This is a known problem in RadComboBox, which will be addressed in the upcoming update of RadControls for Silverlight next week. I already changed the control behavior as follows:
- before: the dropdown opens when you start typing
- now: the dropdown opens when the textbox receives focus, but only if the filtering is enabled. I was thinking about adding a new property OpenDropDownOnFocus, or something similar, which will make clear to the developer when is the dropdown opened, but for now I decided to leave the control as it is.
I will be glad to get your feedback about how do you expect it to behave when the filtering is enabled.
Regarding the second question - I was not able to reproduce the problem and I think that it is not normal to inherit the control, just to let the dropdown to open when you start typing. I suppose that the problem will disappear when you upgrade the control to the version we will release next tuesday.
Your points have been updated.
Valeri Hristov (Silverlight Team)
the Telerik team
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