#include using namespace Upp; struct MyAppWindow : TopWindow { void Paint(Draw& w) override { w.DrawRect(GetSize(), SWhite()); w.DrawText(20, 20, "Hello world!", Arial(30), Magenta); } MyAppWindow() { Title("My application").Zoomable().Sizeable(); } }; GUI_APP_MAIN { MyAppWindow app; app.SetRect(0, 0, 400, 100); app.Run(); }