[pyqt5]pyqt5安装后测试代码

import sys
from PyQt5.QtWidgets import (QApplication, QWidget, QPushButton, QMessageBox, QVBoxLayout)
from PyQt5.QtCore import Qtclass MainWindow(QWidget):def __init__(self):super().__init__()self.initUI()def initUI(self):# 设置窗口标题self.setWindowTitle('helloworlddemo')# 设置窗口大小self.resize(400, 300)# 创建布局layout = QVBoxLayout()# 创建按钮self.button = QPushButton('clickme')self.button.setFixedSize(100, 40)# 连接按钮的点击信号到槽函数self.button.clicked.connect(self.showMessage)# 将按钮添加到布局中并居中layout.addStretch(1)  # 上面的弹性空间layout.addWidget(self.button, 0, Qt.AlignCenter)layout.addStretch(1)  # 下面的弹性空间# 设置布局self.setLayout(layout)def showMessage(self):# 显示消息框QMessageBox.information(self, 'Message', 'I am pyqt5 demo')if __name__ == '__main__':app = QApplication(sys.argv)window = MainWindow()window.show()sys.exit(app.exec_())

效果：