简单方式

不传递参数

import os
import sys

import PySide2
from PySide2.QtWidgets import QApplication, QPushButton

dirname = os.path.dirname(PySide2.__file__)
plugin_path = os.path.join(dirname, 'plugins', 'platforms')
os.environ['QT_QPA_PLATFORM_PLUGIN_PATH'] = plugin_path

# 槽函数
def sayHello():
    print("Hello World!")

# Create the Qt Application
app = QApplication(sys.argv)
# Create a button, connect it and show it
button = QPushButton("Click me")
# 点击事件连接槽函数
button.clicked.connect(sayHello)
button.show()
# Run the main Qt loop
app.exec_()

传递参数

定义带有形参的槽函数

# 槽函数，有形参
def sayHello(arg):
    print("Hello World!",arg)

方式一

通过 lambda 表达式

button.clicked.connect(lambda : sayHello(1))

方式二

使用functools里的partial函数

button.clicked.connect(partial(sayHello, 1))

完整代码

import os
import sys

import PySide2
from PySide2.QtWidgets import QApplication, QPushButton

dirname = os.path.dirname(PySide2.__file__)
plugin_path = os.path.join(dirname, 'plugins', 'platforms')
os.environ['QT_QPA_PLATFORM_PLUGIN_PATH'] = plugin_path

# 槽函数，有形参
def sayHello(arg):
    print("Hello World!",arg)

# Create the Qt Application
app = QApplication(sys.argv)
# Create a button, connect it and show it
button = QPushButton("Click me")
# 点击事件连接槽函数，通过lambda方式传参
# button.clicked.connect(lambda : sayHello(1))
button.clicked.connect(lambda : sayHello(1))
button.show()
# Run the main Qt loop
app.exec_()