presentViewController隐藏presentingViewController

Question

有没有一种方法可以在iOS中呈现ViewController的同时保持呈现的ViewController可见？现在，动画一结束，PresentingViewController似乎就会隐藏起来。

Answer 1

使用来自UIModalPresentationStyle的值来控制这一点。

UIModalPresentationPageSheet或UIModalPresentationFormSheet将导致演示文稿在下面留下大量的演示视图控制器。

在正在显示的视图控制器上设置modalPresentationStyle

e.g

presentedViewController.modalPresentationStyle = UIModalPresentationFormSheet;

[presentingViewController presentViewController:presentedViewController animated:YES completion:nil];

Answer 2

显示：

if let popupVC = storyboard.instantiateViewControllerWithIdentifier("PopupVC") as? PopupVC
    {
        var frame = UIScreen.mainScreen().bounds
        frame.origin.y = frame.size.height
        overlayWindow = UIWindow(frame: frame)

        popupVC.overlayWindow = overlayWindow
        overlayWindow.windowLevel = UIWindowLevelAlert
        overlayWindow.rootViewController = popupVC

        overlayWindow.makeKeyAndVisible()

        UIView.animateWithDuration(0.3, animations:
        {
            self.overlayWindow.frame.origin.y = 0
        })
    }

在PopupVC中隐藏

 if let window = overlayWindow
    {
        UIView.animateWithDuration(0.3, animations: {
            window.frame.origin.y = window.frame.height
        }, completion: { (finished) -> Void in
            self.overlayWindow = nil
        })
    }