struct DragTest : TopWindow {
	Rect r;
	bool dragging = false;
	void Layout() override {
		r = GetRect();
	};

	void Paint(Draw& w) override {
		w.DrawRect(GetSize(), White());
		w.DrawText(100, 100, AsString(r));
		if(dragging)
			w.DrawText(100, 130, "Dragging");
	}
	
	TimeCallback tm;
	
	DragTest() {
		tm.Set(-10, [=] {
			Rect rr = GetRect();
			if(r != rr) {
				r = rr;
				if(GetMouseLeft())
					dragging = true;
				Refresh();
			}
			if(!GetMouseLeft()) {
				if(dragging) {
					dragging = false;
					Refresh();
				}
			}
		});
	}
};