FileBackupHelper.PerformBackup Method

Reference

Definition

Namespace:: Android.App.Backup

Assembly:: Mono.Android.dll

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

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.

[Android.Runtime.Register("performBackup", "(Landroid/os/ParcelFileDescriptor;Landroid/app/backup/BackupDataOutput;Landroid/os/ParcelFileDescriptor;)V", "GetPerformBackup_Landroid_os_ParcelFileDescriptor_Landroid_app_backup_BackupDataOutput_Landroid_os_ParcelFileDescriptor_Handler")]
public virtual void PerformBackup (Android.OS.ParcelFileDescriptor? oldState, Android.App.Backup.BackupDataOutput? data, Android.OS.ParcelFileDescriptor? newState);

[<Android.Runtime.Register("performBackup", "(Landroid/os/ParcelFileDescriptor;Landroid/app/backup/BackupDataOutput;Landroid/os/ParcelFileDescriptor;)V", "GetPerformBackup_Landroid_os_ParcelFileDescriptor_Landroid_app_backup_BackupDataOutput_Landroid_os_ParcelFileDescriptor_Handler")>]
abstract member PerformBackup : Android.OS.ParcelFileDescriptor * Android.App.Backup.BackupDataOutput * Android.OS.ParcelFileDescriptor -> unit
override this.PerformBackup : Android.OS.ParcelFileDescriptor * Android.App.Backup.BackupDataOutput * Android.OS.ParcelFileDescriptor -> unit

Parameters

oldState: ParcelFileDescriptor

An open, read-only 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: BackupDataOutput

An open, read/write BackupDataOutput pointing to the backup data destination. Typically the application will use backup helper classes to write to this file.

newState: ParcelFileDescriptor

An open, read/write 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.

Implements

PerformBackup(ParcelFileDescriptor, BackupDataOutput, ParcelFileDescriptor)

Attributes: RegisterAttribute

Remarks

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 BackupAgentHelper implementation. See android.app.backup.BackupAgent#onBackup(ParcelFileDescriptor, BackupDataOutput, ParcelFileDescriptor) for a description of parameter meanings.

Java documentation for android.app.backup.FileBackupHelper.performBackup(android.os.ParcelFileDescriptor, android.app.backup.BackupDataOutput, android.os.ParcelFileDescriptor).

Portions of this page are modifications based on work created and shared by the Android Open Source Project and used according to terms described in the Creative Commons 2.5 Attribution License.

Applies to