c# - ObservableDictionary binding to combobox display value(MVVM) -

i have problem databinding. have wpf (mvvm) user control project. there comboboxes , labels. every combobox binds observabledictionary<int,string>. problem need show string part of dictionary on combobox.

also, combobox itemsource changes depends on selected @ previous combobox. , mvvm pattern. there model , view model.

i tried setting displaypathetc. couldn't show strings on combos. seeing [0, sample], [1,yes].

<combobox horizontalalignment="left" margin="250,15,0,0" verticalalignment="top" width="120" name="cbxerisim" selectionchanged="cbxerisim_selectionchanged" itemssource="{binding derisimkodu}" /> <combobox horizontalalignment="left" margin="250,45,0,0" verticalalignment="top" width="120" name="cbxteklifdurum" selectionchanged="cbxteklifdurum_selectionchanged" itemssource="{binding dteklifdurumu}"/> <combobox horizontalalignment="left" margin="250,75,0,0" verticalalignment="top" width="120" name="cbxteklifsonuc" selectionchanged="cbxteklifsonuc_selectionchanged" itemssource="{binding dteklifsonuc}"/> 

you need set following properties (i'm assuming observabledictionary inherits idictionary<tkey, tvalue>):

selectedvaluepath="key" displaymemberpath="value" 

i have tested using this implementation of observabledictionary<tkey, tvalue>

in view:

<combobox width="35" selectedvaluepath="key" displaymemberpath="value" itemssource ="{binding firstdictionary}"/> 

and view model:

public class viewmodel {     private observabledictionary<int, string> _firstdictionary;      public viewmodel()     {         _firstdictionary = new observabledictionary<int, string>()                 {                     new keyvaluepair<int, string>(1, "a"),                     new keyvaluepair<int, string>(2, "b"),                     new keyvaluepair<int, string>(3, "c")                 };     }      public observabledictionary<int, string> firstdictionary     {         { return _firstdictionary; }         set { _firstdictionary = value; }     } }