QObject类型判定案例

import sys
from PySide2 import QtWidgets as qtw

app = qtw.QApplication()

window = qtw.QWidget()
label_1 = qtw.QLabel(window)
label_1.setText('安静一键宏')

label_2 = qtw.QLabel(window)
label_2.setText('轻松玩魔兽')
label_2.move(0, 30)

btn = qtw.QPushButton(window)
btn.setText('点我')
btn.move(0, 60)

# .children() 方法只是返回所有的子对象，没有findChildren的过滤功能
for item in window.children():
    if item.inherits('QLabel'):
        item.setStyleSheet('background-color: red;')

window.show()

sys.exit(app.exec_())