ios - MFMailComposeViewController打开然后关闭

Question

我有一个MFMailComposeViewController，我相信它已正确实现。但是，当它显示在屏幕上(通过模式显示)时，它只是打开，挂起一秒钟，然后关闭并记录MFMailComposeResultCancelled
有什么想法吗？

            if ([MFMailComposeViewController canSendMail]){
                MFMailComposeViewController *composer = [[MFMailComposeViewController alloc] init];



                if( composer == nil ){
                    UIAlertView* alert_view = [[UIAlertView alloc] initWithTitle:@"message"
                                                                          message:@"You will need to setup a mail account on your device before you can send mail!"
                                                                         delegate:nil
                                                                cancelButtonTitle:@"OK"
                                                                otherButtonTitles:nil];
                    [alert_view show];
                    return;
                }else{



                composer.mailComposeDelegate = self;
                [composer setSubject:@"I have an issue"];
                [composer setMessageBody:@"" isHTML:NO];
                [composer setToRecipients:@[@"email"]];
                }


                [self presentViewController:composer animated:YES completion:^{
                    ;
                }];

编辑在日志中找到了这些
Unbalanced calls to begin/end appearance transitions for <UINavigationController: 0xcda5e90>. The operation couldn’t be completed. (Cocoa error 4097.)

Answer 1

如果上拉MFMailComposer时UI发生任何更改，则调用MFMailComposeResultCancelled。

尽管您可以更改颜色，但我必须是默认的iOS导航标题。