gtk3 GTK+ 3 with Vala Hello world

Example

Could be even more basic, but this showcases some of the features the Vala language.

The code

using Gtk; int main (string[] args) { Gtk.init (ref args); var window = new Window (); window.title = "First GTK+ Program"; window.border_width = 10; window.window_position = WindowPosition.CENTER; window.set_default_size (350, 70); window.destroy.connect (Gtk.main_quit); var button = new Button.with_label ("Click me!"); button.clicked.connect (() => { button.label = "Thank you"; }); window.add (button); window.show_all (); Gtk.main (); return 0; } 

All GTK+ classes are inside the Gtk namespace. You must initialize every GTK+ program with Gtk.init ().

Compilation and Running on Linux

$ valac --pkg gtk+-3.0 gtk-hello.vala $ ./gtk-hello 

This needs the valac compiler, gcc, the glib and gtk3 development packages installed on your system.

Taken from the GNOME Wiki.

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