SwiftUI Academy · レッスン

プログラムによるナビゲーションパス

navigationDestination のパスでナビゲーションを制御します。

「プログラムによるナビゲーションパス」はCoddyKit上の無料SwiftUI Academyレッスンです。これはレッスン4/4です。下記で完全なレッスンを無料で読むことができます。その後、ブラウザ内の組み込みコードエディタと24時間対応のAIチューターでハンズオン演習できます。これはSwiftUI Academy学習パスの一部であり、ウェブとCoddyKitアプリ全体で進捗が同期されます。 SwiftUI Academyコースには全4レッスンが含まれています。

このレッスンの一部はまだ翻訳されておらず、英語で表示されています。

Navigating From Code

Sometimes a tap is not enough. After saving a form you may want to jump screens yourself. SwiftUI lets you drive the stack from code. ⚙️

A Path You Control

Give NavigationStack a path binding. This array is the live list of screens currently pushed, and editing it changes navigation instantly.

@State private var path = NavigationPath()
NavigationStack(path: $path) { HomeView() }

Push by Appending

Append a value to the path and SwiftUI pushes the matching screen. No tap needed, just change the array.

path.append(book)

Routing the Value

A navigationDestination maps each value type in the path to a view, so appended data knows which screen to become.

.navigationDestination(for: Book.self) { book in
    DetailView(book: book)
}

Pop With Remove

Removing the last element pops a screen, exactly like the back button. You stay in full control of the stack from code.

path.removeLast()

Jump Home Instantly

To return all the way to the root, empty the path. Every pushed screen disappears at once, perfect for a Done button. 🏠

path.removeLast(path.count)

Deep Linking

Because the path is just data, you can build it from a URL or notification, pushing several screens so users land deep inside the app.

NavigationPath Holds Mixed Types

A NavigationPath can store values of different types together, letting one stack route books, users, and settings without a shared enum.

Or Use a Typed Array

If every screen shares one type, a plain typed array works as the path and reads a little more clearly than NavigationPath.

@State private var path: [Book] = []

State Drives the Stack

Navigation becomes state. The visible screens always mirror the path array, so your UI stays predictable and easy to reason about.

Test and Restore

Since the path is plain data, you can save it and restore it, recreating exactly where the user left off when they reopen the app.

Quick Check

What happens when you append a value to a NavigationStack path?

Recap: Programmatic Paths

You bind a path to NavigationStack and push or pop screens by editing that array, turning navigation into predictable, testable state. 🎉

よくある質問