Question

我想向Xamarin.Forms应用程序添加后台服务，以每隔X分钟从服务器获取一些数据..因此，我添加了BroadcastReceiver，服务和警报管理器来完成这项工作，并且该服务成功启动单击按钮，但是当我尝试停止该服务时，它不会停止！

此类可打开/关闭服务。

[assembly: Dependency(typeof(Notifications))]
namespace FleetDesigner.Droid
{
class Notifications : Activity, IAndroidNotifications
{
    Context context = Android.App.Application.Context;

    public void StartNotificationsService()
    {
        //Start Notifications Service
        Intent myIntent = new Intent(context, typeof(NotificationsService));
        context.StartService(myIntent);

        //Show Snackbar message
        Activity activity = CrossCurrentActivity.Current.Activity;
        Android.Views.View activityRootView = activity.FindViewById(Android.Resource.Id.Content);
        Snackbar.Make(activityRootView, "Notifications activées", Snackbar.LengthLong).Show();
    }

    public void StopNotificationsService()
    {
        //Stop Notifications Service
        Intent myIntent = new Intent(context, typeof(NotificationsService));
        context.StopService(myIntent);

        //Show Snackbar message
        Activity activity = CrossCurrentActivity.Current.Activity;
        Android.Views.View activityRootView = activity.FindViewById(Android.Resource.Id.Content);
        Snackbar.Make(activityRootView, "Notifications désactivées", Snackbar.LengthLong).Show();
    }

}
}

这是服务类别

namespace FleetDesigner.Droid
{
[Service
    (Name = "com.fleet.app.NotificationsService",
     Process = "com.fleet.app.NotificationsService",
     Label = "Service Notifications"
    )]

class NotificationsService : Service
{
    AlarmManager manager;
    Intent myIntent;
    PendingIntent pendingIntent;

    public override IBinder OnBind(Intent intent)
    {
        return null;
    }

    //[return: GeneratedEnum]
    public override StartCommandResult OnStartCommand(Intent intent, StartCommandFlags flags, int startId)
    {
        //return base.OnStartCommand(intent, flags, startId);
        manager = (AlarmManager)GetSystemService(Context.AlarmService);

        myIntent = new Intent(this, typeof(NotificationsAlarm));
        pendingIntent = PendingIntent.GetBroadcast(this, 0, myIntent, 0);

        manager.SetRepeating(AlarmType.RtcWakeup, SystemClock.ElapsedRealtime() + 1000, 60 * 1000, pendingIntent);


        return StartCommandResult.NotSticky;
    }

    public override void OnDestroy()
    {
        base.OnDestroy();
        pendingIntent.Cancel();
        manager.Cancel(pendingIntent);
    }

}
}

最后，这是广播接收器（该服务的逻辑只是显示本地通知）

namespace FleetDesigner.Droid
{
[BroadcastReceiver(Enabled = true)]
public class NotificationsAlarm : BroadcastReceiver
{
    static Random random = new Random();
    public override void OnReceive(Context context, Intent intent)
    {
        //showNotifications(context, intent);
        int m = random.Next(9999 - 1000) + 1000;
        var title = "Title";
        var channelName = "TestChannel";
        string channelID = "TestChannel";
        string OverSpeedChannelName = "OverSpeedChannel";

        string notificationChannel = channelName;

        using (var notificationManager = NotificationManager.FromContext(context))
        {
            if (Build.VERSION.SdkInt >= BuildVersionCodes.O)
            {
                NotificationChannel channel = null;
                if (channel == null)
                {
                    channel = new NotificationChannel(channelName, channelName, NotificationImportance.Default)
                    {
                        LockscreenVisibility = NotificationVisibility.Public
                    };
                    channel.SetShowBadge(true);
                    notificationManager.CreateNotificationChannel(channel);
                }
                channel.Dispose();

                NotificationChannel overspeedchannel = null;
                if (overspeedchannel == null)
                {
                    overspeedchannel = new NotificationChannel(OverSpeedChannelName, OverSpeedChannelName, NotificationImportance.Default)
                    {
                        LockscreenVisibility = NotificationVisibility.Secret
                    };
                    overspeedchannel.SetShowBadge(true);
                    notificationManager.CreateNotificationChannel(overspeedchannel);
                }
                overspeedchannel.Dispose();
            }

            var notificationBuilder = new NotificationCompat.Builder(context, channelID)
                   .SetContentTitle("Title "+m)
                   .SetContentText("Notification Content")
                   .SetSmallIcon(Resource.Drawable.ic_action_map)
                   .SetShowWhen(false)
                   .SetChannelId(notificationChannel);

            var notification = notificationBuilder.Build();
            notificationManager.Notify(m, notification);
        }
    }
}

所以，正如我所说的，此代码中的唯一问题是..即使我调用stopService（），通知（后台服务）也不会停止！

有什么建议吗？谢谢

Android服务会停止吗？

0 个答案: