Pyqt5 简明教程

PyQt5 - Using Qt Designer

PyQt 安装程序附带了一个名为 Qt Designer 的 GUI 构建工具。利用其简单的拖放界面，可以快速构建 GUI 界面而无需编写代码。然而，它不是像 Visual Studio 这样的 IDE。因此，Qt Designer 没有调试和构建应用程序的功能。

The PyQt installer comes with a GUI builder tool called Qt Designer. Using its simple drag and drop interface, a GUI interface can be quickly built without having to write the code. It is however, not an IDE such as Visual Studio. Hence, Qt Designer does not have the facility to debug and build the application.

启动 Qt Designer 应用程序，该应用程序是一个开发工具的一部分，安装在虚拟环境的脚本文件夹中。

Start Qt Designer application which is a part of development tools and installed in scripts folder of the virtual environment.

virtual environment

通过选择 File → New 菜单开始设计 GUI 界面。

Start designing GUI interface by choosing File → New menu.

new menu

然后，您可以从左侧窗格中的小部件框中拖放所需の小部件。您还可以将值分配给布置在窗体上的小部件的属性。

You can then drag and drop required widgets from the widget box on the left pane. You can also assign value to properties of widget laid on the form.

widget

设计的表单保存为 demo.ui。该 ui 文件包含小部件及其在设计中的属性的 XML 表示。此设计通过使用 pyuic5 命令行实用程序转换为等效 Python。该实用程序是 Qt 工具包的 uic 模块的一个包装器。pyuic5 的用法如下 −

The designed form is saved as demo.ui. This ui file contains XML representation of widgets and their properties in the design. This design is translated into Python equivalent by using pyuic5 command line utility. This utility is a wrapper for uic module of Qt toolkit. The usage of pyuic5 is as follows −

pyuic5 -x demo.ui -o demo.py

在上面的命令中，-x 交换机向生成的 Python 脚本（从 XML）添加少量的附加代码，使其成为可独立执行的独立应用程序。

In the above command, -x switch adds a small amount of additional code to the generated Python script (from XML) so that it becomes a self-executable standalone application.

if __name__ == "__main__":
   import sys
   app = QtGui.QApplication(sys.argv)
   Dialog = QtGui.QDialog()
   ui = Ui_Dialog()
   ui.setupUi(Dialog)
   Dialog.show()
   sys.exit(app.exec_())

执行结果 Python 脚本以显示以下对话框 −

The resultant python script is executed to show the following dialog box −

python demo.py
dialog box

用户可以在输入字段中输入数据，但单击“添加”按钮不会生成任何操作，因为它不与任何函数关联。对用户生成的响应作出反应被称为 event handling 。

The user can input data in input fields but clicking on Add button will not generate any action as it is not associated with any function. Reacting to user-generated response is called as event handling.