Notification.BigTextStyle没有出现

Question

所以我正在学习在xamarin android中使用BigTextStyle进行通知。出于某种原因，每当我运行我的代码时，bigText和SetSummaryText都不会出现在通知中。谁知道为什么？我的代码如下：

     protected override void OnCreate(Bundle bundle)
    {
        base.OnCreate(bundle);

        // Set our view from the "main" layout resource
         SetContentView (Resource.Layout.Main);
        Notification.Builder builder = new Notification.Builder(this)
            .SetContentTitle("Big Text")
            .SetSmallIcon(Resource.Drawable.Icon);


        Notification.BigTextStyle textStyle = new Notification.BigTextStyle();

        string longTextMessage = "I went up on one pair of stairs.";
        longTextMessage += " / Just like me. ";

        textStyle.BigText(longTextMessage);
        textStyle.SetSummaryText("The summary text goes here. ");
        builder.SetStyle(textStyle);
        Notification notification = builder.Build();


        NotificationManager notificationManager =
            GetSystemService(Context.NotificationService) as NotificationManager;

        const int notificationId = 0;
        notificationManager.Notify(notificationId, notification);
    }

Answer 1

var notification = new Notification.Builder(Application.Context)
    .SetSmallIcon(Resource.Mipmap.Icon)
    .SetLargeIcon(BitmapFactory.DecodeResource(Application.Context.Resources, Resource.Mipmap.Icon))
    .SetAutoCancel(true)
    .SetStyle(new Notification
              .BigTextStyle()
              .SetSummaryText("Summary Text")
              .SetBigContentTitle("Content Title")
              .BigText("Big Text Area")
             )
    .Build();
var notificationManager = (NotificationManager)Application.Context.GetSystemService(Context.NotificationService);
notificationManager.Notify(1, notification);