NoneType ERROR

[Wahabo Ouedraogo]

if i run this code i get the following error which i don't understand:

Traceback (most recent call last):

   File "d: \ PyQt \ VS Code \ crosshair_example.py", line 45, in <module>

     Plot_Item.scene (). SigMouseMoved.connect (mouseMoved)

AttributeError: 'NoneType' object has no attribute 'sigMouseMoved'

PS D: \ PlattFomio Projects \ Arduino Memory Project>

This is the code : 

import numpy as np

import pyqtgraph as pg

from pyqtgraph.Qt import QtGui, QtCore

from pyqtgraph.Point import Point

from pyqtgraph.graphicsItems import PlotItem

import sys

app = pg.mkQApp("Crosshair Example")

data1 = 10000 + 15000 * pg.gaussianFilter(np.random.random(size=100), 10) + 3000 * np.random.random(size=100)

Plot_Item = pg.PlotItem()

label = pg.LabelItem(justify='right')

Plot_Item.addItem(label)

Plot_Item.plot(data1)

vLine = pg.InfiniteLine(angle=90, movable = False)

hLine = pg.InfiniteLine(angle=0, movable= False)

Plot_Item.addItem(vLine, ignoreBounds=True)

Plot_Item.addItem(hLine, ignoreBounds=True)

vb = Plot_Item.vb

def mouseMoved(evt):

    pos = evt

    if Plot_Item.sceneBoundingRect().contains(pos):

        mousePoint = vb.mapSceneToView(pos)

        index = int(mousePoint.x())

        if index > 0 and index < len(data1):

            label.setText("<span style='font-size: 12pt'>x=%0.1f,   <span style='color: red'>y1=%0.1f</span>,   <span style='color: green'>y2=%0.1f</span>" % (mousePoint.x(), data1[index], data2[index]))

        vLine.setPos(mousePoint.x())

        hLine.setPos(mousePoint.y())  

           

Plot_Item.scene().sigMouseMoved.connect(mouseMoved)

if __name__ == '__main__':

    pg.exec()

[Ognyan Moore]

Hi, sorry I didn't reply earlier, you might have to call Plot_Item.show() first so the scene gets generated/attached.

[Wahabo Ouedraogo]

Thank you very much, the problem is solved