gtkmm.cpp

// g++ -std=c++11 `pkg-config gtkmm-2.4 --cflags --libs` -o gtkmm gtkmm.cpp

#include <gtkmm/drawingarea.h>
#include <gtkmm/main.h>
#include <gtkmm/window.h>
#include <cairomm/context.h>

class IchimatsuArea : public Gtk::DrawingArea
{
public:
  IchimatsuArea() {}
  virtual ~IchimatsuArea() {}
protected:
  virtual bool on_expose_event(GdkEventExpose* event) {
    auto window = get_window();
    if (window) {
      auto allocation = get_allocation();
      const int width = allocation.get_width();
      const int height = allocation.get_height();
      const int cell_width = width / 20;
      const int cell_height = height / 20;
      auto cr = window->create_cairo_context();
      cr->set_source_rgb(0.8, 0.0, 0.0);
      for (int i=0; i<400; ++i) {
	int x = i % 20;
	int y = i / 20;
	if ((x+y) % 2 == 0) {
	  cr->rectangle(x * cell_width, y * cell_height, cell_width, cell_height);
	}
      }
      cr->fill();
    }
    return true;
  }
};

int main(int argc, char** argv)
{
   Gtk::Main kit(argc, argv);

   Gtk::Window win;
   win.set_title("DrawingArea");

   IchimatsuArea area;
   win.add(area);
   area.show();

   Gtk::Main::run(win);

   return 0;
}