# Button (JavaScript)

Taryn Fox
jewelfox@fursona.net 2012
A button which can be connected to other widgets
Rafael Fontenelle
rafaelff@gnome.org 2013, 2018

# Button

A button widget that changes its label when you click it.

#!/usr/bin/gjs

imports.gi.versions.Gtk = '3.0';

const Gio = imports.gi.Gio; const GLib = imports.gi.GLib; const Gtk = imports.gi.Gtk;

class ButtonExample {

/* Create the application itself This boilerplate code is needed to build any GTK+ application. */ constructor() { this.application = new Gtk.Application ({ application_id: 'org.example.jsbutton', flags: Gio.ApplicationFlags.FLAGS_NONE });

// Connect 'activate' and 'startup' signals to the callback functions this.application.connect('activate', this._onActivate.bind(this)); this.application.connect('startup', this._onStartup.bind(this)); }

// Callback function for 'activate' signal presents windows when active _onActivate() { this._window.present (); }

// Callback function for 'startup' signal initializes menus and builds the UI _onStartup() { this._buildUI(); }

// Build the application's UI _buildUI() {

// Create the application window this._window = new Gtk.ApplicationWindow ({ application: this.application, window_position: Gtk.WindowPosition.CENTER, title: "GNOME Button", default_height: 50, default_width: 250 });

// Create the button this.Button = new Gtk.Button ({label: "Click Me"}); this._window.add (this.Button);

// Bind it to a function that says what to do when the button is clicked this.Button.connect ("clicked", this._clickHandler.bind(this));

// Show the window and all child widgets this._window.show_all(); }

// Here's the function that says what happens when the button is clicked _clickHandler() { this.Button.set_label ("Clicked!"); } };

// Run the application let app = new ButtonExample (); app.application.run (ARGV);

In this sample we used the following:

Gtk.Application

Gtk.ApplicationWindow

Gtk.Button