diff -r fbe4bb4eba8c -r 832e9288f8e2 ui/gtk/menu.c
--- a/ui/gtk/menu.c	Wed Dec 31 11:06:54 2025 +0100
+++ b/ui/gtk/menu.c	Wed Dec 31 11:36:42 2025 +0100
@@ -153,25 +153,32 @@
     GtkWidget *widget = gtk_check_menu_item_new_with_mnemonic(ci->label);
     gtk_menu_shell_append(GTK_MENU_SHELL(p), widget);
     
-    if(ci->callback) {
-        UiEventData *event = malloc(sizeof(UiEventData));
-        event->obj = obj;
-        event->userdata = ci->userdata;
-        event->callback = ci->callback;
-        event->value = 0;
-        event->customdata = NULL;
-        
-        g_signal_connect(
-                widget,
-                "toggled",
-                G_CALLBACK(ui_menu_event_toggled),
-                event);
-        g_signal_connect(
-                widget,
-                "destroy",
-                G_CALLBACK(ui_destroy_userdata),
-                event);
+    UiVarEventData *event = malloc(sizeof(UiVarEventData));
+    memset(event, 0, sizeof(UiVarEventData));
+    event->obj = obj;
+    event->userdata = ci->userdata;
+    event->callback = ci->callback;
+    event->var = uic_widget_var(obj->ctx, obj->ctx, NULL, ci->varname, UI_VAR_INTEGER);
+    if(event->var) {
+        UiInteger *v = event->var->value;
+        v->obj = widget;
+        v->get = ui_checkitem_get;
+        v->set = ui_checkitem_set;
+        if(v->value != 0) {
+            gtk_check_menu_item_set_active(GTK_CHECK_MENU_ITEM(widget), TRUE);
+        }
     }
+
+    g_signal_connect(
+            widget,
+            "toggled",
+            G_CALLBACK(ui_menu_event_toggled),
+            event);
+    g_signal_connect(
+            widget,
+            "destroy",
+            G_CALLBACK(ui_destroy_userdata),
+            event);
 }
 
 void add_radioitem_widget(GtkWidget *p, int index, UiMenuItemI *item, UiObject *obj) {
@@ -323,14 +330,23 @@
     uic_set_tmp_eventdata(NULL, 0);
 }
 
-void ui_menu_event_toggled(GtkCheckMenuItem *ci, UiEventData *event) {
+void ui_menu_event_toggled(GtkCheckMenuItem *ci, UiVarEventData *event) {
+    UiInteger *i = event->var ? event->var->value : NULL;
+    
     UiEvent evt;
     evt.obj = event->obj;
     evt.window = event->obj->window;
     evt.document = event->obj->ctx->document;
-    evt.eventdata = NULL;
+    evt.eventdata = i;
+    evt.eventdatatype = i ? UI_EVENT_DATA_INTEGER_VALUE : 0;
     evt.intval = gtk_check_menu_item_get_active(ci);
-    event->callback(&evt, event->userdata);    
+    if(event->callback) {
+        event->callback(&evt, event->userdata);
+    }
+    
+    if(i) {
+        ui_notify_evt(i->observers, &evt);
+    }
 }
 
 int64_t ui_checkitem_get(UiInteger *i) {
@@ -341,7 +357,7 @@
 
 void ui_checkitem_set(UiInteger *i, int64_t value) {
     i->value = value;
-    gtk_check_menu_item_set_active(i->obj, value);
+    gtk_check_menu_item_set_active(i->obj, (gboolean)value);
 }