pyqtgraph how to get mouse click position correctly

Question

I prepared correct onMouse moved function and it shows correctly coordinates of my mouse, but when I clicked somewhere, python prints coordinates of my window not of my plot. I tried to make it the same like for the onMouseMoved but it doesn't work. I also tried to use mouseClickEvent.scenePos() instead od mouseClickEvent but it also doesn't work.

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)

        self.label = pg.TextItem(text="X: {} \nY: {}".format(0, 0))
        self.graphWidget.addItem(self.label)

        self.setMouseTracking(True)
        self.graphWidget.scene().sigMouseMoved.connect(self.onMouseMoved)
        self.graphWidget.scene().sigMouseClicked.connect(self.mouse_clicked)

    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'>X： {0} <br> Y: {1}</p>". \
                    format(point.x(), point.y()))

    def mouse_clicked(self, mouseClickEvent):
        # mouseClickEvent is a pyqtgraph.GraphicsScene.mouseEvents.MouseClickEvent
        print('clicked plot 0x{:x}, event: {}'.format(id(self), mouseClickEvent))

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


if __name__ == '__main__':
    main()

Answer 1

Asked question is very legitimate.
Indeed evt object from MouseMoused and MouseClicked is not the same.
For MouseMoved You got QPoint and for MouseClicked MouseClickEvent.

Reason for that is simple.
How would You know which mouse button was clicked, if You've got only x, y position?

So, to make things works "the same" we need to convert our MouseClickEvent into QPoint.
This can be done with evt.ScenePos()

Here is Your modified code:

import sys

import pyqtgraph as pg
from PyQt5 import QtWidgets


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)

        self.label = pg.TextItem(text="X: {} \nY: {}".format(0, 0))
        self.graphWidget.addItem(self.label)

        self.graphWidget.scene().sigMouseMoved.connect(self.mouse_moved)
        self.graphWidget.scene().sigMouseClicked.connect(self.mouse_clicked)

    def mouse_moved(self, evt):
        vb = self.graphWidget.plotItem.vb
        if self.graphWidget.sceneBoundingRect().contains(evt):
            mouse_point = vb.mapSceneToView(evt)
            self.label.setHtml(f"<p style='color:white'>X： {mouse_point.x()} <br> Y: {mouse_point.y()}</p>")

    def mouse_clicked(self, evt):
        vb = self.graphWidget.plotItem.vb
        scene_coords = evt.scenePos()
        if self.graphWidget.sceneBoundingRect().contains(scene_coords):
            mouse_point = vb.mapSceneToView(scene_coords)
            print(f'clicked plot X: {mouse_point.x()}, Y: {mouse_point.y()}, event: {evt}')


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


if __name__ == '__main__':
    main()