同步适配器使用ContentObserver调用了两次

Question

所以我一直有这个问题，当我显式调用requestSync时，首先调用onPerformSync，然后在30或60秒后调用，但大部分时间是60秒，这很奇怪。我使用的是ContentObserver，这种行为只有在我使用ContentObserver时才会发生。我尝试直接从内容提供商调用requestSync，但没有触发其他onPerformSync。下面列出了我的代码摘录。

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);
    }
}

带有onPerformSync 的同步适配器

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));
    }
}

Answer 1

通过将false传递给notifyChange来修复它，它确实删除了方法的同步到网络行为，如

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