I am sorry for the delayed reply!
Have you also inherited the TabItems?
You need to inherit them as well and set their DefaultStyleKey accordingly.
Also please make sure that you override these two methods in the RadTabControl:
1. IsItemItsOwnContainer - in your case it should be implemented as:
return item is EsaTabItem
2. GetContainerForItemOverride - in your case it should be implemented as:
return new EsaTabItem();
Also the name of the inherited control should match the default style key type. I.e. you will need to have
then the default style key also needs to be:
this.DefaultStyleKey = typeof(EsaTabControl)
What is the error message that you see when you run the application?
the Telerik team