如何显示viewcontroller：UIImagePickController并将其关闭（快速）

Question

我得到了这个uiactionsheet，它在UISplitViewController的viewcontroller中加载了uipickerviewcontroller

这是一个UIsplitviewcontroller，此代码位于detailview上，从masterview调用detailview

但是，当我尝试加载“单击它”时，它会警告我并且不再继续

   func actionSheet(actionSheet: UIActionSheet!, clickedButtonAtIndex buttonIndex: Int){
    var imagePicker = UIImagePickerController()
    imagePicker.delegate = self

    switch buttonIndex{

    case 0:
        imagePicker.sourceType = UIImagePickerControllerSourceType.SavedPhotosAlbum
        imagePicker.allowsEditing = true
        imagePicker.delegate = self
        NSLog("Vælg fra Biblioteket");
        break;
    case 1:
        imagePicker.sourceType = UIImagePickerControllerSourceType.Camera
        imagePicker.allowsEditing = true
        imagePicker.delegate = self
        NSLog("Vælg Kamera");
        break;
    default:
        NSLog("Default");
        break;
    }
    self.presentViewController(imagePicker, animated: true, completion: nil) // this is the problem 
}

警告是这样的：警告：尝试在已经显示的内容上显示（空）

我如何使用它：self.showDeatilViewController（imagePicker，true）它显示出来，但是我根本无法将其关闭

这就是我认为它将被驳回的方式

    func imagePickerControllerDidCancel(picker: UIImagePickerController) {

    picker.dismissViewControllerAnimated(true, completion: nil)
}

如果我在viewDidLoad中运行此代码，则可以工作

        var imagePickerController = UIImagePickerController()
    imagePickerController.delegate = self
    imagePickerController.sourceType = UIImagePickerControllerSourceType.SavedPhotosAlbum
    imagePickerController.allowsEditing = true
    self.presentViewController(imagePickerController, animated: true, completion: { imageP in

    })

我发现如果我写这个：

        self.presentedViewController?.presentViewController(imagePicker, animated: true, completion: nil)

它显示并关闭？！？！

Answer 1

我已经开始工作了……有人提醒我，8.0 IOS在打开应用程序的照片库等时出现了一个错误。所以我将其放在这样的主队列中

dispatch_async(dispatch_get_main_queue()){
        imagePicker.delegate = self
        self.presentViewController(imagePicker, animated: true, completion: nil)
    }

现在就可以了！

稍有延迟，但有效