UIViewController 未从情节提要中呈现

Question

我在 Main.storyboard 中创建了一个 UIViewController，并尝试从 UIImagePickerController 委托方法中以编程方式呈现它。但我收到了消息：

Warning: Attempt to present <DAAnalysisViewController: 0x8b99960> on 
<DAViewController: 0x8b35300> whose view is not in the window hierarchy!

代码：

- (void)imagePickerController:(UIImagePickerController *)picker 
didFinishPickingMediaWithInfo:(NSDictionary *)info{

    DAAnalysisViewController *asdf = [[UIStoryboard storyboardWithName:@"Main" bundle:nil] 
   instantiateViewControllerWithIdentifier:@"1"];

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

如何从情节提要中正确呈现 UIViewController？

Answer 1

如果您的图像选择器以模态方式呈现，您可能需要先将其关闭，然后才能显示您的自定义视图控制器。像这样的：

- (void)imagePickerController:(UIImagePickerController *)picker
didFinishPickingMediaWithInfo:(NSDictionary *)info
{
    [self dismissViewControllerAnimated:YES completion:^{
        UIStoryboard *sb = [UIStoryboard storyboardWithName:@"Main" bundle:nil];

        DAAnalysisViewController *asdf = [sb instantiateViewControllerWithIdentifier:@"1"];

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