Method createFileChooserButton

prefs.js:764–800

(settings, key, iconName, symbolicIconName, properties)

    }

    createFileChooserButton(settings, key, iconName, symbolicIconName, properties) {
        const buttonIcon = Gtk.Image.new_from_icon_name(iconName);
        const buttonLabel = new Gtk.Label();
        const buttonBox = new Gtk.Box({
            orientation: Gtk.Orientation.HORIZONTAL,
            spacing: 8,
        });

        buttonBox.append(buttonIcon);
        buttonBox.append(buttonLabel);
        if (symbolicIconName) {
            buttonBox.append(new Gtk.Image({ icon_name: symbolicIconName, margin_start: 8 }));
        }

        const button = new Gtk.Button({ child: buttonBox });

        this.syncStringSetting(settings, key, path => {
            buttonIcon.visible = path !== '';
            buttonLabel.label = path === '' ? '(None)' : GLib.filename_display_basename(path);
        });
        button.connect('clicked', () => {
            const chooser = new Gtk.FileChooserDialog(properties);
            let path = settings.get_string(key);
            if (path !== '')
                chooser.set_file(Gio.File.new_for_path(path));
            chooser.add_button('Open', Gtk.ResponseType.OK);
            chooser.add_button('Cancel', Gtk.ResponseType.CANCEL);
            chooser.connect('response', (dialog, response) => {
                if (response === Gtk.ResponseType.OK) {
                    settings.set_string(key, chooser.get_file().get_path());
                }
                chooser.destroy();
            });
            chooser.show();
        });
        return button;
    }

    syncStringSetting(settings, key, callback) {
        settings.connect(`changed::${key}`, () => {