Python: how to get coordinates on mouse click using matplotlib.canvas

coordinates, matplotlib, python

Solution

Your code works for me, as long as I insert `plt.show()` after `mpl_connect` in `getCoord`:

def getCoord(self):
    fig = plt.figure()
    ax = fig.add_subplot(111)
    plt.imshow(self.img)
    cid = fig.canvas.mpl_connect('button_press_event', self.__onclick__)
    plt.show()
    return self.point

Problem

I am writing a class to process images. In that class, I want to define a method that can allow me to return coordinates of the mouse clicks. I can get the coordinates as an attribute but if I call the method to return the coordinates, I get an empty tuple Here is the code: ``` import cv2 import matplotlib.pyplot as plt class TestClass(): def __init__(self): self.fname = 'image.jpg' self.img = cv2.imread(self.fname) self.point = () def getCoord(self): fig = plt.figure() ax = fig.add_subplot(111) plt.imshow(self.img) cid = fig.canvas.mpl_connect('button_press_event', self.__onclick__) return self.point def __onclick__(self,click): self.point = (click.xdata,click.ydata) return self.point ```

Original source