This is a bare bones sample visual that demonstrates what you need to create your own slicer using the Power BI Custom Visual SDK. A "slicer" is a control that allows you to filter a report based on a selected value.
The "Radio Slicer" control simply renders a radio button for every category databound to it. When you click on a radio button the rest of the report will be filtered by that radio button's value.
If you'd like to just use this visual, then you can download it here: Download Radio Slicer
If you want to learn how to create your own slicer, you can follow along at this blog post: How to Create a Power BI Slicer with the Power BI Custom Visual SDK
I intentionally made this as simple as possible to demonstrate what is required to create a custom slicer. I also created a more complete slicer example that can be found here: PowerBI-visuals-rangeSlider.