iOS6的社會結構帶來了無帳戶警報

Question

類似iOS 6 Social framework not going to settings or no alert但我試圖用SLRequest：

我試圖彈出警告「沒有Facebook的帳戶」當用戶沒有登錄到Facebook在設置。我發現警報在出現SLComposeViewController之後出現，而不是出現在if語句中。

if([SLComposeViewController isAvailableForServiceType:SLServiceTypeFacebook]) 
{ 
    SLComposeViewController *controller = [SLComposeViewController composeViewControllerForServiceType:SLServiceTypeFacebook]; 

    //setup controller and callback code 

    [self presentViewController:controller animated:YES completion:nil]; 
} 

不過，我試圖用SLRequest，我不希望出現的SLComposeViewController，而是清查賬目後，彈出警報。我的代碼是在這裏：

- (void)postImageFB 
{ 
if([SLComposeViewController isAvailableForServiceType:SLServiceTypeFacebook]) { 
    NSLog(@"can post"); 
} else { 
    NSLog(@"cant post"); 
} 

ACAccountStore *accountStore = [[ACAccountStore alloc] init]; 

ACAccountType *accountType = [accountStore accountTypeWithAccountTypeIdentifier:ACAccountTypeIdentifierFacebook]; 

NSArray *accountsArray = [accountStore accountsWithAccountType:accountType]; 
NSLog(@"accounts: %i", [accountsArray count]); 

// Is it possible to popup the alert here if accounts = 0? 

NSDictionary *options = @{ ACFacebookAppIdKey: @"123456789", ACFacebookPermissionsKey: @[@"publish_stream"], ACFacebookAudienceKey: ACFacebookAudienceFriends }; 

[accountStore requestAccessToAccountsWithType:accountType options:options completion:^(BOOL granted, NSError *error) { 
    if(granted) { 

     NSArray *accountsArray = [accountStore accountsWithAccountType:accountType]; 

     if ([accountsArray count] > 0) { 

      ACAccount *facebookAccount = [accountsArray objectAtIndex:0]; 

      NSDictionary *parameters = @{@"message": @"testing"}; 

      SLRequest *facebookRequest = [SLRequest requestForServiceType:SLServiceTypeFacebook 
                  requestMethod:SLRequestMethodPOST 
                     URL:[NSURL URLWithString:@"https://graph.facebook.com/me/photos"] 
                   parameters:parameters]; 

      [facebookRequest addMultipartData: [self getImageDataFromPlistWithFilename:@"image1.png"] 
            withName:@"source" 
             type:@"multipart/form-data" 
            filename:@"TestImage"]; 

      facebookRequest.account = facebookAccount; 

      [facebookRequest performRequestWithHandler:^(NSData *responseData, NSHTTPURLResponse *urlResponse, NSError *error) 
      { 
       if (error) { 
        NSLog(@"%@",error.description); 
       } else { 
        NSLog(@"responedata:%@", [[NSString alloc] initWithData:responseData encoding:NSUTF8StringEncoding]); 
       } 

      }]; 
     } 
    } 
}]; 

} 

Answer 1

好吧，我發現isAvailableForServiceType always returns true? 所以開始在設備上測試。

我計算過，用一種無形的SLComposeViewController彈出警報似乎是一個合適的解決辦法：

if (![SLComposeViewController isAvailableForServiceType:SLServiceTypeFacebook]) { 

    SLComposeViewController *controller = [SLComposeViewController composeViewControllerForServiceType:SLServiceTypeFacebook]; 
    controller.view.hidden = YES; 
    [self presentViewController:controller animated:NO completion:nil]; 

} else { 

    // Put posting code here: SLComposeViewController or SLRequest 

}