Swift UIImageView Stretched Aspect

Question

UIImageView错误地渲染图像的大小.使用Scale Aspect Fit,如果UIImageView是正方形,则图像是正确的宽高比,在图像未填充的区域中具有透明度.

//Image is Square & Correct Size
var imageView = UIImageView(frame: CGRectMake(0, 50, 320, 320))
imageView.clipsToBounds = true
imageView.contentMode = UIViewContentMode.ScaleAspectFit

//Image is Rectangle & Incorrect Size
var imageView = UIImageView(frame: CGRectMake(0, 50, 320, 450))
imageView.clipsToBounds = true
imageView.contentMode = UIViewContentMode.ScaleAspectFit

UIImageView需要触摸边缘并在屏幕的顶部和底部具有透明空间,并且内部图像需要保持其原始比率而不是拉伸更高.我附上了两张UIImageView内部图像渲染图像.

Answer 1

我在UIImageView中添加了一个自动调整遮罩,它现在显示正确的比例.

imageView.autoresizingMask = UIViewAutoresizing.FlexibleBottomMargin | UIViewAutoresizing.FlexibleHeight | UIViewAutoresizing.FlexibleRightMargin | UIViewAutoresizing.FlexibleLeftMargin | UIViewAutoresizing.FlexibleTopMargin | UIViewAutoresizing.FlexibleWidth
imageView.contentMode = UIViewContentMode.ScaleAspectFit

这个答案帮助了我:捕获的照片被AVCaptureSession sessionPreset = AVCaptureSessionPresetPhoto拉伸,因为我使用的是通过手机摄像头拍摄的图像.

Answer 2

Swift 3版本的代码:

imageView.autoresizingMask = [.flexibleWidth, .flexibleHeight, .flexibleBottomMargin, .flexibleRightMargin, .flexibleLeftMargin, .flexibleTopMargin]
imageView.contentMode = .scaleAspectFit // OR .scaleAspectFill
imageView.clipsToBounds = true

Answer 3

我遇到了同样的问题,为我修复的是确保在设置内容模式后设置imageView图像.即:

    self.imageView.contentMode = UIViewContentMode.ScaleAspectFit
    self.imageView.image = imageChosen

干杯

Answer 4

这是预期的行为UIViewContentMode.ScaleAspectFit.来自文档:

UIViewContentModeScaleAspectFit

通过保持纵横比来缩放内容以适合视图大小的选项.视图边界的任何剩余区域都是透明的.

从您描述的所需内容看来 UIViewContentMode.ScaleAspectFill

UIViewContentModeScaleAspectFill

缩放内容以填充视图大小的选项.可以剪裁内容的某些部分以填充视图的边界.