SwiftUI Academy · 课时

添加新项目

追加行，并让列表保持同步。

添加新项目 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。

Growing the List

A useful list does not stay frozen. Letting users add items is the other half of editing, and it keeps your @State array in charge. ✨

Append to Your Array

Adding a row is just adding data. Call append on your @State array and SwiftUI inserts a fresh row automatically.

items.append(Item(name: "Bread"))

A Toolbar Add Button

Most apps add items from a plus button. Put a Button in the toolbar that calls your add logic when tapped.

.toolbar {
    Button("Add") { addItem() }
}

Use a System Plus Icon

Swap the text for an SF Symbol so it reads as Add. The plus symbol is the universal cue users already understand.

Button {
    addItem()
} label: {
    Image(systemName: "plus")
}

Writing addItem

Your addItem function creates a new model value and appends it. Keep it small and let the array drive the UI.

func addItem() {
    items.append(Item(name: "New"))
}

Add From a TextField

Often the new item comes from typing. Bind a TextField to a draft string, then append that text when the user confirms.

@State private var draft = ""
TextField("Item", text: $draft)

Append Then Clear

After appending, reset the draft so the field is empty for the next entry. Clearing draft keeps the form feeling fresh.

items.append(Item(name: draft))
draft = ""

Guard Against Blanks

Do not add empty rows. A quick guard on the trimmed draft stops accidental blank items from cluttering your list.

guard !draft.trimmingCharacters(
    in: .whitespaces).isEmpty
else { return }

New Rows Animate In

Because the array changed, SwiftUI slides the new row into place. Wrap the append in withAnimation for an even snappier feel.

withAnimation {
    items.append(Item(name: draft))
}

Insert at the Top

Want newest first? Use insert(at:) with index 0 instead of append, and the row appears at the top of the list.

items.insert(Item(name: draft),
             at: 0)

One Source of Truth

Add, delete, and move all mutate the same @State array. That single source of truth keeps your whole list consistent.

Quick Check

How do you add a new row to a SwiftUI list?

Recap: Adding Items

You can grow a list by appending to its @State array, often from a toolbar button or a TextField, with guards and animation. 🎉

常见问题解答

「添加新项目」课时是免费的吗？

是的 — 「添加新项目」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。

「添加新项目」这节课中我会学到什么？

追加行，并让列表保持同步。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。

「添加新项目」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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