- oldState
- An open, read-only Android.OS.ParcelFileDescriptor pointing to the last backup state provided by the application. May be null, in which case no prior state is being provided and the application should perform a full backup.
- data
- An open, read/write Android.App.Backup.BackupDataOutput pointing to the backup data destination. Typically the application will use backup helper classes to write to this file.
- newState
- An open, read/write Android.OS.ParcelFileDescriptor pointing to an empty file. The application should record the final backup state here after writing the requested data to the data output stream.
Based on oldState, determine which of the files from the application's data directory need to be backed up, write them to the data stream, and fill in newState with the state as it exists now. When oldState is null, all the files will be backed up.
This should only be called directly from within the Android.App.Backup.BackupAgentHelper implementation. See BackupAgent.OnBackup(Android.OS.ParcelFileDescriptor, Android.App.Backup.BackupDataOutput, Android.App.Backup.BackupDataOutput) for a description of parameter meanings.