Dynamically filled combo box

[Igor Korot <ikorot01 gmail com>]

 Hi, ALL,
On Windows I have an ability to create a dynamically filled combobox.
I.e. I can catch a dropdown event (message), where I can remove all
items from the list
and insert a new string to be displayed. Then on the popup event
(message) I can remove everything and depending whether there is a
selection or not, add the appropriate string.

Is it possible to do the same with GTK+? Either with 2 or 3?

Thank you.