Ranging from iOS 16, SwiftUI gives AnyLayout and the Format protocol for builders to create custom-made and sophisticated layouts. AnyLayout is a type-erased occasion of the format protocol. You should use AnyLayout to create a dynamic format that responds to customers’ interactions or atmosphere adjustments.
On this tutorial, you’ll discover ways to use AnyLayout to modify between vertical and horizontal format.
Utilizing AnyLayout
Let’s first create a brand new Xcode mission utilizing the App template. Identify the mission SwiftUIAnyLayout or no matter identify you like. What we’re going to construct is a straightforward demo app that switches the UI format if you faucet the stack view. The determine under reveals the UI format for various orientations.
The app initially arranges three photos vertically utilizing VStack. When a person faucets the stack view, it adjustments to a horizontal stack. With AnyLayout, you possibly can implement the format like this:
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 |
struct ContentView: View { @State personal var changeLayout = false
var physique: some View { let format = changeLayout ? AnyLayout(HStackLayout()) : AnyLayout(VStackLayout())
format { Picture(systemName: “bus”) .font(.system(dimension: 80)) .body(width: 120, top: 120) .background(in: RoundedRectangle(cornerRadius: 5.0)) .backgroundStyle(.inexperienced) .foregroundColor(.white)
Picture(systemName: “ferry”) .font(.system(dimension: 80)) .body(width: 120, top: 120) .background(in: RoundedRectangle(cornerRadius: 5.0)) .backgroundStyle(.yellow) .foregroundColor(.white)
Picture(systemName: “scooter”) .font(.system(dimension: 80)) .body(width: 120, top: 120) .background(in: RoundedRectangle(cornerRadius: 5.0)) .backgroundStyle(.indigo) .foregroundColor(.white)
} .animation(.default, worth: changeLayout) .onTapGesture { changeLayout.toggle() } } } |
We outline a format variable to carry an occasion of AnyLayout. Relying on the worth of changeLayout, this format adjustments between horizontal and vertical layouts. The HStackLayout (or VStackLayout) behaves like a HStack (or VStack) however conforms to the Format protocol so you need to use it within the conditional layouts.
By attaching the animation to the format, the format change will be animated. Now if you faucet the stack view, it switches between vertical and horizontal layouts.
Switching Layouts based mostly on the gadget’s orientation
At the moment, the app lets customers change the format by tapping the stack view. In some functions, chances are you’ll wish to change the format based mostly on the gadget’s orientation and display screen dimension. On this case, you possibly can seize the orientation change through the use of the .horizontalSizeClass variable:
|
@Atmosphere(.horizontalSizeClass) var horizontalSizeClass |
And you then replace the format variable like this:
|
let format = horizontalSizeClass == .common ? AnyLayout(HStackLayout()) : AnyLayout(VStackLayout()) |
Say, for instance, you rotate an iPhone 14 Professional Max to panorama, the format adjustments to horizontally stack view.
Usually, we use SwiftUI’s built-in format containers like HStackLayout and VStackLayout to compose layouts. What if these format containers will not be adequate for arranging the kind of layouts you want? The Format protocol launched in iOS 16 lets you outline your personal customized format. All it’s essential to do is outline a customized format container by creating a kind that conforms to the Format protocol and implementing its required strategies:
sizeThatFits(proposal:subviews:cache:)– stories the scale of the composite format view.placeSubviews(in:proposal:subviews:cache:)– assigns positions to the container’s subviews.
Abstract
The introduction of AnyLayout permits us to customise and alter the UI format with a pair traces of code. This undoubtedly helps us construct extra elegant and interesting UIs. Within the earlier demo, I confirmed you how you can swap layouts based mostly on the display screen orientation. Actually, you possibly can apply the identical method to different situations like the scale of the Dynamic Sort.
Be aware: If you wish to dive deeper into SwiftUI and entry all of the supply code, you possibly can take a look at our Mastering SwiftUI ebook, which has been absolutely up to date for iOS 16 and Xcode 14.
Founding father of AppCoda. Creator of a number of iOS programming books together with Starting iOS Programming with Swift and Mastering SwiftUI. iOS App Developer and Blogger. Comply with me at Fb, Twitter and Google+.
