#include <FL/Fl_Window.H>
#include <FL/Fl_Input.H>
#include <FL/Fl.H>
#include <FL/x.H>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

class Fl_Embed_Window:public Fl_Window
{
public:
	Window xid_;
	Fl_Embed_Window(int ix,int iy,Window xid):Fl_Window(ix,iy,0,0)
	{
		xid_ = xid;
	}
	
	void show(void)
	{
		XWindowAttributes attribs;
 		XGetWindowAttributes(fl_display, xid_, &attribs);
		if (shown()) {
			Fl_Window::show();
			return;
		}
		Fl_X::set_xid(this, xid_);
		size(attribs.width,attribs.height);
		XReparentWindow (fl_display, xid_, fl_xid(window()), 0, 0);
	}
};

void embed(Fl_Widget* widget,void* ptr)
{
	Fl_Input* input = (Fl_Input*) widget;
	Fl_Window* window = widget->window();
	Fl_Window* embedded;
	char tmp[256];
	int xid;
	strncpy(tmp,input->value(),255);
	
	sscanf(tmp,"%x",&xid);

	window->add(embedded = new Fl_Embed_Window(0,0,xid));
	embedded->show(); // cause the reparent
}

main()
{
	Fl_Window window(400,400);
	Fl_Input input(0,380,400,20);
	input.when(FL_WHEN_ENTER_KEY);
	input.callback(embed);
	window.end();
	window.resizable(window);
	window.show();
	Fl::run();
}