如何在PyQt5 ScatterPlot中使用信号

from PyQt5.QtCore import pyqtSignal
from PyQt5.QtWidgets import QApplication, QMainWindow, QSizePolicy, QVBoxLayout, QWidget
from PyQt5.QtChart import QChart, QChartView, QScatterSeries

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

        self.initUI()

    def initUI(self):
        # 设置窗口标题和大小
        self.setWindowTitle("Scatter Plot Example")
        self.resize(800, 600)

        # 创建一个布局和一个QWidget作为主窗口的中心部件
        layout = QVBoxLayout()
        central_widget = QWidget(self)
        central_widget.setLayout(layout)
        self.setCentralWidget(central_widget)

        # 创建一个QChart和QChartView，并将其添加到布局中
        chart = QChart()
        chart_view = QChartView(chart)
        layout.addWidget(chart_view)

        # 创建一个QScatterSeries，并添加数据点
        series = QScatterSeries()
        series.append(0, 0)
        series.append(1, 1)
        series.append(2, 2)

        # 将QScatterSeries添加到QChart中
        chart.addSeries(series)

        # 设置图表的标题和坐标轴标签
        chart.setTitle("Scatter Plot Example")
        chart.createDefaultAxes()

class ScatterPlot(QMainWindow):
    # 定义一个信号
    dataClicked = pyqtSignal(float, float)

    def __init__(self):
        super().__init__()

        self.initUI()

    def initUI(self):
        # ...

        # 创建一个QScatterSeries，并添加数据点
        series = QScatterSeries()
        series.append(0, 0)
        series.append(1, 1)
        series.append(2, 2)

        # 为QScatterSeries的点击事件绑定一个槽函数
        series.clicked.connect(self.handleDataClicked)

        # 将QScatterSeries添加到QChart中
        chart.addSeries(series)

        # ...

    def handleDataClicked(self, point):
        # 发射信号，并传递点击的数据点坐标
        self.dataClicked.emit(point.x(), point.y())

if __name__ == '__main__':
    app = QApplication(sys.argv)

    scatter_plot = ScatterPlot()

    # 定义一个槽函数来处理信号
    def handleDataClicked(x, y):
        print("Data clicked:", x, y)

    # 将信号与槽函数连接起来
    scatter_plot.dataClicked.connect(handleDataClicked)

    scatter_plot.show()

    sys.exit(app.exec_())