AbstractThreadedSyncAdapter

Class Overview

An abstract implementation of a SyncAdapter that spawns a thread to invoke a sync operation. If a sync operation is already in progress when a startSync() request is received then an error will be returned to the new request and the existing request will be allowed to continue. When a startSync() is received and there is no sync operation in progress then a thread will be started to run the operation and onPerformSync(Account, Bundle, String, ContentProviderClient, SyncResult) will be invoked on that thread. If a cancelSync() is received that matches an existing sync operation then the thread that is running that sync operation will be interrupted, which will indicate to the thread that the sync has been canceled.

In order to be a sync adapter one must extend this class, provide implementations for the abstract methods and write a service that returns the result of getSyncAdapterBinder() in the service's onBind(android.content.Intent) when invoked with an intent with action android.content.SyncAdapter. This service must specify the following intent filter and metadata tags in its AndroidManifest.xml file

   <intent-filter>
     <action android:name="android.content.SyncAdapter" />
   </intent-filter>
   <meta-data android:name="android.content.SyncAdapter"
             android:resource="@xml/syncadapter" />
 

 <sync-adapter xmlns:android="http://schemas.android.com/apk/res/android"
    android:contentAuthority="authority"
    android:accountType="accountType"
    android:userVisible="true|false"
    android:supportsUploading="true|false"
    android:allowParallelSyncs="true|false"
    android:isAlwaysSyncable="true|false"
    android:syncAdapterSettingsAction="ACTION_OF_SETTINGS_ACTIVITY"
 />
 

• The android:contentAuthority and android:accountType attributes indicate which content authority and for which account types this sync adapter serves.
• android:userVisible defaults to true and controls whether or not this sync adapter shows up in the Sync Settings screen.
• android:supportsUploading defaults to true and if true an upload-only sync will be requested for all syncadapters associated with an authority whenever that authority's content provider does a notifyChange(android.net.Uri, android.database.ContentObserver, boolean) with syncToNetwork set to true.
• android:allowParallelSyncs defaults to false and if true indicates that the sync adapter can handle syncs for multiple accounts at the same time. Otherwise the SyncManager will wait until the sync adapter is not in use before requesting that it sync an account's data.
• android:isAlwaysSyncable defaults to false and if true tells the SyncManager to intialize the isSyncable state to 1 for that sync adapter for each account that is added.
• android:syncAdapterSettingsAction defaults to null and if supplied it specifies an Intent action of an activity that can be used to adjust the sync adapter's sync settings. The activity must live in the same package as the sync adapter.

Summary

[Expand] Inherited Methods

From class java.lang.Object Object clone() Creates and returns a copy of this Object. boolean equals(Object o) Compares this instance with the specified object and indicates if they are equal. void finalize() Invoked when the garbage collector has detected that this instance is no longer reachable. final Class<?> getClass() Returns the unique instance of Class that represents this object's class. int hashCode() Returns an integer hash code for this object. final void notify() Causes a thread which is waiting on this object's monitor (by means of calling one of the wait() methods) to be woken up. final void notifyAll() Causes all threads which are waiting on this object's monitor (by means of calling one of the wait() methods) to be woken up. String toString() Returns a string containing a concise, human-readable description of this object. final void wait() Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object. final void wait(long millis, int nanos) Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object or until the specified timeout expires. final void wait(long millis) Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object or until the specified timeout expires.