SwiftUI Academy · 课时

将视图绑定到 ViewModel

使用视图模型属性驱动视图。

将视图绑定到 ViewModel 是 CoddyKit 上的免费 SwiftUI Academy 课时。这是第 3 节课，共 4 节。你可以在下方免费阅读本课时的完整内容 — 然后在浏览器中使用内置代码编辑器和全天候 AI 导师进行实践。这是 SwiftUI Academy 学习路径的一部分，你的进度在网页和 CoddyKit 应用中同步。 SwiftUI Academy 课程共包含 4 节课。

本课时的部分内容尚未翻译，以英文显示。

Owning the ViewModel

The view that creates a ViewModel owns it. Use @State to hold the instance so it survives across re-renders of the view.

@State private var vm = ProfileViewModel()

Reading State in body

Inside body, read the ViewModel properties like normal values. SwiftUI re-runs body whenever those observed properties change.

Text(vm.greeting)

Calling Actions on Tap

Wire a button action straight to a ViewModel method. The view stays simple, just forwarding the intent to the brain.

Button("Reload") {
    vm.load()
}

Driving Conditional UI

Let ViewModel state choose the layout. Switch on isLoading to show a spinner or the content with no extra view logic.

if vm.isLoading {
    ProgressView()
} else {
    Text(vm.greeting)
}

Two-Way Fields

For text input, bind a TextField to a ViewModel property with the dollar sign. Edits flow back into the ViewModel instantly.

TextField("Name", text: $vm.name)

Loading When the View Appears

Use the .task modifier to call the ViewModel as the view shows up, kicking off the first data load automatically.

.task {
    await vm.load()
}

Lists From the ViewModel

Feed a List from a ViewModel array. When the model updates its items, SwiftUI diffs the rows and animates the change for you.

List(vm.items) { item in
    Text(item.title)
}

Keep the View Declarative

A well-bound view reads like a sentence: show this state, run that action. No calculations sneak into the body.

Passing the ViewModel Down

Child views can take a ViewModel as a plain property. The parent owns it; children just read and call its methods.

DetailView(vm: vm)

Previews Love ViewModels

In a preview, hand the view a ViewModel filled with sample data. You can showcase loading, empty, and full states side by side. 👀

A Bound Screen at a Glance

This view owns a ViewModel, shows its greeting, and reloads on tap, a complete binding in just a few lines of SwiftUI.

Text(vm.greeting)
Button("Reload") { vm.load() }

Quick Check

How should a view own a fresh ViewModel instance?

Recap: Binding Views to ViewModels

You connected a view to its ViewModel with @State, read its properties in body, and routed taps and input back to it. Next: dependency injection.

常见问题解答

「将视图绑定到 ViewModel」课时是免费的吗？

是的 — 「将视图绑定到 ViewModel」的完整文本可在网页上免费阅读。要进行交互式练习（内置代码编辑器和全天候 AI 导师）并解锁 SwiftUI Academy 课程的其余内容，请升级到 CoddyKit PRO。 SwiftUI Academy 课程共包含 4 节课。

「将视图绑定到 ViewModel」这节课中我会学到什么？

使用视图模型属性驱动视图。你通过在浏览器中直接运行的动手代码来练习 SwiftUI Academy，全天候 AI 导师会在你学习这节课的过程中回答你的问题。

学习 SwiftUI Academy 需要有经验吗？

无需任何先前经验。CoddyKit 上的 SwiftUI Academy 课程适合初学者到高级学习者，你可以从这里开始或从头开始，按照自己的节奏学习。这是第 3 节课，共 4 节。

「将视图绑定到 ViewModel」课时需要多长时间？

大多数 CoddyKit 课程大约需要 5–10 分钟。每节课都很精短且互动，所以你能稳步进步，并在网页和应用中从离开的地方继续。

我能在这节 SwiftUI Academy 课中编写并运行代码吗？

能。每节 SwiftUI Academy 课都包含内置代码编辑器，你可以在浏览器中直接编写并运行真实代码，并获得即时 AI 反馈 — 无需本地设置。

此课程中的所有课时

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