1. 安装

Python环境：3.7.3

1. 从PyPi下载安装：
   pip install PySide2 # For the latest version on PyPi
2. 通过http下载安装：
   pip install --index-url=http://download.qt.io/snapshots/ci/pyside/5.12/latest pyside2 --trusted-host download.qt.io

2. 测试是否安装成功

import PySide2.QtCore

# Prints PySide2 version
print(PySide2.__version__)
# 5.12.2

# Gets a tuple with each version component
print(PySide2.__version_info__)
# (5, 12, 2, '', '')

# Prints the Qt version used to compile PySide2
print(PySide2.QtCore.__version__)
# 5.12.2

# Gets a tuple with each version components of Qt used to compile PySide2
print(PySide2.QtCore.__version_info__)
# (5, 12, 2)

# Print the current running Qt version number
print(PySide2.QtCore.qVersion())
# 5.12.2

3. Hello world！

import sys
import random
from PySide2 import QtCore, QtWidgets, QtGui

# Define a class named MyWidget, 
# which extends QWidget and includes a QPushButton and QLabel
class MyWidget(QtWidgets.QWidget):
    def __init__(self):
        super().__init__()

        self.hello = ["你好，世界", "Hallo Welt", "Hei maailma", "Hola Mundo", "Привет мир"]

        self.button = QtWidgets.QPushButton("Click me!")
        self.text = QtWidgets.QLabel("Hello World")
        self.text.setAlignment(QtCore.Qt.AlignCenter)

        self.layout = QtWidgets.QVBoxLayout()
        self.layout.addWidget(self.text)
        self.layout.addWidget(self.button)
        self.setLayout(self.layout)

        self.button.clicked.connect(self.magic)

    def magic(self):
        self.text.setText(random.choice(self.hello))


if __name__ == "__main__":
    app = QtWidgets.QApplication([])

    widget = MyWidget()
    widget.resize(800, 600)
    widget.show()

    sys.exit(app.exec_())