如何在pyqt5中嵌入的pyqtgraph中显示光标坐标？答案

【问题标题】：How to show cursor coordinate in pyqtgraph embedded in pyqt5?如何在pyqt5中嵌入的pyqtgraph中显示光标坐标？
【发布时间】：2021-03-27 03:10:56
【问题描述】：

我正在关注this 教程。这是嵌入在 pyqt5 中的一个简单的最小 pyqtgraphth。如何启用 pyqtgraph 在画布上显示光标坐标？

from PyQt5 import QtWidgets
from pyqtgraph import PlotWidget, plot
import pyqtgraph as pg
import sys  

class MainWindow(QtWidgets.QMainWindow):

    def __init__(self, *args, **kwargs):
        super(MainWindow, self).__init__(*args, **kwargs)

        self.graphWidget = pg.PlotWidget()
        self.setCentralWidget(self.graphWidget)

        hour = [1,2,3,4,5,6,7,8,9,10]
        temperature = [30,32,34,32,33,31,29,32,35,45]

        self.graphWidget.plot(hour, temperature)

def main():
    app = QtWidgets.QApplication(sys.argv)
    main = MainWindow()
    main.show()
    sys.exit(app.exec_())

if __name__ == '__main__':
    main()

【问题讨论】：

“显示光标位置”是什么意思？显示在哪里？怎么样？
@musicamante 我的意思是光标坐标图上的某处，它可以在右上角。

标签： python pyqt5 pyqtgraph

【解决方案1】：

试试看：

import sys
from PyQt5 import QtWidgets
from pyqtgraph import PlotWidget, plot
import pyqtgraph as pg
  

class MainWindow(QtWidgets.QMainWindow):
    def __init__(self, *args, **kwargs):
        super(MainWindow, self).__init__(*args, **kwargs)

        self.graphWidget = pg.PlotWidget()
        self.setCentralWidget(self.graphWidget)

        hour = [1,2,3,4,5,6,7,8,9,10]
        temperature = [30,32,34,32,33,31,29,32,35,45]

        self.graphWidget.plot(hour, temperature)
        
# +++ vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv
        self.label = pg.TextItem(text="Abscissa: {} \nOrdinate: {}".format(0, 0))
        self.graphWidget.addItem(self.label)
        
        self.setMouseTracking(True)
        self.graphWidget.scene().sigMouseMoved.connect(self.onMouseMoved)
        
    def onMouseMoved(self, evt):
        if self.graphWidget.plotItem.vb.mapSceneToView(evt):
            point =self.graphWidget.plotItem.vb.mapSceneToView(evt)
            self.label.setHtml(
                "<p style='color:white'>Abscissa： {0} <br> Ordinate: {1}</p>".\
                format(point.x(), point.y()))
# +++ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^


def main():
    app = QtWidgets.QApplication(sys.argv)
    main = MainWindow()
    main.show()
    sys.exit(app.exec_())

if __name__ == '__main__':
    main()

【讨论】：