我有一个UIImageView目标是按比例缩小它通过给它一个高度或宽度。

UIImage *image = [[UIImage alloc] initWithData:[NSData dataWithContentsOfURL:[NSURL URLWithString:@"http://farm4.static.flickr.com/3092/2915896504_a88b69c9de.jpg"]]];
UIImageView *imageView = [[UIImageView alloc] initWithImage:image]; 

//Add image view
[self.view addSubview:imageView];   

//set contentMode to scale aspect to fit
imageView.contentMode = UIViewContentModeScaleAspectFit;

//change width of frame
CGRect frame = imageView.frame;
frame.size.width = 100;
imageView.frame = frame;

图像确实调整了大小,但位置不在左上方。缩放image/imageView的最佳方法是什么?我如何纠正位置?


当前回答

我使用以下代码。imageCoverView是UIView持有UIImageView

if (image.size.height<self.imageCoverView.bounds.size.height && image.size.width<self.imageCoverView.bounds.size.width)
{
    [self.profileImageView sizeToFit];
    self.profileImageView.contentMode =UIViewContentModeCenter
}
else
{
    self.profileImageView.contentMode =UIViewContentModeScaleAspectFit;
}

其他回答

这对我来说很好Swift 2.x:

imageView.contentMode = .ScaleAspectFill
imageView.clipsToBounds = true;

我觉得你可以

image.center = [[imageView window] center];

斯威夫特:

self.imageViews.contentMode = UIViewContentMode.ScaleToFill

修复容易,一旦我找到文档!

 imageView.contentMode = .scaleAspectFit

通常我在我的应用程序中使用这种方法(Swift 2。x兼容的):

// Resize UIImage
func resizeImage(image:UIImage, scaleX:CGFloat,scaleY:CGFloat) ->UIImage {
    let size = CGSizeApplyAffineTransform(image.size, CGAffineTransformMakeScale(scaleX, scaleY))
    let hasAlpha = true
    let scale: CGFloat = 0.0 // Automatically use scale factor of main screen

    UIGraphicsBeginImageContextWithOptions(size, !hasAlpha, scale)
    image.drawInRect(CGRect(origin: CGPointZero, size: size))

    let scaledImage = UIGraphicsGetImageFromCurrentImageContext()
    UIGraphicsEndImageContext()
    return scaledImage
}