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.Dialog() custom</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>
        <child>
          <object class="GtkButton" id="button">
            <property name="label" translatable="yes">Abrir janela de dialogo</property>
            <property name="visible">True</property>
            <property name="can_focus">True</property>
            <property name="receives_default">True</property>
            <signal name="clicked" handler="open_dialog" swapped="no"/>
          </object>
          <packing>
            <property name="expand">False</property>
            <property name="fill">True</property>
            <property name="position">0</property>
          </packing>
        </child>
        <child>
          <object class="GtkLabel" id="label">
            <property name="visible">True</property>
            <property name="can_focus">False</property>
            <property name="label" translatable="yes">Valor digitado no dialogo:</property>
          </object>
          <packing>
            <property name="expand">True</property>
            <property name="fill">True</property>
            <property name="position">1</property>
          </packing>
        </child>
      </object>
    </child>
    <child type="titlebar">
      <placeholder/>
    </child>
  </template>
</interface>