c# - Binding issue MVVM -

I have a listbox that has a population through a view model and a datatamate in which I also have the binding. The problem is binding in the DataTemplate is not working here. My code is:

ViewModel:

  Private Zero Notified Installed (String Properties Name) {PropertyChangedEventHandler Handler = property changed; If (empty! = Handler) {handler (this, new property change event event (property name)); }} #thandriven personal strings strHeaderText; Public String HeaderText {get (if! = This.Trips) {if (null! = This._trips.name) {return._trips.name; }} Return trip ";} Set {this.strHeaderText = value;}} Public TripTypeViewModel () {this.TripTypeViewModelDataSource.Clear () TripTipsTespeTypeViewModelDataSource.FirstOrDefault () trip in tripps} {This. TripTypeViewModelDataSource.Add (tt) ;}} ... private observable collection & amp; lieutenant; TripType & gt; tripTypeViewModelDataSource; Public Supervisory Collection & amp; TripType & gt; TripTypeViewModelDataSource {Get (if (tap == this.tripTypeViewModelDataSource) {this.tripTypeViewModelDataSource = New Observation Collection & lt; TripType & gt; ();} This. TripTypeViewModelDataSource;}}  

See this my

 < Code>  name = "ITLB" itemsource = "{binding trip typeplamodel.tripTypeViewModelDataSource}"> > LT; DataTemplate & gt; & lt; button content = "{binding trip TypeModel.HeaderText} "width =" auto "height =" auto "/>