.ui文件是用Qt Designer设计的界面保存后的文件；
保存后我们需要把这个文件转换成.py 文件，才能进行运行。

1 使用Qt Designer设计一个简单的界面

设计如下一个界面：
保存为question.ui,保存工程目录下即可：
UI文件的源码为以下，其实是一个xml格式文件：

<?xml version="1.0" encoding="UTF-8"?>
<ui version="4.0">
 <class>MainWindow</class>
 <widget class="QMainWindow" name="MainWindow">
  <property name="geometry">
   <rect>
    <x>0</x>
    <y>0</y>
    <width>366</width>
    <height>324</height>
   </rect>
  </property>
  <property name="windowTitle">
   <string>问卷调查</string>
  </property>
  <widget class="QWidget" name="centralwidget">
   <widget class="QRadioButton" name="radioButton">
    <property name="geometry">
     <rect>
      <x>20</x>
      <y>30</y>
      <width>86</width>
      <height>21</height>
     </rect>
    </property>
    <property name="text">
     <string>A、Python</string>
    </property>
    <property name="checked">
     <bool>false</bool>
    </property>
   </widget>
   <widget class="QLabel" name="label">
    <property name="geometry">
     <rect>
      <x>10</x>
      <y>10</y>
      <width>171</width>
      <height>16</height>
     </rect>
    </property>
    <property name="text">
     <string>1、你最喜欢的编程语言是（D）</string>
    </property>
   </widget>
   <widget class="QRadioButton" name="radioButton_2">
    <property name="geometry">
     <rect>
      <x>20</x>
      <y>60</y>
      <width>86</width>
      <height>21</height>
     </rect>
    </property>
    <property name="text">
     <string>B、C</string>
    </property>
    <property name="checked">
     <bool>false</bool>
    </property>
   </widget>
   <widget class="QRadioButton" name="radioButton_3">
    <property name="geometry">
     <rect>
      <x>20</x>
      <y>90</y>
      <width>86</width>
      <height>21</height>
     </rect>
    </property>
    <property name="text">
     <string>C、Go</string>
    </property>
    <property name="checked">
     <bool>false</bool>
    </property>
   </widget>
   <widget class="QRadioButton" name="radioButton_4">
    <property name="enabled">
     <bool>true</bool>
    </property>
    <property name="geometry">
     <rect>
      <x>20</x>
      <y>120</y>
      <width>86</width>
      <height>21</height>
     </rect>
    </property>
    <property name="text">
     <string>D、Java</string>
    </property>
    <property name="checked">
     <bool>true</bool>
    </property>
   </widget>
   <widget class="QRadioButton" name="radioButton_5">
    <property name="geometry">
     <rect>
      <x>20</x>
      <y>180</y>
      <width>86</width>
      <height>21</height>
     </rect>
    </property>
    <property name="text">
     <string>A、苹果</string>
    </property>
    <property name="checked">
     <bool>false</bool>
    </property>
   </widget>
   <widget class="QRadioButton" name="radioButton_6">
    <property name="geometry">
     <rect>
      <x>20</x>
      <y>270</y>
      <width>86</width>
      <height>21</height>
     </rect>
    </property>
    <property name="text">
     <string>D、葡萄</string>
    </property>
    <property name="checked">
     <bool>false</bool>
    </property>
   </widget>
   <widget class="QRadioButton" name="radioButton_7">
    <property name="geometry">
     <rect>
      <x>20</x>
      <y>240</y>
      <width>86</width>
      <height>21</height>
     </rect>
    </property>
    <property name="text">
     <string>C、梨</string>
    </property>
    <property name="checked">
     <bool>false</bool>
    </property>
   </widget>
   <widget class="QLabel" name="label_2">
    <property name="geometry">
     <rect>
      <x>10</x>
      <y>160</y>
      <width>221</width>
      <height>16</height>
     </rect>
    </property>
    <property name="text">
     <string>2、请选择你最喜欢的水果（）</string>
    </property>
   </widget>
   <widget class="QRadioButton" name="radioButton_8">
    <property name="geometry">
     <rect>
      <x>20</x>
      <y>210</y>
      <width>86</width>
      <height>21</height>
     </rect>
    </property>
    <property name="text">
     <string>B、香蕉</string>
    </property>
    <property name="checked">
     <bool>false</bool>
    </property>
   </widget>
  </widget>
  <widget class="QStatusBar" name="statusbar"/>
 </widget>
 <resources/>
 <connections/>
</ui>

在这里插入图片描述

2 UI文件转PY文件

2.1 方法一：直接使用命令

直接在命令行输入以下命令即可：

python -m PyQt5.uic.pyuic question.ui -o question.py

可以发现在question.ui同目录生成了一个question.py文件
2.2 方法二：直接调用PyUIC5工具
直接依次点击pycharm-工具-EXternal Tools-PyUIC即可：
可以达到相同的效果：
从图片中看，其实效果也是使用命令来运行的，一个直接输入命令，一个调用PyUIC工具来运行。

3 运行转换后的py文件

先看下question.py文件代码：

# -*- coding: utf-8 -*-

# Form implementation generated from reading ui file 'question.ui'
#
# Created by: PyQt5 UI code generator 5.15.4
#
# WARNING: Any manual changes made to this file will be lost when pyuic5 is
# run again.  Do not edit this file unless you know what you are doing.


from PyQt5 import QtCore, QtGui, QtWidgets


class Ui_MainWindow(object):
    def setupUi(self, MainWindow):
        MainWindow.setObjectName("MainWindow")
        MainWindow.resize(366, 324)
        self.centralwidget = QtWidgets.QWidget(MainWindow)
        self.centralwidget.setObjectName("centralwidget")
        self.radioButton = QtWidgets.QRadioButton(self.centralwidget)
        self.radioButton.setGeometry(QtCore.QRect(20, 30, 86, 21))
        self.radioButton.setChecked(False)
        self.radioButton.setObjectName("radioButton")
        self.label = QtWidgets.QLabel(self.centralwidget)
        self.label.setGeometry(QtCore.QRect(10, 10, 171, 16))
        self.label.setObjectName("label")
        self.radioButton_2 = QtWidgets.QRadioButton(self.centralwidget)
        self.radioButton_2.setGeometry(QtCore.QRect(20, 60, 86, 21))
        self.radioButton_2.setChecked(False)
        self.radioButton_2.setObjectName("radioButton_2")
        self.radioButton_3 = QtWidgets.QRadioButton(self.centralwidget)
        self.radioButton_3.setGeometry(QtCore.QRect(20, 90, 86, 21))
        self.radioButton_3.setChecked(False)
        self.radioButton_3.setObjectName("radioButton_3")
        self.radioButton_4 = QtWidgets.QRadioButton(self.centralwidget)
        self.radioButton_4.setEnabled(True)
        self.radioButton_4.setGeometry(QtCore.QRect(20, 120, 86, 21))
        self.radioButton_4.setChecked(True)
        self.radioButton_4.setObjectName("radioButton_4")
        self.radioButton_5 = QtWidgets.QRadioButton(self.centralwidget)
        self.radioButton_5.setGeometry(QtCore.QRect(20, 180, 86, 21))
        self.radioButton_5.setChecked(False)
        self.radioButton_5.setObjectName("radioButton_5")
        self.radioButton_6 = QtWidgets.QRadioButton(self.centralwidget)
        self.radioButton_6.setGeometry(QtCore.QRect(20, 270, 86, 21))
        self.radioButton_6.setChecked(False)
        self.radioButton_6.setObjectName("radioButton_6")
        self.radioButton_7 = QtWidgets.QRadioButton(self.centralwidget)
        self.radioButton_7.setGeometry(QtCore.QRect(20, 240, 86, 21))
        self.radioButton_7.setChecked(False)
        self.radioButton_7.setObjectName("radioButton_7")
        self.label_2 = QtWidgets.QLabel(self.centralwidget)
        self.label_2.setGeometry(QtCore.QRect(10, 160, 221, 16))
        self.label_2.setObjectName("label_2")
        self.radioButton_8 = QtWidgets.QRadioButton(self.centralwidget)
        self.radioButton_8.setGeometry(QtCore.QRect(20, 210, 86, 21))
        self.radioButton_8.setChecked(False)
        self.radioButton_8.setObjectName("radioButton_8")
        MainWindow.setCentralWidget(self.centralwidget)
        self.statusbar = QtWidgets.QStatusBar(MainWindow)
        self.statusbar.setObjectName("statusbar")
        MainWindow.setStatusBar(self.statusbar)

        self.retranslateUi(MainWindow)
        QtCore.QMetaObject.connectSlotsByName(MainWindow)

    def retranslateUi(self, MainWindow):
        _translate = QtCore.QCoreApplication.translate
        MainWindow.setWindowTitle(_translate("MainWindow", "问卷调查"))
        self.radioButton.setText(_translate("MainWindow", "A、Python"))
        self.label.setText(_translate("MainWindow", "1、你最喜欢的编程语言是（D）"))
        self.radioButton_2.setText(_translate("MainWindow", "B、C"))
        self.radioButton_3.setText(_translate("MainWindow", "C、Go"))
        self.radioButton_4.setText(_translate("MainWindow", "D、Java"))
        self.radioButton_5.setText(_translate("MainWindow", "A、苹果"))
        self.radioButton_6.setText(_translate("MainWindow", "D、葡萄"))
        self.radioButton_7.setText(_translate("MainWindow", "C、梨"))
        self.label_2.setText(_translate("MainWindow", "2、请选择你最喜欢的水果（）"))
        self.radioButton_8.setText(_translate("MainWindow", "B、香蕉"))

生成的代码是不能直接运行的，需要进行调用；
我们再写一个主函数来调用这个py文件，比如main.py,代码如下：

# -*- coding:utf-8 -*-
# 作者：虫无涯
# 日期：2023/8/25
# 文件名称：main.py
# 作用：主程序入口
# 联系：VX(NoamaNelson)
# 博客：https://blog.csdn.net/NoamaNelson

import sys
from test_case.question import Ui_MainWindow
from PyQt5.QtWidgets import QApplication, QWidget, QMainWindow


if __name__ == "__main__":
    app = QApplication(sys.argv)
    window = QMainWindow()
    ui = Ui_MainWindow()
    ui.setupUi(window)
    window.resize(400, 400)
    window.show()

    sys.exit(app.exec_())