Question

我正在尝试使用BroadcastReceiver在数据库服务器发生更改时触发SyncAdapter（使用GCM）。

当告知接收方开始同步过程时，我收到以下错误

ContentResolver.requestSync(accounts[0], AUTHORITY, null);

这就是我的BroadcastReceiver的样子

public class GcmBroadcastReceiver extends BroadcastReceiver {

    private static final String TAG = "GcmBroadcastReceiver";

    public static final String AUTHORITY = TournamentContract.CONTENT_AUTHORITY;
    public static final String ACCOUNT_TYPE = TournamentContract.CONTENT_AUTHORITY;
    public static final String ACCOUNT = "default_account";

    // Incoming Intent key for extended data
    public static final String KEY_SYNC_REQUEST = "com.example.android.datasync.KEY_SYNC_REQUEST";
    public static final String MESSAGE_TYPE = "gcm";

    @Override
    public void onReceive(Context context, Intent intent) {
        Log.i(TAG, "onReceive: here");
        // Get a GCM object instance
        GoogleCloudMessaging gcm =
                GoogleCloudMessaging.getInstance(context);

        // Get the type of GCM message
        String messageType = gcm.getMessageType(intent);
        /*
         * Test the message type and examine the message contents.
         * Since GCM is a general-purpose messaging system, you
         * may receive normal messages that don't require a sync
         * adapter run.
         * The following code tests for a a boolean flag indicating
         * that the message is requesting a transfer from the device.
         */
        if (MESSAGE_TYPE.equals(messageType) && intent.getBooleanExtra(KEY_SYNC_REQUEST, true)) {
            AccountManager am = AccountManager.get(context);
            Account[] accounts = am.getAccountsByType(ACCOUNT_TYPE);

            if (accounts.length == 0) {
                // todo create account if not already there
            }

            /*
             * Signal the framework to run your sync adapter. Assume that
             * app initialization has already created the account.
             */
            ContentResolver.requestSync(accounts[0], AUTHORITY, null);
        }
    }
}

我确信我的SyncAdapter工作正常，因为我没有发现周期性同步存在任何问题。

您认为我如何解决这个问题？

提前谢谢！：d

Answer 1

你没有发布实际的错误，所以很难说其他什么可能是错的，但肯定有一件事是错的：

requestSync(Account, String, Bundle)的extras参数不得为null。

如果您查看来源，则会明确检查extras的{{1}}值。

以下是ContentResolver.java

的相关代码片段

null

因此，如果public static void requestSync(Account account, String authority, Bundle extras) { requestSyncAsUser(account, authority, UserHandle.myUserId(), extras); } public static void requestSyncAsUser(Account account, String authority, int userId, Bundle extras) { if (extras == null) { throw new IllegalArgumentException("Must specify extras."); } requestSync为requestSyncAsUser，您可以看到IllegalArgumentException来电extras会引发Bundle。

如果你没有任何额外的东西要通过，你应该通过Bundle.EMPTY，如下：

null

使用BroadcastReceiver启动SyncAdapter

1 个答案: