Question

如果1x图像是100 * 100那么

2x图像是200 * 200

3x图像是300 * 300

什么是r4维度应该是xxx * xxx

没有关于此的文件。

供参考：

它不是关于启动屏幕图像...图像可以是任何像后退按钮等...

Answer 1

The answer isn't that straight forward.
The important thing to remember is that different iPhone models would automatically use different images from the imageset. The resolution of iPhone-A is not always a simple multiplication of iPhone-B, so the size of image-A can't always be a simple multiplication of image-B.

Here is a table showing the image automatically selected from x.imageset for each iPhone:
         iPhone Model | ScreenSize | Ratio | x.ImageSet
         -------------|------------|-------|----------------
            XS Max    | 1242-2688  | 0.46  | 3x
            X,XS      | 1125-2436  | 0.46  | 3x
            XR        |  828-1792  | 0.46  | 2x
            6,6s,7,8+ | 1242-2208  | 0.56  | 3x
            6,6s,7,8  |  750-1334  | 0.66  | 2x 
            5,5s      |  640-1136  | 0.56  | R4

As the table shows the same image is selected for multiple screen sizes and multiple aspect ratios, that can lead to a bit of a mess...
Thats where the Content Mode property of the view showing the image comes in handy. It decides how the image will stretch inside its boundaries (LaunchScreen image boundaries are the screen size, Back button boundaries are the ImageView size).

If the Content Mode = Aspect Fill
Then the selected image from the imageset will resize its width to be exactly as the boundary width and the height will also change to maintain the original image aspect ratio - its top and bottom edges will be hidden because they exceeded the boundary or will not reach the boundary at all.

Other Content Modes will have other effects on the image. Take a look: Understanding How Images Are Scaled

1x vs r4或2x vs r4或3x vs r4之间有什么区别？

1 个答案: