2. Using Events and Callbacks | Interactive Applications using Matplotlib

Making the connection

The callback system is figure-oriented. Any GUI action that can trigger a callback can only happen to whichever figure window is currently in focus. There are no global actions that can trigger callbacks across multiple figures. The callback function will get an Event object that contains pertinent information about the fired event. In the following example, we will hook up two events to a figure: a keyboard button press and a mouse button press. There are two callback functions, each printing out some of the available pieces of information for their respective events:

Code: chp2/basic_mpl_connect.py

from __future__ import print_function 
import matplotlib.pyplot as plt 

def process_key(event): 
    print("Key:", event.key) 
def process_button(event): 
    print("Button:", event.x, event.y, event.xdata, event.ydata, event.button) 

fig, ax = plt.subplots(1, 1) 
fig.canvas.mpl_connect('key_press_event', process_key) 
fig.canvas.mpl_connect('button_press_event', process_button...

Tech Concepts

Programming languages

Tech Tools

Unlimited access to the largest independent learning library in tech of over 8,000 expert-authored tech books and videos.

Innovative learning tools, including AI book assistants, code context explainers, and text-to-speech.

50+ new titles added per month and exclusive early access to books as they are being written.

Interactive Applications using Matplotlib

Interactive Applications using Matplotlib

Overview of this book

Making the connection

Confirmation

Buy this book with your credits?

Submit Your Feedback

Create a Free Account To Continue Reading

Sign in to activate your 7-day free access