按下按钮时截取部分截图

Question

我正在尝试通过按下按钮截取部分屏幕截图并将其保存到相机胶卷。

我有从另一个问题中找到的代码，但按下按钮会使应用程序崩溃。

// Declare the snapshot boundaries
let top: CGFloat = 100
let bottom: CGFloat = 0

// The size of the cropped image
let size = CGSize(width: view.frame.size.width, height: view.frame.size.height - top - bottom)

// Start the context
UIGraphicsBeginImageContext(size)

// we are going to use context in a couple of places
let context = UIGraphicsGetCurrentContext()!

// Transform the context so that anything drawn into it is displaced "top" pixels up

context.translateBy(x: 0, y: -top)

// Draw the view into the context (this is the snapshot)
view.layer.render(in: context)
let snapshot = UIGraphicsGetImageFromCurrentImageContext()

// End the context (this is required to not leak resources)
UIGraphicsEndImageContext()

// Save to photos
UIImageWriteToSavedPhotosAlbum(snapshot!, nil, nil, nil)

Answer 1

在此函数中使用参数调用您的屏幕截图视图：-

func imageWithView(view: UIView) -> UIImage {
     UIGraphicsBeginImageContextWithOptions(view.bounds.size, view.opaque, 0.0)
     view.layer.renderInContext(UIGraphicsGetCurrentContext()!)
     let img = UIGraphicsGetImageFromCurrentImageContext()
     UIGraphicsEndImageContext()
     return img
}