SharedPreferencesBackupHelper Class

Reference

Definition

Namespace:: Android.App.Backup

Assembly:: Mono.Android.dll

Important

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A helper class that can be used in conjunction with android.app.backup.BackupAgentHelper to manage the backup of android.content.SharedPreferences.

[Android.Runtime.Register("android/app/backup/SharedPreferencesBackupHelper", DoNotGenerateAcw=true)]
public class SharedPreferencesBackupHelper : Android.App.Backup.FileBackupHelperBase, Android.App.Backup.IBackupHelper, IDisposable, Java.Interop.IJavaPeerable

[<Android.Runtime.Register("android/app/backup/SharedPreferencesBackupHelper", DoNotGenerateAcw=true)>]
type SharedPreferencesBackupHelper = class
    inherit FileBackupHelperBase
    interface IBackupHelper
    interface IJavaObject
    interface IDisposable
    interface IJavaPeerable

Inheritance: Object

Object

FileBackupHelperBase
SharedPreferencesBackupHelper

Attributes: RegisterAttribute

Implements: IBackupHelper IJavaObject IJavaPeerable IDisposable

Remarks

A helper class that can be used in conjunction with android.app.backup.BackupAgentHelper to manage the backup of android.content.SharedPreferences. Whenever a backup is performed, it will back up all named shared preferences that have changed since the last backup operation.

To use this class, the application's backup agent class should extend android.app.backup.BackupAgentHelper. Then, in the agent's BackupAgent#onCreate() method, an instance of this class should be allocated and installed as a backup/restore handler within the BackupAgentHelper framework. For example, an agent supporting backup and restore for an application with two groups of android.content.SharedPreferences data might look something like this:

import android.app.backup.BackupAgentHelper;
            import android.app.backup.SharedPreferencesBackupHelper;

            public class MyBackupAgent extends BackupAgentHelper {
                // The names of the SharedPreferences groups that the application maintains.  These
                // are the same strings that are passed to {@link Context#getSharedPreferences(String, int)}.
                static final String PREFS_DISPLAY = "displayprefs";
                static final String PREFS_SCORES = "highscores";

                // An arbitrary string used within the BackupAgentHelper implementation to
                // identify the SharedPreferenceBackupHelper's data.
                static final String MY_PREFS_BACKUP_KEY = "myprefs";

                // Allocate a helper and install it.
                public void onCreate() {
                    SharedPreferencesBackupHelper helper =
                            new SharedPreferencesBackupHelper(this, PREFS_DISPLAY, PREFS_SCORES);
                    addHelper(MY_PREFS_BACKUP_KEY, helper);
                }
            }

No further implementation is needed; the BackupAgentHelper mechanism automatically dispatches the BackupAgent#onBackup(android.os.ParcelFileDescriptor, BackupDataOutput, android.os.ParcelFileDescriptor) BackupAgent.onBackup() and BackupAgent#onRestore(BackupDataInput, int, android.os.ParcelFileDescriptor) BackupAgent.onRestore() callbacks to the SharedPreferencesBackupHelper as appropriate.

Java documentation for android.app.backup.SharedPreferencesBackupHelper.

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.

Constructors

SharedPreferencesBackupHelper(Context, String[])	Construct a helper for backing up and restoring the `android.content.SharedPreferences` under the given names.
SharedPreferencesBackupHelper(IntPtr, JniHandleOwnership)	A constructor used when creating managed representations of JNI objects; called by the runtime.

Properties

Class	Returns the runtime class of this `Object`. (Inherited from Object)
Handle	The handle to the underlying Android instance. (Inherited from Object)
JniIdentityHashCode	(Inherited from Object)
JniPeerMembers
PeerReference	(Inherited from Object)
ThresholdClass	This API supports the Mono for Android infrastructure and is not intended to be used directly from your code.
ThresholdType	This API supports the Mono for Android infrastructure and is not intended to be used directly from your code.

Methods

Clone()	Creates and returns a copy of this object. (Inherited from Object)
Dispose()	(Inherited from Object)
Dispose(Boolean)	(Inherited from Object)
Equals(Object)	Indicates whether some other object is "equal to" this one. (Inherited from Object)
GetHashCode()	Returns a hash code value for the object. (Inherited from Object)
JavaFinalize()	Called by the garbage collector on an object when garbage collection determines that there are no more references to the object. (Inherited from Object)
Notify()	Wakes up a single thread that is waiting on this object's monitor. (Inherited from Object)
NotifyAll()	Wakes up all threads that are waiting on this object's monitor. (Inherited from Object)
PerformBackup(ParcelFileDescriptor, BackupDataOutput, ParcelFileDescriptor)	Backs up the configured `android.content.SharedPreferences` groups.
RestoreEntity(BackupDataInputStream)	Restores one entity from the restore data stream to its proper shared preferences file store.
SetHandle(IntPtr, JniHandleOwnership)	Sets the Handle property. (Inherited from Object)
ToArray<T>()	(Inherited from Object)
ToString()	Returns a string representation of the object. (Inherited from Object)
UnregisterFromRuntime()	(Inherited from Object)
Wait()	Causes the current thread to wait until it is awakened, typically by being <em>notified</em> or <em>interrupted</em>. (Inherited from Object)
Wait(Int64, Int32)	Causes the current thread to wait until it is awakened, typically by being <em>notified</em> or <em>interrupted</em>, or until a certain amount of real time has elapsed. (Inherited from Object)
Wait(Int64)	Causes the current thread to wait until it is awakened, typically by being <em>notified</em> or <em>interrupted</em>, or until a certain amount of real time has elapsed. (Inherited from Object)
WriteNewStateDescription(ParcelFileDescriptor)	Called by BackupAgentHelper after a restore operation to write the backup state file corresponding to the data as processed by the helper.

Explicit Interface Implementations

IJavaPeerable.Disposed()	(Inherited from Object)
IJavaPeerable.DisposeUnlessReferenced()	(Inherited from Object)
IJavaPeerable.Finalized()	(Inherited from Object)
IJavaPeerable.JniManagedPeerState	(Inherited from Object)
IJavaPeerable.SetJniIdentityHashCode(Int32)	(Inherited from Object)
IJavaPeerable.SetJniManagedPeerState(JniManagedPeerStates)	(Inherited from Object)
IJavaPeerable.SetPeerReference(JniObjectReference)	(Inherited from Object)

Extension Methods

PerformBackupAsync(IBackupHelper, ParcelFileDescriptor, BackupDataOutput, ParcelFileDescriptor)
JavaCast<TResult>(IJavaObject)	Performs an Android runtime-checked type conversion.
JavaCast<TResult>(IJavaObject)
GetJniTypeName(IJavaPeerable)

Applies to

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