dynamic channel cover icon based on tree text size

See #590

src/gpodder/gtkui/draw.py

@@ -302,6 +302,7 @@ def cake_size_from_widget(widget=None):
     layout = Pango.Layout(pango_context)
     layout.set_font_description(font_desc)
     layout.set_text("1", -1)
+    # use text height as size
     return layout.get_pixel_size()[1]
 
 

src/gpodder/gtkui/main.py

@@ -77,8 +77,6 @@ N_ = gpodder.ngettext
 
 
 class gPodder(BuilderWidget, dbus.service.Object):
-    # Width (in pixels) of episode list icon
-    EPISODE_LIST_ICON_WIDTH = 40
 
     def __init__(self, app, bus_name, gpodder_core, options):
         dbus.service.Object.__init__(self, object_path=gpodder.dbus_gui_object_path, bus_name=bus_name)
@@ -734,10 +732,12 @@ class gPodder(BuilderWidget, dbus.service.Object):
         self.entry_search_podcasts.set_position(-1)
 
     def init_podcast_list_treeview(self):
+        size = cake_size_from_widget(self.treeChannels) * 2
+        self.podcast_list_model.set_max_image_size(size)
         # Set up podcast channel tree view widget
         column = Gtk.TreeViewColumn('')
         iconcell = Gtk.CellRendererPixbuf()
-        iconcell.set_property('width', 45)
+        iconcell.set_property('width', size + 10)
         column.pack_start(iconcell, False)
         column.add_attribute(iconcell, 'pixbuf', PodcastListModel.C_COVER)
         column.add_attribute(iconcell, 'visible', PodcastListModel.C_COVER_VISIBLE)

src/gpodder/gtkui/model.py

@@ -598,6 +598,10 @@ class PodcastListModel(Gtk.ListStore):
     def _show_row_separator(self, model, iter):
         return model.get_value(iter, self.C_SEPARATOR)
 
+    def set_max_image_size(self, size):
+        self._max_image_side = size
+        self._cover_cache = {}
+
     def _resize_pixbuf_keep_ratio(self, url, pixbuf):
         """
         Resizes a GTK Pixbuf but keeps its aspect ratio.
@@ -663,7 +667,10 @@ class PodcastListModel(Gtk.ListStore):
             loader = GdkPixbuf.PixbufLoader()
             loader.write(channel.cover_thumb)
             loader.close()
-            return loader.get_pixbuf()
+            pixbuf = loader.get_pixbuf()
+            if self._max_image_side not in (pixbuf.get_width(), pixbuf.get_height()):
+                logger.debug("cached thumb wrong size: %r != %i", (pixbuf.get_width(), pixbuf.get_height()), self._max_image_side)
+                return None
         except Exception as e:
             logger.warn('Could not load cached cover art for %s', channel.url, exc_info=True)
             channel.cover_thumb = None