显示窗口后，在构造函数中更改按钮图标

Question

我想通过构造函数方法更改按钮的图标。但它并没有像我希望的那样发生。请参阅以下代码：

demo.glade：

<?xml version="1.0" encoding="UTF-8"?>
<!-- Generated with glade 3.18.3 -->
<interface>
  <requires lib="gtk+" version="3.12"/>
  <object class="GtkImage" id="image1">
    <property name="visible">True</property>
    <property name="can_focus">False</property>
    <property name="icon_name">network-transmit-receive</property>
    <property name="icon_size">2</property>
  </object>
  <object class="GtkBox" id="box1">
    <property name="visible">True</property>
    <property name="can_focus">False</property>
    <property name="orientation">vertical</property>
    <child>
      <object class="GtkBox" id="box3">
        <property name="visible">True</property>
        <property name="can_focus">False</property>
        <child>
          <object class="GtkButtonBox" id="buttonbox1">
            <property name="visible">True</property>
            <property name="can_focus">False</property>
            <property name="orientation">vertical</property>
            <property name="layout_style">start</property>
            <child>
              <object class="GtkButton" id="button2">
                <property name="label" translatable="yes">button1</property>
                <property name="visible">True</property>
                <property name="can_focus">True</property>
                <property name="receives_default">True</property>
              </object>
              <packing>
                <property name="expand">True</property>
                <property name="fill">True</property>
                <property name="position">0</property>
              </packing>
            </child>
            <child>
              <object class="GtkButton" id="button3">
                <property name="label" translatable="yes">button2</property>
                <property name="visible">True</property>
                <property name="can_focus">True</property>
                <property name="receives_default">True</property>
              </object>
              <packing>
                <property name="expand">True</property>
                <property name="fill">True</property>
                <property name="position">1</property>
              </packing>
            </child>
            <child>
              <object class="GtkButton" id="button4">
                <property name="label" translatable="yes">button2</property>
                <property name="visible">True</property>
                <property name="can_focus">True</property>
                <property name="receives_default">True</property>
              </object>
              <packing>
                <property name="expand">True</property>
                <property name="fill">True</property>
                <property name="position">2</property>
              </packing>
            </child>
          </object>
          <packing>
            <property name="expand">False</property>
            <property name="fill">True</property>
            <property name="position">0</property>
          </packing>
        </child>
        <child>
          <placeholder/>
        </child>
      </object>
      <packing>
        <property name="expand">False</property>
        <property name="fill">True</property>
        <property name="position">0</property>
      </packing>
    </child>
    <child>
      <object class="GtkBox" id="box2">
        <property name="visible">True</property>
        <property name="can_focus">False</property>
        <child>
          <object class="GtkStatusbar" id="statusbar1">
            <property name="visible">True</property>
            <property name="can_focus">False</property>
            <property name="valign">center</property>
            <property name="margin_start">10</property>
            <property name="margin_end">10</property>
            <property name="hexpand">True</property>
            <property name="orientation">vertical</property>
            <property name="spacing">2</property>
          </object>
          <packing>
            <property name="expand">False</property>
            <property name="fill">True</property>
            <property name="position">0</property>
          </packing>
        </child>
        <child>
          <object class="GtkSpinner" id="spinner1">
            <property name="visible">True</property>
            <property name="can_focus">False</property>
            <property name="halign">center</property>
            <property name="valign">center</property>
            <property name="active">True</property>
          </object>
          <packing>
            <property name="expand">False</property>
            <property name="fill">True</property>
            <property name="position">1</property>
          </packing>
        </child>
        <child>
          <object class="GtkButton" id="button1">
            <property name="visible">True</property>
            <property name="can_focus">True</property>
            <property name="receives_default">True</property>
            <property name="halign">center</property>
            <property name="valign">center</property>
            <property name="image">image1</property>
            <property name="always_show_image">True</property>
          </object>
          <packing>
            <property name="expand">False</property>
            <property name="fill">True</property>
            <property name="position">2</property>
          </packing>
        </child>
      </object>
      <packing>
        <property name="expand">False</property>
        <property name="fill">True</property>
        <property name="position">1</property>
      </packing>
    </child>
  </object>
</interface>

demo.py

import gi

gi.require_version('Gtk','3.0')

from gi.repository import Gtk
from others.dbconnections import PgSqlConnection

class MyWind(Gtk.ApplicationWindow):

    def __init__(self, app):
        super().__init__(application=app)
        self.builder = Gtk.Builder.new_from_file('demo.glade')

        self.add(self.builder.get_object('box1'))

        if not PgSQLConnection.test():
            self.builder.get_object('image1').set_from_icon_name('network-error', Gtk.IconSize.SMALL_TOOLBAR)

        self.builder.get_object('spinner1').stop()

如果连接成功，PgSqlConnection.test()是返回True的方法，否则返回False。 但是，此方法需要几秒钟才能返回。因此只有在返回方法后才会显示窗口。 这不是我想要的行为。我想在等待方法test的返回时显示窗口。默认情况下，组件spinner1处于活动状态。 根据退货情况，button1的图标会发生变化，spinner1将被停用。 spinner1组件是一个动画，表示正在处理某些内容。