Downloading Expansion Files

Once you have setup the Expansion Files ANE you should provide information about your expansion files. This is done by creating an ExpansionFile object and passing it to the ANE's addExpansionFile function.

You can then check if the files have already been downloaded using the expansionFilesDelivered function. This returns true if the files have been downloaded either as part of the install from Google Play or in a previous run of the application. If the files haven't been downloaded you should start the download process and wait for the ExpansionFilesEvent.COMPLETE event to process the files.

Note: expansionFilesDelivered will check the file size of the downloaded file to the filesize you have specified so it is very important that you create your ExpansionFile with the exact size of the file you have uploaded to the Play Store. If you don't then this will always return false and may incorrectly download your file on every launch.

The following example shows the major events in this process and the suggested method of checking for the existence of expansion files.

public static const BASE64_PUBLIC_KEY   : String = "YOUR_LICENSING_PUBLIC_KEY";
public static const SALT        : Vector.<int> = Vector.<int>( [ 1, 43, -12, -1, 54, 98, -100, -12, 43, 2, -8, -4, 9, 5, -106, -108, -33, 45, -1, 84 ]); 

ExpansionFiles.service.setup( BASE64_PUBLIC_KEY, SALT );

ExpansionFiles.service.addEventListener( ExpansionFilesEvent.CONNECTED,     connectedHandler );
ExpansionFiles.service.addEventListener( ExpansionFilesEvent.STATE_CHANGED, stateChangedHandler );
ExpansionFiles.service.addEventListener( ProgressEvent.PROGRESS,            progressHandler );
ExpansionFiles.service.addEventListener( ExpansionFilesEvent.COMPLETE,      completeHandler );

// Add the details of your expansion file(s)
var expansionFile:ExpansionFile = new ExpansionFile( ExpansionFile.MAIN, 1001002, 233017 );
ExpansionFiles.service.addExpansionFile( expansionFile );

// Check if the files have been delivered / downloaded already
if (!ExpansionFiles.service.expansionFilesDelivered())
{
    // Start the downloading
    ExpansionFiles.service.download();
}
else
{
    // Already have expansion files - use as required
}

private function connectedHandler( event:ExpansionFilesEvent ):void
{
    trace( "connectedHandler()" );
}

private function stateChangedHandler( event:ExpansionFilesEvent ):void
{
    trace( "stateChangedHandler(): " + event.state );
}

private function completeHandler( event:ExpansionFilesEvent ):void
{
    trace( "completeHandler()" );
    // Read your expansion files
}

private function progressHandler( event:ProgressEvent ):void
{
    trace( "progressHandler( " + event.progress.toString() + " )" );    
}