Interactive matplotlib plot in PySimpleGUI - matplotlib

Question

I'm trying to get the RectangleSelector form matplotlib.widgets to work with PySimpleGUI.
I'm basing my test code on the RectangleSelector demo shown in the accepted answer on this question.
I'm getting the plot to show in PySimpleGUI but it's not interactive. Is it even possible in PySimpleGUI to have interactive matplotlib widgets?
import PySimpleGUI as sg
import numpy as np
import matplotlib.pyplot as plt
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg
from matplotlib.widgets import RectangleSelector
import matplotlib
matplotlib.use('TkAgg')
xdata = np.linspace(0,9*np.pi, num=301)
ydata = np.sin(xdata)
fig, ax = plt.subplots()
line, = ax.plot(xdata, ydata)
def draw_figure(canvas, figure):
figure_canvas_agg = FigureCanvasTkAgg(figure, canvas)
figure_canvas_agg.draw()
figure_canvas_agg.get_tk_widget().pack(side="top", fill="both", expand=1)
return figure_canvas_agg
def line_select_callback(eclick, erelease):
x1, y1 = eclick.xdata, eclick.ydata
x2, y2 = erelease.xdata, erelease.ydata
rect = plt.Rectangle( (min(x1,x2),min(y1,y2)), np.abs(x1-x2), np.abs(y1-y2) )
ax.add_patch(rect)
rs = RectangleSelector(ax, line_select_callback,
drawtype='box', useblit=False, button=[1],
minspanx=5, minspany=5, spancoords='pixels',
interactive=True)
layout = [[sg.Canvas(key="-CANVAS-")]]
window = sg.Window('test', layout, finalize=True, element_justification='center', font='Helvetica 16')
draw_figure(window["-CANVAS-"].TKCanvas, fig)
event, values = window.read()
Edit: Thanks to MikeyB for the pointer, I now have the following code, which shows an interactive plot, but it's still not possible to draw rectangles. The callback function doesn't seem to be firing. New code below:
import PySimpleGUI as sg
import numpy as np
from matplotlib.widgets import RectangleSelector
import matplotlib.figure as figure
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg, NavigationToolbar2Tk
# instantiate matplotlib figure
fig = figure.Figure()
ax = fig.add_subplot(111)
DPI = fig.get_dpi()
fig.set_size_inches(505 * 2 / float(DPI), 707 / float(DPI))
# ------------------------------- This is to include a matplotlib figure in a Tkinter canvas
def draw_figure_w_toolbar(canvas, fig, canvas_toolbar):
if canvas.children:
for child in canvas.winfo_children():
child.destroy()
if canvas_toolbar.children:
for child in canvas_toolbar.winfo_children():
child.destroy()
figure_canvas_agg = FigureCanvasTkAgg(fig, master=canvas)
figure_canvas_agg.draw()
toolbar = Toolbar(figure_canvas_agg, canvas_toolbar)
toolbar.update()
figure_canvas_agg.get_tk_widget().pack(side='right', fill='both', expand=1)
def line_select_callback(eclick, erelease):
x1, y1 = eclick.xdata, eclick.ydata
x2, y2 = erelease.xdata, erelease.ydata
rect = plt.Rectangle( (min(x1,x2),min(y1,y2)), np.abs(x1-x2), np.abs(y1-y2) )
print(rect)
ax.add_patch(rect)
class Toolbar(NavigationToolbar2Tk):
def __init__(self, *args, **kwargs):
super(Toolbar, self).__init__(*args, **kwargs)
# ------------------------------- PySimpleGUI CODE
layout = [
[sg.B('start', key='start')],
[sg.Canvas(key='controls_cv')],
[sg.Column(
layout=[
[sg.Canvas(key='fig_cv',
# it's important that you set this size
size=(500 * 2, 700)
)]
],
background_color='#DAE0E6',
pad=(0, 0)
)],
]
window = sg.Window('Test', layout)
while True:
event, values = window.read()
print(event, values)
if event == sg.WIN_CLOSED:
break
elif event == 'start':
x = np.linspace(0, 2 * np.pi)
y = np.sin(x)
line, = ax.plot(x, y)
rs = RectangleSelector(ax, line_select_callback,
drawtype='box', useblit=False, button=[1],
minspanx=5, minspany=5, spancoords='pixels',
interactive=True)
draw_figure_w_toolbar(window['fig_cv'].TKCanvas, fig, window['controls_cv'].TKCanvas)
window.close()

Answer 1

Is it even possible in PySimpleGUI to have interactive matplotlib widgets?
Yes.
The demo program on the project's GitHub shows how to make an interactive Matplotlib drawing.
https://github.com/PySimpleGUI/PySimpleGUI/blob/master/DemoPrograms/Demo_Matplotlib_Embedded_Toolbar.py
You need to embed the controls into the window.

Answer 2

you need to add
fig.canvas.draw()
to your callback-function if you want the plot to be updated after the callback has triggered!
here's an updated version of your code that works just fine:
import PySimpleGUI as sg
import numpy as np
from matplotlib.widgets import RectangleSelector
import matplotlib.figure as figure
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg, NavigationToolbar2Tk
import matplotlib.pyplot as plt
# instantiate matplotlib figure
fig = figure.Figure()
ax = fig.add_subplot(111)
DPI = fig.get_dpi()
fig.set_size_inches(505 * 2 / float(DPI), 707 / float(DPI))
# ------------------------------- This is to include a matplotlib figure in a Tkinter canvas
def draw_figure_w_toolbar(canvas, fig, canvas_toolbar):
if canvas.children:
for child in canvas.winfo_children():
child.destroy()
if canvas_toolbar.children:
for child in canvas_toolbar.winfo_children():
child.destroy()
figure_canvas_agg = FigureCanvasTkAgg(fig, master=canvas)
figure_canvas_agg.draw()
toolbar = Toolbar(figure_canvas_agg, canvas_toolbar)
toolbar.update()
figure_canvas_agg.get_tk_widget().pack(side='right', fill='both', expand=1)
def line_select_callback(eclick, erelease):
x1, y1 = eclick.xdata, eclick.ydata
x2, y2 = erelease.xdata, erelease.ydata
rect = plt.Rectangle( (min(x1,x2),min(y1,y2)), np.abs(x1-x2), np.abs(y1-y2) )
print(rect)
ax.add_patch(rect)
fig.canvas.draw()
class Toolbar(NavigationToolbar2Tk):
def __init__(self, *args, **kwargs):
super(Toolbar, self).__init__(*args, **kwargs)
# ------------------------------- PySimpleGUI CODE
layout = [
[sg.B('start', key='start')],
[sg.Canvas(key='controls_cv')],
[sg.Column(
layout=[
[sg.Canvas(key='fig_cv',
# it's important that you set this size
size=(500 * 2, 700)
)]
],
background_color='#DAE0E6',
pad=(0, 0)
)],
]
window = sg.Window('Test', layout)
while True:
event, values = window.read()
print(event, values)
if event == sg.WIN_CLOSED:
break
elif event == 'start':
x = np.linspace(0, 2 * np.pi)
y = np.sin(x)
line, = ax.plot(x, y)
rs = RectangleSelector(ax, line_select_callback,
drawtype='box', useblit=False, button=[1],
minspanx=5, minspany=5, spancoords='pixels',
interactive=True)
draw_figure_w_toolbar(window['fig_cv'].TKCanvas, fig, window['controls_cv'].TKCanvas)
window.close()