Device.Timer wrapper for Xamarin with Prism DI support

DeviceTimer.cs

using System;
using System.Linq;
using System.Collections.Generic;
using Prism.Services;

namespace Xamarin.Forms
{
  public class DeviceTimer
  {
    readonly Action _Task;
    readonly TimeSpan _Interval;
    public bool IsRecurring { get; }
    readonly Action<TimeSpan, Func<bool>> _DeviceTimer;
    readonly List<TaskWrapper> _Tasks = new List<TaskWrapper>();
    public bool IsRunning => _Tasks.Any(t => t.IsRunning);

    public DeviceTimer(Action task, TimeSpan interval,
      bool isRecurring = false, bool start = false) : this(task, interval, isRecurring, start, Device.StartTimer)
    {
    }

    protected DeviceTimer(Action task, TimeSpan interval,
      bool isRecurring = false, bool start = false, Action<TimeSpan, Func<bool>> deviceTimer = null)
    {
      _DeviceTimer = deviceTimer ?? throw new ArgumentNullException(nameof(deviceTimer));
      _Task = task;
      _Interval = interval;
      IsRecurring = isRecurring;

      if (start)
        Start();
    }

    public void Restart()
    {
      Stop();
      Start();
    }

    public void Start()
    {
      if (IsRunning)
        // Already Running
        return;

      var wrapper = new TaskWrapper(_Task, IsRecurring, true);
      _Tasks.Add(wrapper);
      _DeviceTimer(_Interval, wrapper.RunTask);
    }

    public void Stop()
    {
      foreach (var task in _Tasks)
        task.IsRunning = false;
      _Tasks.Clear();
    }

    private class TaskWrapper
    {
      public bool IsRunning { get; set; }
      bool _IsRecurring;
      Action _Task;
      public TaskWrapper(Action task, bool isRecurring, bool isRunning)
      {
        _Task = task;
        _IsRecurring = isRecurring;
        IsRunning = isRunning;
      }

      public bool RunTask()
      {
        if (IsRunning)
        {
          _Task();
          if (_IsRecurring)
            return true;
        }

        return IsRunning = false;
      }
    }
  }
}

namespace Prism.Services
{
  public class PrismDeviceTimer : Xamarin.Forms.DeviceTimer
  {
    public PrismDeviceTimer(IDeviceService deviceService, Action task, TimeSpan interval,
      bool isRecurring = false, bool start = false) : base(task, interval, isRecurring, start, GetMethod(deviceService))
    {
    }

    static Action<TimeSpan, Func<bool>> GetMethod(IDeviceService deviceService)
    {
      if (deviceService == null) throw new ArgumentNullException(nameof(deviceService));
      return deviceService.StartTimer;
    }

  }
}

IDeviceService can easily be removed an replaced by the Xamarin static one for projects without Prism.