使用不同颜色的pyqt5标记线条

from PyQt5.QtWidgets import QApplication, QMainWindow, QWidget, QVBoxLayout
from PyQt5.QtGui import QPainter, QColor, QPen
from PyQt5.QtCore import Qt

class MyWindow(QMainWindow):
    def __init__(self):
        super().__init__()

        self.initUI()

    def initUI(self):
        # 设置窗口标题和大小
        self.setWindowTitle("Colorful Lines")
        self.setGeometry(100, 100, 500, 400)

        # 创建一个自定义的小部件，并将其设置为主窗口的中央部分
        widget = MyWidget(self)
        self.setCentralWidget(widget)

class MyWidget(QWidget):
    def paintEvent(self, event):
        # 创建一个QPainter对象
        painter = QPainter(self)

        # 创建一个QPen对象，并设置线条颜色、粗细和风格
        pen = QPen()
        pen.setWidth(2)

        # 绘制红色线条
        pen.setColor(QColor(255, 0, 0))
        painter.setPen(pen)
        painter.drawLine(50, 50, 250, 50)

        # 绘制绿色线条
        pen.setColor(QColor(0, 255, 0))
        painter.setPen(pen)
        painter.drawLine(50, 100, 250, 100)

        # 绘制蓝色线条
        pen.setColor(QColor(0, 0, 255))
        painter.setPen(pen)
        painter.drawLine(50, 150, 250, 150)

        # 绘制黄色线条
        pen.setColor(QColor(255, 255, 0))
        painter.setPen(pen)
        painter.drawLine(50, 200, 250, 200)

if __name__ == '__main__':
    app = QApplication([])
    window = MyWindow()
    window.show()
    app.exec_()