Merge pull request matplotlib#21478 from QuLogic/gtk4-embedding

Fix GTK4 embedding example

Author: jklymak

lib/matplotlib/backends/_backend_gtk.py

@@ -43,7 +43,7 @@ def _create_application():
 
     if _application is None:
         app = Gio.Application.get_default()
-        if app is None or getattr(app, '_created_by_matplotlib'):
+        if app is None or getattr(app, '_created_by_matplotlib', False):
             # display_is_valid returns False only if on Linux and neither X11
             # nor Wayland display can be opened.
             if not mpl._c_internal_utils.display_is_valid():

lib/matplotlib/backends/backend_gtk3agg.py

@@ -70,8 +70,10 @@ def blit(self, bbox=None):
         self.queue_draw_area(x, y, width, height)
 
     def draw(self):
+        # Call these explicitly because GTK's draw is a GObject method which
+        # isn't cooperative with Python class methods.
         backend_agg.FigureCanvasAgg.draw(self)
-        super().draw()
+        backend_gtk3.FigureCanvasGTK3.draw(self)
 
 
 class FigureManagerGTK3Agg(backend_gtk3.FigureManagerGTK3):

lib/matplotlib/backends/backend_gtk4agg.py

@@ -27,7 +27,7 @@ def on_draw_event(self, widget, ctx):
         ctx = backend_cairo._to_context(ctx)
 
         buf = cbook._unmultiplied_rgba8888_to_premultiplied_argb32(
-            np.asarray(self.renderer.buffer_rgba()))
+            np.asarray(self.get_renderer().buffer_rgba()))
         height, width, _ = buf.shape
         image = cairo.ImageSurface.create_for_data(
             buf.ravel().data, cairo.FORMAT_ARGB32, width, height)
@@ -38,8 +38,10 @@ def on_draw_event(self, widget, ctx):
         return False
 
     def draw(self):
+        # Call these explicitly because GTK's draw is a GObject method which
+        # isn't cooperative with Python class methods.
         backend_agg.FigureCanvasAgg.draw(self)
-        super().draw()
+        backend_gtk4.FigureCanvasGTK4.draw(self)
 
 
 class FigureManagerGTK4Agg(backend_gtk4.FigureManagerGTK4):