--- a/ui/common/wrapper.c	Tue May 19 18:31:16 2026 +0200
+++ b/ui/common/wrapper.c	Tue May 19 18:32:34 2026 +0200
@@ -45,6 +45,11 @@
     obj->window = windowdata;
 }
 
+void ui_object_set_onclose(UiObject *obj, ui_callback callback, void *userdata) {
+    obj->onclose = callback;
+    obj->onclosedata = userdata;
+}
+
 
 /* ---------------------------- UiList ---------------------------- */