpdaterUI which added the new event RequiredStatusUpdateEvent. This is dispatched when the updateDescriptor file is downloaded and includes the value of a new node called required (which you need to add to your update.xml file):

 
<?xml version="1.0" encoding="utf-8"?> 
<update xmlns="http://ns.adobe.com/air/framework/update/description/1.0"> 
	<version>2</version> 
	<url>http://www.pixelbox.net/demos/extendedAppUpdater/ExampleAirApp-2.air</url> 
	<description>
		Version 2
		- Lots of great new features
		- Required security patch
	</description>
	<required>true</required>
</update>

The text “true” will translate into a Boolean set to true, anything else will be false.

You can then add a listener for the (along with any default events), to tell your user they have to update to the new required version. This can be as simple as:

 
           private function onUpdate(event:RequiredStatusUpdateEvent):void
            {
                if (event.required && event.available)
                    // Required update available 
                else
                    // There isn't a required update, so leave it up to the ApplicationUpdaterUI
            }

From a UX point of view this works rather well. You can choose how your application responds to a required update, and don’t need to force the install in the background and restart the app. I like to change the state of the app, as well as letting the ApplicationUpdaterUI window open. If the user upgrades through the default UI, great, if not they will be presented with a new app state, telling them there is a required update, perhaps even why it’s important. You may even want to let them do some things but not others (such as letting them save their work, or finishing their current workflow). Either way it gives your app the choice of how it wants to behave.

I have created a little example app (with view source enabled) that uses the this code, as well as a .swc and the example app as a project.

• Example AIR Application
• Extended Updater swc file
• Example Air App project
• Example update descriptor XML file

If you install the above air file, you will be able to check for updates and receive a required update. When this happens the app’s main function is disabled and a message displayed telling the user to upgrade.

Please let me know if you have any questions, or would like to add to this little framework, good luck. If you want to create your own without using the default UI check out this article on Black Pepper