ios - 方向改变后之前的 ViewController 的屏幕截图

Question

我完全实现了这篇文章中描述的内容: Send Screenshot of ViewController to other ViewController

但是在“ProfileViewController”中更改方向后我遇到了问题。我试图获取“ViewController”的屏幕截图，但我只是获取了先前方向的 View 图像。

我尝试过类似的方法，但似乎没有任何帮助:

override func viewWillTransitionToSize(size: CGSize, withTransitionCoordinator coordinator: UIViewControllerTransitionCoordinator) {

    coordinator.animateAlongsideTransition(nil, completion: { (context : UIViewControllerTransitionCoordinatorContext!) -> Void in
        var viewController = self.navigationController!.viewControllers[0] as! UIViewController

        viewController.view.setNeedsDisplay()
        viewController.view.setNeedsLayout()
        viewController.view.layoutIfNeeded()

        self.backgroundImage = viewController.getImageDump()
    })

    super.viewWillTransitionToSize(size, withTransitionCoordinator: coordinator)
}

“getImageDump”是 UIViewController 上的扩展方法:

func getImageDump() -> UIImage {
    var size = view.bounds.size
    UIGraphicsBeginImageContextWithOptions(size, true, 0);
    view.layer.renderInContext(UIGraphicsGetCurrentContext())
    var image = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();

    return image
}

编辑:已经修复；只需手动设置 View Controller 的大小。所以而不是

        viewController.view.setNeedsDisplay()
        viewController.view.setNeedsLayout()
        viewController.view.layoutIfNeeded()

就这么做

        viewController.view.frame.size = size

Answer 1

使用快照代替

- (UIView *)snapshotViewAfterScreenUpdates:(BOOL)afterUpdates;