AbstractThreadedSyncAdapter
public
abstract
class
AbstractThreadedSyncAdapter
extends Object
| java.lang.Object | |
| ↳ | android.content.AbstractThreadedSyncAdapter |
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 sync request is received, an error will be
returned to the new request and the existing request will be allowed to continue.
However if there is no sync in progress then a thread will be spawned and onPerformSync(Account, Bundle, String, ContentProviderClient, SyncResult)
will be invoked on that thread.
Syncs can be cancelled at any time by the framework. For example a sync that was not
user-initiated and lasts longer than 10 minutes will be considered timed-out and cancelled.
Similarly the framework will attempt to determine whether or not an adapter is making progress
by monitoring its network activity over the course of a minute. If the network traffic over this
window is close enough to zero the sync will be cancelled. You can also request the sync be
cancelled via ContentResolver.cancelSync(Account,String) or
ContentResolver.cancelSync(SyncRequest).
A sync is cancelled by issuing a Thread.interrupt() on the syncing thread. Either
your code in onPerformSync(Account,Bundle,String,ContentProviderClient,SyncResult)
must check Thread.interrupted(), or you you must override one of
onSyncCanceled(Thread)/onSyncCanceled() (depending on whether or not
your adapter supports syncing of multiple accounts in parallel). If your adapter does not
respect the cancel issued by the framework you run the risk of your app's entire process being
killed.
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 Service.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" />
The android:resource attribute must point to a resource that looks like:
<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:contentAuthorityandandroid:accountTypeattributes indicate which content authority and for which account types this sync adapter serves. android:userVisibledefaults to true and controls whether or not this sync adapter shows up in the Sync Settings screen.android:supportsUploadingdefaults 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 aContentResolver.notifyChange(android.net.Uri,android.database.ContentObserver,boolean)with syncToNetwork set to true.android:allowParallelSyncsdefaults 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:isAlwaysSyncabledefaults to false and if true tells the SyncManager to initialize the isSyncable state to 1 for that sync adapter for each account that is added.android:syncAdapterSettingsActiondefaults 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
Constants | |
|---|---|
int |
LOG_SYNC_DETAILS
This constant was deprecated in API level 15. Private constant. May go away in the next release. |
Public constructors | |
|---|---|
AbstractThreadedSyncAdapter(Context context, boolean autoInitialize)
Creates an |
|
AbstractThreadedSyncAdapter(Context context, boolean autoInitialize, boolean allowParallelSyncs)
Creates an |
|
Public methods | |
|---|---|
Context
|
getContext()
|
final
IBinder
|
getSyncAdapterBinder()
|
abstract
void
|
onPerformSync(Account account, Bundle extras, String authority, ContentProviderClient provider, SyncResult syncResult)
Perform a sync for this account. |
void
|
onSecurityException(Account account, Bundle extras, String authority, SyncResult syncResult)
Report that there was a security exception when opening the content provider
prior to calling |
void
|
onSyncCanceled(Thread thread)
Indicates that a sync operation has been canceled. |
void
|
onSyncCanceled()
Indicates that a sync operation has been canceled. |
boolean
|
onUnsyncableAccount()
Allows to defer syncing until all accounts are properly set up. |
Inherited methods | |
|---|---|
Constants
LOG_SYNC_DETAILS
public static final int LOG_SYNC_DETAILS
This constant was deprecated
in API level 15.
Private constant. May go away in the next release.
Kernel event log tag. Also listed in data/etc/event-log-tags.
Constant Value: 2743 (0x00000ab7)
Public constructors
AbstractThreadedSyncAdapter
public AbstractThreadedSyncAdapter (Context context, boolean autoInitialize)
Creates an AbstractThreadedSyncAdapter.
| Parameters | ||
|---|---|---|
context |
Context: the Context that this is running within. |
|
autoInitialize |
boolean: if true then sync requests that have
ContentResolver.SYNC_EXTRAS_INITIALIZE set will be internally handled by
AbstractThreadedSyncAdapter by calling
ContentResolver.setIsSyncable(android.accounts.Account,String,int) with 1 if it
is currently set to
| |