使用ContentObserver调用了两次同步适配器

Question

So I have been having this problem where onPerformSync is called first when I explicitly call requestSync and secondly after 30 or 60 seconds but mostly 60 seconds, its weird. I am using a ContentObserver and this behaviour is only happening when I use a ContentObserver. I tried calling requestSync directly from my content provider and no additional onPerformSync were triggered. My code excerpts are listed below.

Provider calls 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;
}

ContentObserver with onChange

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);
    }
}

Sync adapter with onPerformSync

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));
    }
}

Answer 1

通过将false传递给notifyChange来修复它，该方法确实删除了该方法与网络行为的同步，如下所示：

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