Structure

SceneStorage

A property wrapper type that reads and writes to persisted, per-scene storage. あるプロパティラッパー型、それは永続化された、シーンごとのストレージを読み書きします。

Declaration 宣言 

@frozen @propertyWrapper struct SceneStorage<Value>

Overview 概要

You use SceneStorage when you need automatic state restoration of the value. SceneStorage works very similar to State, except its initial value is restored by the system if it was previously saved, and the value is· shared with other SceneStorage variables in the same scene.

The system manages the saving and restoring of SceneStorage on your behalf. The underlying data that backs SceneStorage is not available to you, so you must access it via the SceneStorage property wrapper. The system makes no guarantees as to when and how often the data will be persisted.

Each Scene has its own notion of SceneStorage, so data is not shared between scenes.

Ensure that the data you use with SceneStorage is lightweight. Data of a large size, such as model data, should not be stored in SceneStorage, as poor performance may result.

If the Scene is explicitly destroyed (e.g. the switcher snapshot is destroyed on iPadOS or the window is closed on macOS), the data is also destroyed. Do not use SceneStorage with sensitive data.

Topics 話題

Storing a Value

init(wrappedValue: Value, String)
Creates a property that can save and restore a URL.
init(wrappedValue: Value, String)
Creates a property that can save and restore an integer.
init(wrappedValue: Value, String)
Creates a property that can save and restore a double.
init(wrappedValue: Value, String)
Creates a property that can save and restore a string.
init(wrappedValue: Value, String)
Creates a property that can save and restore a boolean.
init(wrappedValue: Value, String)
Creates a property that can save and restore a string, transforming it to a RawRepresentable data type.
init(wrappedValue: Value, String)
Creates a property that can save and restore data.
init(wrappedValue: Value, String)
Creates a property that can save and restore an integer, transforming it to a RawRepresentable data type.

Storing an Optional Value

init(String)
Creates a property that can save and restore an Optional string.
Available when Value conforms to ExpressibleByNilLiteral. ValueがExpressibleByNilLiteralに準拠する場合に利用可能です。
init<R>(String)
Creates a property that can save and restore an Optional integer, transforming it to an Optional RawRepresentable data type.
init(String)
Creates a property that can save and restore an Optional double.
Available when Value conforms to ExpressibleByNilLiteral. ValueがExpressibleByNilLiteralに準拠する場合に利用可能です。
init(String)
Creates a property that can save and restore an Optional boolean.
Available when Value conforms to ExpressibleByNilLiteral. ValueがExpressibleByNilLiteralに準拠する場合に利用可能です。
init(String)
Creates a property that can save and restore an Optional data.
Available when Value conforms to ExpressibleByNilLiteral. ValueがExpressibleByNilLiteralに準拠する場合に利用可能です。
init(String)
Creates a property that can save and restore an Optional URL.
Available when Value conforms to ExpressibleByNilLiteral. ValueがExpressibleByNilLiteralに準拠する場合に利用可能です。
init(String)
Creates a property that can save and restore an Optional integer.
Available when Value conforms to ExpressibleByNilLiteral. ValueがExpressibleByNilLiteralに準拠する場合に利用可能です。
init<R>(String)
Creates a property that can save and restore an Optional string, transforming it to an Optional RawRepresentable data type.

Getting the Value 値を取得する

var wrappedValue: Value
The underlying value referenced by the state variable. 状態変数によって参照される基礎をなす値。
var projectedValue: Binding<Value>
A binding to the state value. 状態値へのバインディング。

Default Implementations 省略時実装

DynamicProperty Implementations

Relationships 関係

Conforms To 次に準拠

See Also 参照

App State

struct AppStorage
A property wrapper type that reflects a value from UserDefaults and invalidates a view on a change in value in that user default. あるプロパティラッパー型、それはUserDefaultsからのある値を反映します、そしてそのユーザデフォルトの中の値における変更に関してあるビューを無効にします。