MFMailComposeViewController崩溃

Question

所以我运行下面的代码来呈现邮件表单，它就崩溃了。我现在已经没想到了。任何人吗？

代码：

Class mailClass = (NSClassFromString(@"MFMailComposeViewController"));

if (mailClass != nil && [mailClass canSendMail])
{
    MFMailComposeViewController *picker = [[MFMailComposeViewController alloc] init];
    picker.mailComposeDelegate = self;

    [picker setSubject:@"Subject"];

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

但它崩溃了

-[UIDeviceRGBColor shadowOffset]: unrecognized selector sent to instance 0xc135710  


0   CoreFoundation                      0x02c2f1e4 __exceptionPreprocess + 180
1   libobjc.A.dylib                     0x028f98e5 objc_exception_throw + 44
2   CoreFoundation                      0x02ccc243 -[NSObject(NSObject) doesNotRecognizeSelector:] + 275
3   CoreFoundation                      0x02c1f50b ___forwarding___ + 1019
4   CoreFoundation                      0x02c1f0ee _CF_forwarding_prep_0 + 14
5   UIKit                               0x014763fe -[UINavigationItemView _currentTextShadowOffsetForBarStyle:] + 132
6   UIKit                               0x014766b2 -[UINavigationItemView _updateLabelContents] + 396
7   UIKit                               0x01476ef1 -[UINavigationItemView _titleSize] + 51
8   UIKit                               0x01476806 -[UINavigationItemView _labelFrame] + 80
9   UIKit                               0x01475f60 -[UINavigationItemView initWithNavigationItem:] + 416
10  UIKit                               0x0144ad5a -[UINavigationItem _defaultTitleView] + 116
11  UIKit                               0x01447808 -[UINavigationItem _addDefaultTitleViewToNavigationBarIfNecessary] + 50
12  UIKit                               0x01447eb2 -[UINavigationItem setTitle:] + 212
13  MessageUI                           0x0073ac96 -[MFMailComposeInternalViewController viewDidLoad] + 593
14  UIKit                               0x014cb33d -[UIViewController loadViewIfRequired] + 696  

注意：我的班级是MFMailComposeViewControllerDelegate，我确实实现了所需的方法。

- (void)mailComposeController:(MFMailComposeViewController*)controller
          didFinishWithResult:(MFMailComposeResult)result error:(NSError*)error

Answer 1

我的错误。它是由使用外观代理引起的，但后来没有顶部导航栏。

所以我设置了 [UINavigationBar外观] 但是我在项目期间改变了主意，没有使用默认导航的UI。