\ the GTK objects can have fields, so no global is needed
click (btn) with (label):
	btn.clicked =+ 1
	label::label text "Clicked" __ btn.clicked __ "times."
setup main window:
	win =: new GTK window
	win::set title "Button Demo"
	win::set size 150, 100
	win::connect 'destroy' to `GTK main quit`
	box =: new GTK container box 'vertical' spacing 2
	win::add container box
	msg =: new GTK widget label "Not yet any click, click the button..."
	box::add widget msg
	button =: new GTK widget button "Click here"
	button.clicked =: 0
	button::connect 'clicked' to `click () with ()` with msg
	box::add widget button
	win::show all
	:>win

main (args):+
	GTK init args
	GTK main setup main window