.. _event_handling-legend_picking: event_handling example code: legend_picking.py ============================================== [`source code `_] :: """ Enable picking on the legend to toggle the legended line on and off """ import numpy as np import matplotlib.pyplot as plt t = np.arange(0.0, 0.2, 0.1) y1 = 2*np.sin(2*np.pi*t) y2 = 4*np.sin(2*np.pi*2*t) fig, ax = plt.subplots() ax.set_title('Click on legend line to toggle line on/off') line1, = ax.plot(t, y1, lw=2, color='red', label='1 HZ') line2, = ax.plot(t, y2, lw=2, color='blue', label='2 HZ') leg = ax.legend(loc='upper left', fancybox=True, shadow=True) leg.get_frame().set_alpha(0.4) # we will set up a dict mapping legend line to orig line, and enable # picking on the legend line lines = [line1, line2] lined = dict() for legline, origline in zip(leg.get_lines(), lines): legline.set_picker(5) # 5 pts tolerance lined[legline] = origline def onpick(event): # on the pick event, find the orig line corresponding to the # legend proxy line, and toggle the visibility legline = event.artist origline = lined[legline] vis = not origline.get_visible() origline.set_visible(vis) # Change the alpha on the line in the legend so we can see what lines # have been toggled if vis: legline.set_alpha(1.0) else: legline.set_alpha(0.2) fig.canvas.draw() fig.canvas.mpl_connect('pick_event', onpick) plt.show() Keywords: python, matplotlib, pylab, example, codex (see :ref:`how-to-search-examples`)