使用ContentObserver调用两次同步适配器

时间:2016-05-02 20:55:15

标签: java android asynchronous android-syncadapter contentobserver

所以我一直遇到这个问题,当我明确调用requestSync时,首先调用onPerformSync,其次是30或60秒后,但大多数是60秒,这很奇怪。我正在使用ContentObserver,这种行为只发生在我使用ContentObserver时。我尝试直接从我的内容提供商调用requestSync,并且没有触发其他onPerformSync。我的代码摘录列在下面。

提供商调用notifyChange

@Nullable
@Override
public Uri insert(@NonNull Uri uri, ContentValues values) {
    Log.d(LOG_TAG, "Inserting with uri " + uri + " with values " + values.toString());
    SQLiteDatabase db = mOpenHelper.getWritableDatabase();
    int match = sUriMatcher.match(uri);

    ....

    // This direct requestSync call does not trigger extra syncs
    //Bundle extras = new Bundle();
    //extras.putString(SyncAdapter.CHANGED_URI, uri.toString());
    //getContext().getContentResolver().requestSync(SyncAccount.getAccount(), Contract.CONTENT_AUTHORITY, extras);

    getContext().getContentResolver().notifyChange(contentUri, null);

    return contentUri;
}

带onChange的ContentObserver

public class TableObserver extends ContentObserver {

    private final static String LOG_TAG = TableObserver.class.getSimpleName();

    private final Account mAccount;

    public TableObserver(Handler handler, Account account) {
        super(handler);

        mAccount = account;
    }

    @Override
    public void onChange(boolean selfChange) {
        super.onChange(selfChange, null);
    }

    @Override
    public void onChange(boolean selfChange, Uri uri) {
        Log.d(LOG_TAG, "Provider changed here: " + uri.toString());
        Bundle args = new Bundle();
        args.putString(SyncAdapter.CHANGED_URI, uri.toString());

       ContentResolver.requestSync(mAccount,  Contract.CONTENT_AUTHORITY, args);
    }
}

使用onPerformSync同步适配器

public class SyncAdapter extends AbstractThreadedSyncAdapter {

    private static final String LOG_TAG = SyncAdapter.class.getSimpleName();

    public static final String CHANGED_URI = "changed_uri";

    private ContentResolver mContentResolver;

    public SyncAdapter(Context context, boolean autoInitialize) {
        super(context, autoInitialize);

        mContentResolver = context.getContentResolver();
    }

    public SyncAdapter(Context context, boolean autoInitialize, boolean allowParallelSyncs) {
        super(context, autoInitialize, allowParallelSyncs);

        mContentResolver = context.getContentResolver();
    }

    // This is automatically performed in a background thread.
    @Override
    public void onPerformSync(Account account, Bundle extras, String authority, ContentProviderClient provider, SyncResult syncResult) {
        Log.d(LOG_TAG, "Synchronizing: " + extras.get(CHANGED_URI));
    }
}

1 个答案:

答案 0 :(得分:2)

通过将false传递给notifyChange来修复它,后者确实删除了方法的同步到网络行为,如下所示:

getContext().getContentResolver().notifyChange(contentUri, null, false);