在PyQt中禁用matplotlib小部件

Question

I have a pyQt application with several embedded matplotlib widgets ( https://github.com/chipmuenk/pyFDA ).

The automatic updating of plots can be turned off for each plotting widget to speed up the application (especially 3D plots can take quite long).

Unfortunately, I haven't managed to disable (grey out) the canvas completely yet. What I'd like is to do something like

class MplWidget(QWidget):
    """
    Construct a subwidget with Matplotlib canvas and NavigationToolbar
    """

    def __init__(self, parent):
        super(MplWidget, self).__init__(parent)
        # Create the mpl figure and construct the canvas with the figure
        self.fig = Figure()
        self.pltCanv = FigureCanvas(self.fig)
#-------------------------------------------------

self.mplwidget = MplWidget(self)
self.mplwidget.pltCanv.setEnabled(False) # <- this doesn't work

to make it clear that there is nothing to interact with in this widget. Is there an easy workaround?

Answer 1

Grey out figure.

You may grey out the figure by placing a grey, semitransparent patch on top of it. To this end, you may create a Rectangle, set its zorder very high and give it the figure transform. To add it to a an axes, you may use ax.add_patch ; however in order to add it to a figure with a 3D axes, this will not work and you would need to add it via fig.patches.extend . (See this answer )

import matplotlib.pyplot as plt
from mpl_toolkits.mplot3d import Axes3D
fig = plt.figure()
ax = fig.add_subplot(111, projection='3d')
ax.plot([1,3,2],[1,2,3],[2,3,2])

rect=plt.Rectangle((0,0),1,1, transform=fig.transFigure, 
                   clip_on=False, zorder=100, alpha=0.5, color="grey")
fig.patches.extend([rect])

plt.show()

Disconnecting all events

You may disconnect all events from the canvas. This will prevent any user interaction, but is also not reversible; so if you need those events back at a later stage the solution would be more complicated.

import matplotlib.pyplot as plt
from mpl_toolkits.mplot3d import Axes3D
fig = plt.figure()
ax = fig.add_subplot(111, projection='3d')
ax.plot([1,3,2],[1,2,3],[2,3,2])

for evt, callback in fig.canvas.callbacks.callbacks.items():
    for cid, _ in callback.items():
        fig.canvas.mpl_disconnect(cid)
plt.show()