Hello, I have add AtkSocket/AtkPlug support to mate-panel here:
https://salsa.debian.org/hypra-team/mate-panel/blob/stretch-applets/debian/patches/1001_atk-socket-plug I am however wondering whether the complexity is needed and/or whether some of it could already be implemented in gtk. What I had to do is: * on the socket side: - create PanelSocket, a subclass of GtkSocket that creates an AtkSocket (actually a PanelAtkSocket, see below) and makes itself its accessible parent. - create PanelSocketAccessible, the corresponding subclass of GetContainerAccessible that overrides get_n_children and ref_child to return the AtkSocket as child of the accessible of the PanelSocket. - create PanelAtkSocket, a subclass of AtkSocket that makes its get_extents method call the parent's get_extents method. * on the plug side: - create PanelAPlug, a subclass of GtkPlug that creates an AtkPlug (actually a PanelAtkPlug, see below) and set it as accessible parent. - create PanelAtkPlug, a subclass of AtkPlug that makes it parent of the root of the applet, and calls ref_state_set from the root of the applet to implement the ref_state_set method. All of this is not specific to mate-panel so might be done by gtk itself, and the complexity seems useless: normally AtkSocket should directly be the accessible of GtkSocket, and ditto for AtkPlug/GtkPlug. But AFAICT: - To make AtkSocket the accessible of GtkSocket one would make GtkSocket call gtk_widget_class_set_accessible_type(GTK_TYPE_SOCKET_ACCESSIBLE). - But gtk_widget_class_set_accessible_type checks that GTK_TYPE_SOCKET_ACCESSIBLE is "a subtype of the type used for accessibles of the parent class". - Since the parent class of GtkSocket is GtkContainer, GtkSocketAccessible would have to be a parent of GtkContainerAccessible, and eventually of GtkAccessible. - But GtkAccessible contains an AtkObject, while AtkSocket extends AtkObject (to store the plug id). - Put another way, we'd want multi-heritage for GtkSocketAccessible: both GtkContainerAccessible and AtkSocket ; and AFAIK this is not supported by gobject (which makes sense: the AtkObject structure within GtkAccessible can't magically be extended to contain embedded_plug_id). ditto for AtkPlug/GtkPlug. Maybe another way would be to make GtkSocket/GtkPlug directly create AtkSocket/AtkPlug, and override the get_accessible method to return the AtkSocket/AtkPlug directly? I didn't see such approach used in gtk so I'm unsure if that's supposed to work? Or perhaps there might be possibly only a couple of bugs to fix to get it to work? Samuel _______________________________________________ gnome-accessibility-list mailing list gnome-accessibility-list@gnome.org https://mail.gnome.org/mailman/listinfo/gnome-accessibility-list
