#!/usr/bin/gjs

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

const Gio = imports.gi.Gio;

const Gtk = imports.gi.Gtk;

class ToggleButtonExample {

    // Create the application itself

    constructor() {

        this.application = new Gtk.Application({

            application_id: 'org.example.jstogglebutton',

            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 window when active

    _onActivate() {

        this._window.present();

    }

    // Callback function for 'startup' signal 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,

            default_height: 300,

            default_width: 300,

            border_width: 30,

            title: "ToggleButton Example"});

        // Create the spinner that the button stops and starts

        this._spinner = new Gtk.Spinner ({hexpand: true, vexpand: true});

        // Create the togglebutton that starts and stops the spinner

        this._toggleButton = new Gtk.ToggleButton ({label: "Start/Stop"});

        this._toggleButton.connect ('toggled', this._onToggle.bind(this));

        // Create a grid and put everything in it

        this._grid = new Gtk.Grid ({

            row_homogeneous: false,

            row_spacing: 15});

        this._grid.attach (this._spinner, 0, 0, 1, 1);

        this._grid.attach (this._toggleButton, 0, 1, 1, 1);

        // Add the grid to the window

        this._window.add (this._grid);

        // Show the window and all child widgets

        this._window.show_all();

    }

    _onToggle() {

        // Start or stop the spinner

        if (this._toggleButton.get_active ())

            this._spinner.start ();

        else this._spinner.stop ();

    }

};

// Run the application

let app = new ToggleButtonExample ();

app.application.run (ARGV);