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+From federico on IRC:
+
+GtkLabel just does two things for accessibility:
+
+1. Set its role on the GTK side to GTK_ACCESSIBLE_ROLE_LABEL in the class initialization function gtk_label_class_init ([[https://gitlab.gnome.org/GNOME/gtk/-/blob/8944493e/gtk/gtklabel.c#L2675]])
+
+  Later, that gets translated with gtk_accessible_role_to_atspi_role() to an AtspiRole enum value in gtk_accessible_role_to_atspi_role ([[https://gitlab.gnome.org/GNOME/gtk/-/blob/8944493e/gtk/a11y/gtkatspiutils.c#L38]])
+
+  Those enum values in AtspiRole ([[https://gitlab.gnome.org/GNOME/gtk/-/blob/8944493e/gtk/a11y/gtkatspiprivate.h#L27-158]]) correspond to the integer values that the Accessible.GetRole() method expects ([[https://gitlab.gnome.org/GNOME/gtk/-/blob/8944493e/gtk/a11y/atspi/Accessible.xml#L40]]), and which are unfortunately just hardcoded in atspi-constants.h ([[https://gitlab.gnome.org/GNOME/at-spi2-core/-/blob/master/atspi/atspi-constants.h]])
+
+2. The other thing GtkLabel does is to change its text in its corresponding GtkAtContext. Every widget gets a GtkAtContext created for it; it's just an object that collects data to feed to the a11y backend.  gtk_label_set_text_internal ([[https://gitlab.gnome.org/GNOME/gtk/-/blob/8944493e/gtk/gtklabel.c#L3010-3012]]) is where the label changes the text, and much later that gets collected, and sent to the accessibility backend's state_change method , gtk_at_context_update ([[https://gitlab.gnome.org/GNOME/gtk/-/blob/8944493e/gtk/gtkatcontext.c#L693-695]])
+
+  The only implementation of state_change right now is for the atspi backend.  And for labels in particular, gtk_at_spi_context_state_change ([[https://gitlab.gnome.org/GNOME/gtk/-/blob/8944493e/gtk/a11y/gtkatspicontext.c#L1084-1089]]) picks up the new accessible-name, and emits it as a dbus signal via emit_property_changed() in emit_property_changed ([[https://gitlab.gnome.org/GNOME/gtk/-/blob/8944493e/gtk/a11y/gtkatspicontext.c#L803-819]])
+
+Going in the other direction, when a screen reader asks an accessible object for its Name property:
+
+The gtkatspicontext receives the property request from dbus, and processes it in handle_accessible_get_property ([[https://gitlab.gnome.org/GNOME/gtk/-/blob/8944493e/gtk/a11y/gtkatspicontext.c#L671-676]]) - that calls gtk_at_context_get_name(), which is at [[https://gitlab.gnome.org/GNOME/gtk/-/blob/8944493e/gtk/gtkatcontext.c#L1091]] and the first thing that function does is to call gtk_at_context_get_name_accumulate(), which does the ARIA magic to compute a name based on an object's actual label, labelled-by, etc.  ([[https://gitlab.gnome.org/GNOME/gtk/-/blob/8944493e/gtk/gtkatcontext.c#L929-934])]
+
+How editable_handle_method() gets called?  GTK uses the g_dbus API internally to talk DBus.  Whereas in python it's super easy to do something like
+
+    @dbus.service.method('org.my.Interface.Name', in_signature="whatever", out_signature="whatever")
+    def MyMethodName(self, blah, blah, blah):
+
+In C it's a bit more complicated.  g_dbus wants to be told the path of the object, the name of an interface, and a vtable with functions that when called, can deal with calling methods or getting/setting properties
+
+For example, [[https://gitlab.gnome.org/GNOME/gtk/-/blob/8944493e/gtk/a11y/gtkatspicontext.c#L1341-1354]] first gets the vtable for the editable text interface, and calls g_dbus_connection_register_object().  That vtable is gtk_at_spi_context_register_object ([[https://gitlab.gnome.org/GNOME/gtk/-/blob/8944493e/gtk/a11y/gtkatspieditabletext.c#L341-344]]) - its first element is the handler that g_dbus will call when it wants to call a method on the interface.  The "call a method
+
+From the editable text interface" handler is text_view_handle_method ([[https://gitlab.gnome.org/GNOME/gtk/-/blob/8944493e/gtk/a11y/gtkatspieditabletext.c#L209]]) - you'll see that it compares the method_name with SetTextContents,  InsertText, etc. - all methods names from [[https://gitlab.gnome.org/GNOME/at-spi2-core/-/blob/master/xml/EditableText.xml]]