public SpeakerByIdModelProvider(Speaker s)
 {
     this.s = s;
     this.Speakers = new ObservableCollection<Speaker>();
 }
 public SpeakerByIdModelProvider SpeakerByIdModelProvider(Speaker s)
 {
     SpeakerByIdModelProvider provider = null;
     if (!_speakerByIdModelProvider.ContainsKey(s))
     {
         provider = new SpeakerByIdModelProvider(s);
         provider.LoadData();
         _speakerByIdModelProvider.Add(s, provider);
     }
     else
     {
         provider = _speakerByIdModelProvider[s];
     }
     return provider;
 }