SwiftUI中的图片全屏宽度

Question

I added an image to my body in a SwiftUI application and want to have that image cover the full width of the device, but not go over it.

In body , I return the image object:

var body: some View {
    Image("page-under-construction")
}

and the image shows up, however, it's too big:

I tried setting the frame: that affects the highlighted boundaries, but the image does not resize.
In combination, I played around with .aspectRatio(contentMode:) , which did not seem to have any effect on the layout.

How can I have the image be effectively 100% of the screen width?

Answer 1

The reason .aspectRatio(contentMode:) had no effect on the layout is because you did not make the image resizable with resizeable() .

Doing

var body: some View {
    Image("page-under-construction")
    .resizable()
    .aspectRatio(contentMode: .fill)
}

will cause the image to be the width of the screen, but the image's aspect ratio will not be maintained. To maintain the aspect ratio, do

var body: some View {
    Image("page-under-construction")
    .resizable()
    .aspectRatio(UIImage(named: "page-under-construction")!.size, contentMode: .fill)
}

This utilizes the .aspectRatio(aspectRatio: CGSize, contentMode: ContentMode) version of the method your original question discussed with a dummy UIImage to access the Image's original aspect ratio.

Note: The explicitly unwrapped optional ( ! ) should not be a problem unless you are unsure if the image name is a valid one from your Assets folder. See this post for a comprehensive overview on Swift optionals.

Answer 2

Did you try resizable modifier?

struct ImageView: View {
var body: some View {
    Image("turtlerock")
    .resizable()
    .aspectRatio(contentMode: .fit)
}}

Note - There are 2 content modes: .fit and .fill