Add func TreeViewHelper.get_popup_rectangle

src/gpodder/gtkui/interface/common.py

@@ -382,6 +382,36 @@ class TreeViewHelper(object):
         treeview.set_cursor(path)
         return True
 
+    @staticmethod
+    def get_popup_rectangle(treeview, event, column=0):
+        """
+        :return: Gdk.Rectangle to pass to Gtk.Popover.set_pointing_to()
+
+        If event is given, return a zero-width and height rectangle with the
+        event coordinates. If event is None, get the area of the column in the
+        first selected treeview row.
+
+        Used for instance when the popup trigger is the Menu key: It will
+        position the popover on top of the column on the selected row, even if
+        the mouse is elsewhere
+        """
+        if event is not None:
+            area = Gdk.Rectangle()
+            area.x, area.y = treeview.convert_bin_window_to_widget_coords(event.x, event.y)
+            return area
+
+        # If there's a selection, place the popup menu on top of
+        # the first-selected row and given column (otherwise in the top left corner)
+        selection = treeview.get_selection()
+        model, paths = selection.get_selected_rows()
+        if paths:
+            path = paths[0]
+            area = treeview.get_cell_area(path, treeview.get_column(column))
+        else:
+            area = Gdk.Rectangle()  # x, y, width, height are all 0
+
+        area.x, area.y = treeview.convert_bin_window_to_widget_coords(area.x, area.y)
+
 
 class ExtensionMenuHelper(object):
     """A helper class to handle extension submenus"""