Demo Matplotlib, Canvas Element changes, new Frame Element, added pad to Text, Slider

Plus a few other tweaks & bug fixes

Demo_Matplotlib.py

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+import PySimpleGUI as g
+import matplotlib
+matplotlib.use('TkAgg')
+from numpy import arange, sin, pi
+from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg, FigureCanvasAgg
+from matplotlib.figure import Figure
+import matplotlib.backends.tkagg as tkagg
+import sys
+import tkinter as Tk
+
+"""
+Demonstrates one way of embedding Matplotlib figures into a PySimpleGUI window.
+
+Basic steps are:
+ * Create a Canvas Element
+ * Layout form
+ * Display form (NON BLOCKING)
+ * Draw plots onto convas
+ * Display form (BLOCKING)
+"""
+
+
+def draw_figure(canvas, figure, loc=(0, 0)):
+    """ Draw a matplotlib figure onto a Tk canvas
+
+    loc: location of top-left corner of figure on canvas in pixels.
+
+    Inspired by matplotlib source: lib/matplotlib/backends/backend_tkagg.py
+    """
+    figure_canvas_agg = FigureCanvasAgg(figure)
+    figure_canvas_agg.draw()
+    figure_x, figure_y, figure_w, figure_h = figure.bbox.bounds
+    figure_w, figure_h = int(figure_w), int(figure_h)
+    photo = Tk.PhotoImage(master=canvas, width=figure_w, height=figure_h)
+
+    # Position: convert from top-left anchor to center anchor
+    canvas.create_image(loc[0] + figure_w/2, loc[1] + figure_h/2, image=photo)
+
+    # Unfortunately, there's no accessor for the pointer to the native renderer
+    tkagg.blit(photo, figure_canvas_agg.get_renderer()._renderer, colormode=2)
+
+    # Return a handle which contains a reference to the photo object
+    # which must be kept live or else the picture disappears
+    return photo
+
+f = Figure(figsize=(5, 4), dpi=100)
+a = f.add_subplot(111)
+t = arange(0.0, 3.0, 0.01)
+s = sin(2*pi*t)
+
+a.plot(t, s)
+a.set_title('Tk embedding')
+a.set_xlabel('X axis label')
+a.set_ylabel('Y label')
+
+# -------------------------------- GUI Starts Here --------------------------------
+canvas_elem = g.Canvas(size=(500, 400))         # get the canvas we'll be drawing on
+# define the form layout
+layout = [[g.Text('Plot test')],
+          [canvas_elem],
+          [g.OK(pad=((250,0), 3))]]
+
+# create the form and show it without the plot
+form = g.FlexForm('Demo Application - Embedding Matplotlib In PySimpleGUI')
+form.Layout(layout)
+form.ReadNonBlocking()
+
+# add the plot to the window
+fig_photo = draw_figure(canvas_elem.TKCanvas, f)
+
+# show it all again and get buttons
+button, values = form.Read()
+