#include <CtrlLib/CtrlLib.h>

using namespace Upp;

template <class T>
struct WithFocusCallbacks : public T {
	Callback WhenGotFocus, WhenLostFocus;

	virtual void GotFocus() {
		T::GotFocus();
		WhenGotFocus();
	}

	virtual void LostFocus() {
		T::LostFocus();
		WhenLostFocus();
	}
};

class App : public TopWindow {
public:
	typedef App CLASSNAME;
	App();

	WithFocusCallbacks<EditString> text;
	EditString otherText;

	void ChangeNullText(const String& data);
};

App::App()
{
	Title("Focus callbacks example");
	CenterScreen().MinimizeBox().Sizeable();
	const Size sz(320, 240);
	SetRect(sz); SetMinSize(sz);

	text.WhenGotFocus = THISBACK1(ChangeNullText, "GotFocus");
	text.WhenLostFocus = THISBACK1(ChangeNullText, "LostFocus");

	Add(text.TopPosZ(4, 19).HSizePosZ(4, 4));
	Add(otherText.TopPosZ(27, 19).HSizePosZ(4, 4));
}

void App::ChangeNullText(const String& data)
{
	static int count = 0;
	text.NullText(Format("%s (%d)", data, ++count));
}

GUI_APP_MAIN
{
	App app;
	app.Run();
}