QGraphicsView绘制同心圆弧

可以通过在QGraphicsView中使用QPainter绘制同心圆弧。

以下是一个示例代码，绘制3个同心圆弧：

from PyQt5.QtWidgets import QGraphicsView, QGraphicsScene
from PyQt5.QtGui import QPainter, QColor, QPen, QBrush
from PyQt5.QtCore import Qt

class MyGraphicsView(QGraphicsView):
    def __init__(self, parent=None):
        super(MyGraphicsView, self).__init__(parent)
        self.scene = QGraphicsScene(self)
        self.setScene(self.scene)

    def paintEvent(self, event):
        painter = QPainter(self.viewport())

        # 绘制第一个圆弧
        pen = QPen(QColor(255, 0, 0))
        pen.setWidth(5)
        brush = QBrush(QColor(255, 0, 0, 50))
        painter.setPen(pen)
        painter.setBrush(brush)
        painter.drawArc(50, 50, 200, 200, 0 * 16, 90 * 16)

        # 绘制第二个圆弧
        pen = QPen(QColor(0, 255, 0))
        pen.setWidth(5)
        brush = QBrush(QColor(0, 255, 0, 50))
        painter.setPen(pen)
        painter.setBrush(brush)
        painter.drawArc(75, 75, 150, 150, 0 * 16, 90 * 16)

        # 绘制第三个圆弧
        pen = QPen(QColor(0, 0, 255))
        pen.setWidth(5)
        brush = QBrush(QColor(0, 0, 255, 50))
        painter.setPen(pen)
        painter.setBrush(brush)
        painter.drawArc(100, 100, 100, 100, 0 * 16, 90 * 16)

if __name__ == '__main__':
    import sys
    from PyQt5.QtWidgets import QApplication

    app = QApplication(sys.argv)
    view = MyGraphicsView()
    view.show()
    sys.exit(app.exec_())

在这个示例中，使用QPen和QBrush来设置圆弧的颜色和填充颜色。使用drawArc方法绘制圆弧，其中设置了圆弧的起始角度和角度范围。可以根据需要调整这些参数来绘制不同的圆弧。