Displaying to output widget from button click callback throws exception

Here’s a minimal example:

%matplotlib inline

from IPython.html import widgets
from IPython.display import display

def click(b):
    with out:
        print 'Hello world'

out=widgets.Output()
button=widgets.Button(description='Click Me')
button.on_click(click)
display(out)
display(button)

Executing a notebook cell with this code and clicking the button results in the following exception being thrown:

NameError: global name 'get_ipython' is not defined

This is with the Anaconda ipython / ipython-notebook version 3.2.1 packages on Windows.

This issue can be resolved by adding

from IPython import get_ipython

to IPython/html/widgets/widget_output.py, but I’m not familiar enough with the code to be sure if this is the correct place to make that change, or if the fix should be further upstream.

[kh90909]

Also, here’s a more functional example of updating an output widget from a button click callback, to show how this can be used to position output (e.g. a matplotlib plot) relative to other widgets:

%matplotlib inline

# To prevent automatic figure display when execution of the cell ends
%config InlineBackend.close_figures=False 

import matplotlib.pyplot as plt
import numpy as np

from IPython.html import widgets
from IPython.display import display,clear_output

plt.ioff()
ax=plt.gca()
plt.plot(np.random.randn(100),np.random.randn(100),'+')

out=widgets.Output()
button=widgets.Button(description='Next')
vbox=widgets.VBox(children=(out,button))
display(vbox)

def click(b):
    ax.lines[0].set_xdata(np.random.randn(100))
    ax.lines[0].set_ydata(np.random.randn(100))
    with out:
        clear_output(wait=True)
        display(ax.figure)

button.on_click(click)
click(None)

[jdfreder]

Thanks for clarifying @minrk