![]() Speaking of lazy stuff, we can now use LazyVGrid and LazyHGrid to build something similar to UICollection view, but we’ll leave that to another time. The same concept is valid for HStack and its lazy counterpart. SwiftUI Basics: Dynamic Lists, HStack VStack, Images and How to do Navigation in your Swift UI app (2019) // Learn to use SwiftUI Basics Dynamic Lists in this swift ui tutorial for. It is similar to List, you see views being created as you scroll down the list. Try looking at the console with the parameter lazy set to true. We could use List, but what if we want a ScrollView with a ForEach similar to the example above? Well now we can use LazyVStack and LazyHStack! Try the same with List, you’ll see stuff printed as you scroll. My example has 100 posts, you’ll see 100 prints, so all the views are created once you load the container. Print("onAppear post = \(post.id) \(erId)")Īnd see how many times onAppear post = … is printed on the console. If you want to check what’s going on, try putting a print in onAppear It works, but it loads all the PostView at once. ![]() ![]() This is an example with List, as I said it provides lazy loading and that’s one way to go.īut what if you want to use a ScrollView with VStack instead? My example is pretty simple, I have a JSON with a list of posts and want to show them on screen as a scrollable list. I’ll show you what’s new in a minute, as usual the code is on GitHub. Refresh the page, check Medium ’s site status, or find something interesting to read. WWDC 2020 brought us a nice addition: lazy stacks. SwiftUI Tutorial: Working With Stacks VStack, HStack, and ZStack by Arc Sosangyo Better Programming Write Sign up 500 Apologies, but something went wrong on our end. One alternative was using the List component, which implements lazy loading, and I wrote something about infinite scrolling you may want to check out. Those components load all their children up front, so they’re not suitable for implementing a long list of items, as you’d rather have lazy loading. I think having a VStack containing all the elements in a List or ScrollView breaks the UI performance. ![]() When some of its content is scrolled off-screen in a ScrollView. It does not appear to do any optimization for the presentation of items that are off-screen. Then, show the title by initializing Text() with an argument landmark.title which will become a row view of the List.SwiftUI introduced from the very beginning the components HStack and VStack to group views in an horizontal or vertical stack. A VStack is a free-form StackView that contains arbitrary combinations of other views and manages their layout and organization. Then, create a closure with the parameter called landmark, which will have a landmark object on each iteration. Next, create a list view inside the body property with the List initializer and pass landmarks to it as a parameter. Switch back to the LandmarkList.swift file and assign the landmarksData to the landmarks property. Landmark(title: "Mont St Michel", country: "France") Landmark(title: "Neuschwanstein", country: "Germany"), Landmark(title: "Alpine", country: "Austria"), Landmark(title: "Steinweg", country: "Germany"), Landmark(title: "Isle Of Skye", country: "Switzerland"),
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