iphone - 我们如何在小 UIImageview 上设置大 UIImage

Question

我正在使用尺寸为 320X320 的 imagview 来显示大图像（350 X 783）。

将大图像放入图像视图时，图像看起来被挤压，压缩的东西不像质量。

我的问题是，如何将大图像制作成与原始图像一样质量的小图像？

Answer 1

您可以将图像视图设置为适当的内容模式，就像这样

        imageView.contentMode = UIViewContentModeScaleAspectFit

Answer 2

-(UIImage*)scaleToSize:(CGSize)size {
    // Create a bitmap graphics context
    // This will also set it as the current context
    UIGraphicsBeginImageContext(size);
    // Draw the scaled image in the current context
    [self drawInRect:CGRectMake(0, 0, size.width, size.height)];
    // Create a new image from current context
    UIImage* scaledImage = UIGraphicsGetImageFromCurrentImageContext();
    // Pop the current context from the stack
    UIGraphicsEndImageContext();
    // Return our new scaled image
    return scaledImage;
}

Answer 3

你可以这样做，

    UIImage* sourceImage = "yourImage";
    CGSize newSize=CGSizeMake(80,80);
    UIGraphicsBeginImageContext( newSize );
    [image drawInRect:CGRectMake(0,0,newSize.width,newSize.height)];
    UIImage* newImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();

    yourImageView.image=newImage;