Sets the name of an icon to show inside the menu button.
Setting icon name resets gtk.menu_button.MenuButton.label and gtk.menu_button.MenuButton.child.
If propertyGtk.MenuButton:always-show-arrow is set to TRUE and gtk.menu_button.MenuButton.direction is not gtk.types.ArrowType.None, a dropdown arrow will be shown next to the icon.
the icon name
Sets the name of an icon to show inside the menu button.
Setting icon name resets gtk.menu_button.MenuButton.label and gtk.menu_button.MenuButton.child.
If propertyGtk.MenuButton:always-show-arrow is set to TRUE and gtk.menu_button.MenuButton.direction is not gtk.types.ArrowType.None, a dropdown arrow will be shown next to the icon.