Ios AFJSONRequestOperation，如果操作成功，则更新UI

我使用AFNetworking将数据发送到remove web服务，具有以下块：

self.operation = [AFJSONRequestOperation JSONRequestOperationWithRequest:request success:^(NSURLRequest *request, NSHTTPURLResponse *response, id JSON) {

    [self updateAfterPost];


} failure:^(NSURLRequest *request, NSHTTPURLResponse *response, NSError *error, id jsonObject) {
    [handle error]
}];

- (void)updateAfterPost
{
    if ([AppController sharedAppController].currentUser.twitterAccount.crossPost.boolValue == YES) {
        [self postToTwitter];
    }
    [other things that should update the UI]
}

- (void)postToTwitter
{
    ACAccountType *accountType = [self.accountStore accountTypeWithAccountTypeIdentifier:ACAccountTypeIdentifierTwitter];
    [self.accountStore requestAccessToAccountsWithType:accountType options:nil completion:^(BOOL granted, NSError *error) {
        if (granted == YES) {            
            if ([self.twitterAccounts count] > 0) {
                ACAccount *twitterAccount = [self.twitterAccounts objectAtIndex:[AppController sharedAppController].currentUser.twitterAccount.accountId.integerValue];
                NSDictionary *message = @{@"status":self.postTextField.text};
                NSURL *requestURL = [NSURL URLWithString:@"http://api.twitter.com/1/statuses/update.json"];
                SLRequest *postRequest = [SLRequest requestForServiceType:SLServiceTypeTwitter requestMethod:SLRequestMethodPOST URL:requestURL parameters:message];
                postRequest.account = twitterAccount;
                [postRequest performRequestWithHandler:^(NSData *responseData, NSHTTPURLResponse *urlResponse, NSError *error) {
                 }];
            }
        }
    }];
}

posttowitter

操作会导致以下警告（如果我取消对方法的注释，则不会发出警告）：

我不知道怎么解决它。我在成功块中尝试了

NSNotification

，但没有成功（通知可能也在后台线程中发送）。有什么想法或建议吗

更新

---

我还尝试了

[self-performSelectorOnMainThread:@selector（updateAfterPost）with-object:nil waitUntilDone:YES]

在任意队列上调用

requestAccessToAccountsWithType

的完成块，因此您不能调用其中的UI元素（postTextField）

您应该使用dispatch\u async call包装代码：

- (void)postToTwitter
{
    ACAccountType *accountType = [self.accountStore accountTypeWithAccountTypeIdentifier:ACAccountTypeIdentifierTwitter];
    [self.accountStore requestAccessToAccountsWithType:accountType options:nil completion:^(BOOL granted, NSError *error) {
        dispatch_async(dispatch_get_main_queue(), ^{
        if (granted == YES) {            
            if ([self.twitterAccounts count] > 0) {
                ACAccount *twitterAccount = [self.twitterAccounts objectAtIndex:[AppController sharedAppController].currentUser.twitterAccount.accountId.integerValue];
                NSDictionary *message = @{@"status":self.postTextField.text};
                NSURL *requestURL = [NSURL URLWithString:@"http://api.twitter.com/1/statuses/update.json"];
                SLRequest *postRequest = [SLRequest requestForServiceType:SLServiceTypeTwitter requestMethod:SLRequestMethodPOST URL:requestURL parameters:message];
                postRequest.account = twitterAccount;
                [postRequest performRequestWithHandler:^(NSData *responseData, NSHTTPURLResponse *urlResponse, NSError *error) {
                 }];
            }
        }
        });  
    }];
}

---

小注：我必须为我的

self.postTestField.text

创建一个块变量，并在块中使用该变量。

- (void)postToTwitter
{
    ACAccountType *accountType = [self.accountStore accountTypeWithAccountTypeIdentifier:ACAccountTypeIdentifierTwitter];
    [self.accountStore requestAccessToAccountsWithType:accountType options:nil completion:^(BOOL granted, NSError *error) {
        dispatch_async(dispatch_get_main_queue(), ^{
        if (granted == YES) {            
            if ([self.twitterAccounts count] > 0) {
                ACAccount *twitterAccount = [self.twitterAccounts objectAtIndex:[AppController sharedAppController].currentUser.twitterAccount.accountId.integerValue];
                NSDictionary *message = @{@"status":self.postTextField.text};
                NSURL *requestURL = [NSURL URLWithString:@"http://api.twitter.com/1/statuses/update.json"];
                SLRequest *postRequest = [SLRequest requestForServiceType:SLServiceTypeTwitter requestMethod:SLRequestMethodPOST URL:requestURL parameters:message];
                postRequest.account = twitterAccount;
                [postRequest performRequestWithHandler:^(NSData *responseData, NSHTTPURLResponse *urlResponse, NSError *error) {
                 }];
            }
        }
        });  
    }];
}