iOS Settings

Adobe AIR 3.3 and higher supports multitasking on iOS by enabling certain background behaviors:

• Audio

• Location updates

• Networking

• Opting out of background app execution

<InfoAdditions> 
    <![CDATA[ 
       <key>UIBackgroundModes</key> 
           <array> 
               <string>audio</string> 
            </array> 
    ]]> 
</InfoAdditions>

<InfoAdditions> 
    <![CDATA[ 
        <key>UIBackgroundModes</key> 
        <array> 
               <string>location</string> 
         </array> 
    ]]> 
</InfoAdditions>

<InfoAdditions> 
    <![CDATA[ 
       <key>UIApplicationExitsOnSuspend</key> 
       <true/> 
    ]]> 
</InfoAdditions>

AIR sets several entries in the generated Info.plist file to ensure that application and runtime features work correctly. You cannot define the following settings:

For iPad support, include the proper key-value settings for UIDeviceFamily within your InfoAdditions element. The UIDeviceFamily setting is an array of strings. Each string defines supported devices. The <string>1</string> setting defines support for the iPhone and iPod Touch. The <string>2</string> setting defines support for the iPad. If you specify only one of these strings, only that device family is supported. For example, the following setting limits support to the iPad:

<key>UIDeviceFamily</key> 
    <array> 
        <string>2</string> 
    </array>>

The following setting supports both device families (iPhone/iPod Touch and iPad):

<key>UIDeviceFamily</key> 
<array> 
    <string>1</string> 
    <string>2</string> 
</array>

Additionally, in AIR 3.7 and higher, you can use the forceCPURenderModeForDevices tag to force CPU render mode for a specified set of devices and enable GPU render mode for remaining iOS devices.

You add this tag as a child of the iPhone tag and specify a space-separated list of device model names. For a list of valid device model names, see forceCPURenderModeForDevices.

For example, to use CPU mode in old iPods, iPhones, and iPads and enable GPU mode for all other devices, specify the following in the application descriptor:

... 
<renderMode>GPU</renderMode> 
... 
<iPhone> 
... 
   <forceCPURenderModeForDevices>iPad1,1 iPhone1,1 iPhone1,2 iPod1,1 
   </forceCPURenderModeForDevices> 
</iPhone>

The requestedDisplayResolution element specifies whether your application should use the standard or high resolution mode on iOS devices with high-resolution screens.

<requestedDisplayResolution>high</requestedDisplayResolution>

In high-resolution mode, you can address each pixel on a high-resolution display individually. In the standard mode, the device screen will appear to your application as a standard resolution screen. Drawing a single pixel in this mode will set the color of four pixels on the high-resolution screen.

The default setting is standard. Note that for targeting iOS devices, you use the requestedDisplayResolution element as a child of the iPhone element (not the InfoAdditions element or initialWindow element).

If you want to use different settings on different devices, specify your default value as the requestedDisplayResolution element’s value. Use the excludeDevices attribute to specify devices that should use the opposite value. For example, with the following code, high resolution mode is used for all devices that support it except 3rd-generation iPads, which use standard mode:

<requestedDisplayResolution excludeDevices="iPad3">high</requestedDisplayResolution>

The excludeDevices attribute is available in AIR 3.6 and later.

You can register a custom URI scheme to allow your application to be invoked by a link in a web page or another, native application on the device. To register a URI scheme, add a CFBundleURLTypes key to the InfoAdditions element. The following example registers a URI scheme named com.example.app to allow an application to be invoked by URLs with the form: example://foo.

<key>CFBundleURLTypes</key> 
<array> 
    <dict> 
         <key>CFBundleURLSchemes</key> 
        <array> 
            <string>example</string> 
        </array> 
        <key>CFBundleURLName</key> 
        <string>com.example.app</string> 
    </dict> 
</array>

When your application is invoked through a custom URI, the NativeApplication object dispatches an invoke event. The URL of the link, including query parameters, is placed in the arguments array of the InvokeEvent object. You can use any number of custom URI schemes.

Add entries to a UIRequiredDeviceCapabilities array within the InfoAdditions element if your application should only be used on devices with specific hardware or software capabilities. For example, the following entry indicates that an application requires a still camera and a microphone:

<key>UIRequiredDeviceCapabilities</key> 
<array> 
    <string>microphone</string> 
    <string>still-camera</string> 
</array>

If a device lacks the corresponding capability, the application cannot be installed. The capability settings relevant to AIR applications include:

AIR 2.6+ automatically adds armv7 and opengles-2 to the list of required capabilities.

When a user switches away from an AIR application it enters the background and pauses. If you want your application to exit completely instead of pausing, set the UIApplicationExitsOnSuspend property to YES:

<key>UIApplicationExitsOnSuspend</key> 
<true/>

You can minimize your initial application download size by packaging a subset of the SWFs used by your application and loading the remaining (asset-only) external SWFs at runtime using the Loader.load() method. To use this feature, you must package the application such that ADT moves all ActionScript ByteCode (ABC) from the externally loaded SWF files to the main application SWF, leaving a SWF file that contains only assets. This is to conform with the Apple Store’s rule that forbids downloading any code after an application is installed.

ADT does the following to support externally loaded SWFs (also called stripped SWFs):

• Reads the text file specified in the <iPhone> element’s <externalSwfs> subelement to access the line-delimited list of SWFs to be loaded at execution time:

  <iPhone> 
     ... 
     <externalSwfs>FilewithPathsOfSWFsThatAreToNotToBePackaged.txt</externalSwfs> 
  </iPhone>

• Transfers the ABC code from each externally loaded SWF to the main executable.

• Omits the externally loaded SWFs from the .ipa file.

• Copies the stripped SWFs to the .remoteStrippedSWFs directory. You host these SWFs on a web server and your application loads them, as necessary, at runtime.

You indicate the SWF files to be loaded at runtime by specifying their names, one per line in a text file, as the following example shows:

assets/Level1/Level1.swf 
assets/Level2/Level2.swf 
assets/Level3/Level3.swf 
assets/Level4/Level4.swf

The file path specified is relative to the application descriptor file. Additionally, you must specify these swfs as assets in the adt command.

 For more information on this feature, including sample code, see External hosting of secondary SWFs for AIR apps on iOS, a blog post by Adobe engineer Abhinav Dhandh.