#include <CtrlLib/CtrlLib.h>

using namespace Upp;

struct MyApp : TopWindow {
	TabCtrl tabs;
	ParentCtrl pctrl;
	Button bt;
	MyApp()
	{
		Sizeable().Zoomable().CenterScreen().SetRect(0, 0, 640, 480);
		Title("Window Title"); // Sets the window title.
		tabs.Add(pctrl.SizePos(), "Tab1");
		pctrl.Add(bt.SetLabel("Change Title (and button label)").HCenterPos(400).VCenterPos(100));
		Add(tabs.SizePos());
		bt << [=] {
			auto *w = GetTopWindow();
			if(w) {
				String s = w->GetTitle().ToString(); // Get top window's title
				w->Title(bt.GetLabel()); // set the top window's title
				bt.SetLabel(s); //swap the label with the current window title.
			}
		};
	}
};

GUI_APP_MAIN
{
	MyApp().Run();
}