Draw issues with jupyter lab and %matplotlib widget (#129)

* Draw issues with jupyter lab and %matplotlib widget

* Changelog

Author: nabobalis

changelog/129.bugfix.rst

@@ -0,0 +1 @@
+Switched the backend to use ``draw_idle`` to avoid Jupyter lab widget issues.

mpl_animators/base.py

@@ -257,12 +257,12 @@ def _set_active_slider(self, ind):
     def _highlight_slider(self, ind):
         ax = self.sliders[ind]
         [a.set_linewidth(2.0) for n, a in ax.spines.items()]
-        self.fig.canvas.draw()
+        self.fig.canvas.draw_idle()
 
     def _dehighlight_slider(self, ind):
         ax = self.sliders[ind]
         [a.set_linewidth(1.0) for n, a in ax.spines.items()]
-        self.fig.canvas.draw()
+        self.fig.canvas.draw_idle()
 
 # =============================================================================
 #   Build the figure and place the widgets