Structure

ForEach

A structure that computes views on demand from an underlying collection of identified data.

Declaration 宣言 

struct ForEach<Data, ID, Content> where Data : RandomAccessCollection, ID : Hashable

Overview 概要

Use ForEach to provide views based on a RandomAccessCollection of some data type. Either the collection’s elements must conform to Identifiable or you need to provide an id parameter to the ForEach initializer.

The following example creates a NamedFont type that conforms to Identifiable, and an array of this type called namedFonts. A ForEach instance iterates over the array, producing new Text instances that display examples of each SwiftUI Font style provided in the array.


private struct NamedFont: Identifiable {
    let name: String
    let font: Font
    var id: String { name }
}


private let namedFonts: [NamedFont] = [
    NamedFont(name: "Large Title", font: .largeTitle),
    NamedFont(name: "Title", font: .title),
    NamedFont(name: "Headline", font: .headline),
    NamedFont(name: "Body", font: .body),
    NamedFont(name: "Caption", font: .caption)
]


var body: some View {
    ForEach(namedFonts) { namedFont in
        Text(namedFont.name)
            .font(namedFont.font)
    }
}

A vertically arranged stack of labels showing various standard fonts,

Topics 話題

Creating a Collection from a Range

init(Range<Int>, content: (Int) -> Content)
Creates an instance that computes views on demand over a given constant range. あるインスタンスを作成します、それは、ビューそれらを必要に応じてある与えられた定数範囲にわたって計算するものです。
Available when Data is Range<Int>, ID is Int, and Content conforms to View. DataがRange<Int>である、IDがIntである、そしてContentがViewに準拠する場合に利用可能です。

Creating a Collection from Data

init(Data, content: (Data.Element) -> Content)
Creates an instance that uniquely identifies and creates views across updates based on the identity of the underlying data. あるインスタンスを作成します、それは、ビューそれらを更新を越えてその基礎をなすデータの同一性に基づいて特有に識別および作成するものです。
Available when Data conforms to RandomAccessCollection, ID is Data.Element.ID, Content conforms to View, and Data.Element conforms to Identifiable. DataがRandomAccessCollectionに準拠する、IDがData.Element.IDである、ContentがViewに準拠する、そしてData.ElementがIdentifiableに準拠する場合に利用可能です。
init<C>(Binding<C>, content: (Binding<C.Element>) -> Content)
Creates an instance that uniquely identifies and creates views across updates based on the identity of the underlying data. あるインスタンスを作成します、それは、ビューそれらを更新を越えてその基礎をなすデータの同一性に基づいて特有に識別および作成するものです。
Available when Data conforms to RandomAccessCollection, ID conforms to Hashable, and Content conforms to View. DataがRandomAccessCollectionに準拠する、IDがHashableに準拠する、そしてContentがViewに準拠する時に利用可能です。
init(Data, id: KeyPath<Data.Element, ID>, content: (Data.Element) -> Content)
Creates an instance that uniquely identifies and creates views across updates based on the provided key path to the underlying data’s identifier. あるインスタンスを作成します、それは、ビューそれらを更新を越えてその基礎をなすデータのもつ識別子へのこの提供されたキーパスに基づいて特有に識別および作成するものです。
Available when Data conforms to RandomAccessCollection, ID conforms to Hashable, and Content conforms to View. DataがRandomAccessCollectionに準拠する、IDがHashableに準拠する、そしてContentがViewに準拠する時に利用可能です。
init<C>(Binding<C>, id: KeyPath<C.Element, ID>, content: (Binding<C.Element>) -> Content)
Creates an instance that uniquely identifies and creates views across updates based on the identity of the underlying data. あるインスタンスを作成します、それは、ビューそれらを更新を越えてその基礎をなすデータの同一性に基づいて特有に識別および作成するものです。
Available when Data conforms to RandomAccessCollection, ID conforms to Hashable, and Content conforms to View. DataがRandomAccessCollectionに準拠する、IDがHashableに準拠する、そしてContentがViewに準拠する時に利用可能です。

Generating Rotor Content

init(Data, content: (Data.Element) -> Content)
Creates an instance that generates Rotor content by combining, in order, individual Rotor content for each element in the data given to this ForEach.
Available when Data conforms to RandomAccessCollection, ID is Data.Element.ID, Content conforms to AccessibilityRotorContent, and Data.Element conforms to Identifiable.
init(Data, id: KeyPath<Data.Element, ID>, content: (Data.Element) -> Content)
Creates an instance that generates Rotor content by combining, in order, individual Rotor content for each element in the data given to this ForEach.
Available when Data conforms to RandomAccessCollection, ID conforms to Hashable, and Content conforms to AccessibilityRotorContent.

Creating a Collection of Table Rows

init<V>(Range<Int>, content: (Int) -> Content)
Creates an instance that computes table rows on demand over a given constant range.
Available when Data conforms to RandomAccessCollection, ID conforms to Hashable, and Content conforms to TableRowContent.
init(Data, content: (Data.Element) -> Content)
Creates an instance that uniquely identifies and creates table rows across updates based on the identity of the underlying data.
Available when Data conforms to RandomAccessCollection, ID conforms to Hashable, and Content conforms to TableRowContent.
init<V>(Data, id: KeyPath<Data.Element, ID>, content: (Data.Element) -> Content)
Creates an instance that uniquely identifies and creates table rows across updates based on the provided key path to the underlying data’s identifier.
Available when Data conforms to RandomAccessCollection, ID conforms to Hashable, and Content conforms to TableRowContent.

Accessing Content 内容にアクセスする

var content: (Data.Element) -> Content
A function to create content on demand using the underlying data.
var data: Data
The collection of underlying identified data that SwiftUI uses to create views dynamically. 基礎をなす識別されたデータのコレクション、それはSwiftUIが使用してビューを動的に作成するものです。

Default Implementations 省略時実装

DynamicViewContent Implementations
TableRowContent Implementations
AccessibilityRotorContent Implementations
DynamicTableRowContent Implementations
View Implementations

Relationships 関係

Conforms To 次に準拠

  • AccessibilityRotorContent
    Conforms when Data conforms to RandomAccessCollection, ID conforms to Hashable, and Content conforms to AccessibilityRotorContent.
  • DynamicTableRowContent
    Conforms when Data conforms to RandomAccessCollection, ID conforms to Hashable, and Content conforms to TableRowContent.
  • DynamicViewContent
    Conforms when Data conforms to RandomAccessCollection, ID conforms to Hashable, and Content conforms to View. DataがRandomAccessCollectionに準拠する、IDがHashableに準拠する、そしてContentがViewに準拠する時に準拠します。
  • TableRowContent
    Conforms when Data conforms to RandomAccessCollection, ID conforms to Hashable, and Content conforms to TableRowContent.
  • View
    Conforms when Data conforms to RandomAccessCollection, ID conforms to Hashable, and Content conforms to View. DataがRandomAccessCollectionに準拠する、IDがHashableに準拠する、そしてContentがViewに準拠する時に準拠します。

See Also 参照

Lists

Displaying Data in Lists
Visualize collections of data with platform-appropriate appearance.
struct List
A container that presents rows of data arranged in a single column, optionally providing the ability to select one or more members.
struct ListItemTint
The configuration of a tint effect applied to content within a List.
struct Section
A container view that you can use to add hierarchy to certain collection views.
protocol DynamicViewContent
A type of view that generates views from an underlying collection of data. ビューのひとつの型、それはある基礎をなすデータのコレクションからビューそれらを生成するものです。
Available when Data conforms to RandomAccessCollection, ID conforms to Hashable, and Content conforms to View. DataがRandomAccessCollectionに準拠する、IDがHashableに準拠する、そしてContentがViewに準拠する時に利用可能です。