ios - 使用 segue 传递 UIImage

Question

我想在带有 segue 的两个 View 之间传递一个 UIImage。问题是我的 UIImage 在第二个 View Controller 中显示为白色。

继续:

var screenShot = UIImage()

override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
    if (segue.identifier == "screenshotEmbed") {
        let svc = segue.destinationViewController as! screenshotViewController
        svc.toPass = self.screenshot
    }

第二个 View Controller :

class screenshotViewController: UIViewController {

@IBOutlet var screenshotView: UIImageView!
var toPass = UIImage()

override func viewDidLoad() {
    super.viewDidLoad()
    self.screenshotView.image = self.toPass        
}

我的 UIImage 只是一个截图，这里是函数:

func captureScreen() -> UIImage {
    var window: UIWindow? = UIApplication.sharedApplication().keyWindow
    window = UIApplication.sharedApplication().windows[0]
    UIGraphicsBeginImageContextWithOptions(window!.frame.size, window!.opaque, 0.0)
    window!.layer.renderInContext(UIGraphicsGetCurrentContext()!)
    let image = UIGraphicsGetImageFromCurrentImageContext()
    UIGraphicsEndImageContext()
    return image;
}

编辑。按钮上的屏幕截图存储:

@IBAction func photoAction(sender: AnyObject) {
    self.screenShot = captureScreen()
}

我已经尝试了很多东西，但仍然是空白(不是空的，因为内存地址很好)。

Answer 1

不确定您的 screenshotImage 对象是否有 Image。

我试过下面的代码，它工作正常。

import UIKit

class ViewController: UIViewController {

    override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
        if (segue.identifier == "screenshotEmbed") {
            let svc = segue.destinationViewController as! ScreenshotViewController
            svc.toPass = captureScreen()
        }
    }

    func captureScreen() -> UIImage {
        var window: UIWindow? = UIApplication.sharedApplication().keyWindow
        window = UIApplication.sharedApplication().windows[0]
        UIGraphicsBeginImageContextWithOptions(window!.frame.size, window!.opaque, 0.0)
        window!.layer.renderInContext(UIGraphicsGetCurrentContext()!)
        let image = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()
        return image;
    }

}

此代码的结果:

项目 Sample了解更多信息。