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UIView.SpeakScreenStatusDidChangeNotification 属性

定义

SpeakScreenStatusDidChange 的通知常量

[Foundation.Advice("Use UIView.Notifications.ObserveSpeakScreenStatusDidChange helper method instead.")]
[Foundation.Field("UIAccessibilitySpeakScreenStatusDidChangeNotification", "UIKit")]
[ObjCRuntime.Introduced(ObjCRuntime.PlatformName.iOS, 8, 0, ObjCRuntime.PlatformArchitecture.All, null)]
[ObjCRuntime.Unavailable(ObjCRuntime.PlatformName.WatchOS, ObjCRuntime.PlatformArchitecture.All, null)]
public static Foundation.NSString SpeakScreenStatusDidChangeNotification { [ObjCRuntime.Introduced(ObjCRuntime.PlatformName.iOS, 8, 0, ObjCRuntime.PlatformArchitecture.All, null)] [ObjCRuntime.Unavailable(ObjCRuntime.PlatformName.WatchOS, ObjCRuntime.PlatformArchitecture.All, null)] get; }
member this.SpeakScreenStatusDidChangeNotification : Foundation.NSString

属性值

NSString 常量 应用作 NSNotificationCenter 的标记。

属性

注解

此常量可用于注册 NSNotificationCenter 此通知的侦听器。 这是 NSString 而不是字符串,因为这些值可以用作某些本机库中的标记,而不是纯粹用于其实际字符串内容。 回调的“notification”参数包含特定于通知类型的额外信息。

// Lambda style
NSNotificationCenter.DefaultCenter.AddObserver (
        UIView.SpeakScreenStatusDidChangeNotification, (notification) => {Console.WriteLine ("Received the notification UIView", notification); }


// Method style
void Callback (NSNotification notification)
{
    Console.WriteLine ("Received a notification UIView", notification);
}

void Setup ()
{
    NSNotificationCenter.DefaultCenter.AddObserver (UIView.SpeakScreenStatusDidChangeNotification, Callback);
}

适用于