UIView.VoiceOverStatusDidChangeNotification 属性

定义

命名空间:

UIKit

程序集:

Xamarin.iOS.dll

VoiceOverStatusDidChange 的通知常量

[Foundation.Advice("Use UIView.Notifications.ObserveVoiceOverStatusDidChange helper method instead.")]
[Foundation.Field("UIAccessibilityVoiceOverStatusDidChangeNotification", "UIKit")]
[ObjCRuntime.Introduced(ObjCRuntime.PlatformName.TvOS, 11, 0, ObjCRuntime.PlatformArchitecture.All, null)]
[ObjCRuntime.Introduced(ObjCRuntime.PlatformName.iOS, 11, 0, ObjCRuntime.PlatformArchitecture.All, null)]
[ObjCRuntime.Unavailable(ObjCRuntime.PlatformName.WatchOS, ObjCRuntime.PlatformArchitecture.All, null)]
public static Foundation.NSString VoiceOverStatusDidChangeNotification { [ObjCRuntime.Introduced(ObjCRuntime.PlatformName.TvOS, 11, 0, ObjCRuntime.PlatformArchitecture.All, null)] [ObjCRuntime.Introduced(ObjCRuntime.PlatformName.iOS, 11, 0, ObjCRuntime.PlatformArchitecture.All, null)] [ObjCRuntime.Unavailable(ObjCRuntime.PlatformName.WatchOS, ObjCRuntime.PlatformArchitecture.All, null)] get; }

member this.VoiceOverStatusDidChangeNotification : Foundation.NSString

属性值

NSString

NSString 常量 应用作 NSNotificationCenter 的标记。

属性

AdviceAttribute FieldAttribute IntroducedAttribute UnavailableAttribute

注解

此常量可用于 NSNotificationCenter 注册此通知的侦听器，开发人员也可以改用强类型通知 ObserveVoiceOverStatusDidChange 。 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.VoiceOverStatusDidChangeNotification, (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.VoiceOverStatusDidChangeNotification, Callback);
}