public class DeviceFamiliyTrigger : StateTriggerBase
{
  private string _deviceFamily;
  public string DeviceFamily
  {
    get { return _deviceFamily; }
    set
    {
      var qualifiers = Windows.ApplicationModel.Resources.Core.ResourceContext.GetForCurrentView().QualifiersValues;
      if(qualifiers.ContainsKey("DeviceFamily"))
        SetActive(qualifiers["DeviceFamily"] == (_deviceFDamily = value));
      else
        SetActive(false);
    }
  }
}