How to populate Add-In Combo Box with attributes

Hello,
I'm using ArcMap 10.2 and trying to populate an Add-In Combo Box with the attributes (SampleYear)0 of a layer (Stream_Temperatures). Then, on selection of a year in the Combo Box, have those records selected.

The steps I've identified are as follows

1) Identify and get values from the selected attribute (SampleYear) of Layer (layer = Stream_Temperatures)
2) Display these selected years in a Combo Box
3) On user selection of year, select this year in feature class

I'm new to Python and programming and would love any thoughts or suggestions.

Thanks,
Katie