Shows how to create a radio round button with Fl_Round_Button widget.
To build this project, open "Terminal" and type following lines:
mkdir build && cd build
cmake ..
start Round_Button.sln
Select Round_Button project and type Ctrl+F5 to build and run it.
mkdir build && cd build
cmake .. -G "Xcode"
open ./Round_Button.xcodeproj
Select Round_Button project and type Cmd+R to build and run it.
mkdir build && cd build
cmake ..
cmake --build . --config Debug
./Round_Button