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