MainWindow.ui (Código)

<?xml version="1.0" encoding="UTF-8"?>
<!-- Generated with glade 3.38.2 -->
<interface>
    <requires lib="gtk+" version="3.24"/>
    <template class="MainWindow" parent="GtkApplicationWindow">
        <property name="can-focus">False</property>
        <property name="title" translatable="yes">Gtk.CheckButton</property>
        <property name="default-width">683</property>
        <property name="default-height">384</property>
        <property name="icon">../../../assets/icons/icon.png</property>
        <child>
            <object class="GtkBox">
                <property name="visible">True</property>
                <property name="can-focus">False</property>
                <property name="border-width">12</property>
                <property name="orientation">vertical</property>
                <property name="spacing">6</property>
                <child>
                    <object class="GtkCheckButton">
                        <property name="label" translatable="yes">Aceitar?</property>
                        <property name="visible">True</property>
                        <property name="can-focus">True</property>
                        <property name="receives-default">False</property>
                        <property name="draw-indicator">True</property>
                        <signal name="toggled" handler="on_check_button_toggled" swapped="no"/>
                    </object>
                    <packing>
                        <property name="expand">True</property>
                        <property name="fill">True</property>
                        <property name="position">0</property>
                    </packing>
                </child>
            </object>
        </child>
    </template>
</interface>