ModalNavigationDrawer: add possibility to react on selection changes of group and item simultaneously (slint-ui#10008)

* ModalNavigationDrawer: add possibility to react on selection changes of group and item simultaneously like in NavigationDrawer

* Add arguments and their description to the documentation

* align style

Author: Murmele

ui-libraries/material/docs/src/content/docs/components/Navigation/modal_navigation_drawer.mdx

@@ -64,8 +64,8 @@ Selects the navigation item at the specified group and item indices.
 
 ## Callbacks
 
-### selected()
-Invoked when an item is selected
+### selected(group-index: int, item-index: int)
+Invoked when an item is selected. `group-index` is the index of the selected group and `item-index` the selected index in that group.
 
 ### item_pointer_event()
 Emitted on any mouse pointer event similar to `TouchArea`. Arguments are the group and item index associated with the event, the `PointerEvent` itself and the mouse position within the `NavigationDrawer`.

ui-libraries/material/docs/src/content/docs/components/Navigation/navigation_drawer.mdx

@@ -57,8 +57,8 @@ Selects the navigation item at the specified group and item indices.
 
 ## Callbacks
 
-### selected()
-Invoked when an item is selected
+### selected(group-index: int, item-index: int)
+Invoked when an item is selected. `group-index` is the index of the selected group and `item-index` the selected index in that group.
 
 ### item_pointer_event()
 Emitted on any mouse pointer event similar to `TouchArea`. Arguments are the group and item index associated with the event, the `PointerEvent` itself and the mouse position within the `NavigationDrawer`.

ui-libraries/material/src/ui/components/navigation_drawer.slint

@@ -142,7 +142,7 @@ component NavigationGroupTemplate {
 }
 
 export component NavigationDrawer inherits Drawer {
-    callback selected(group-index: int, item_index: int);
+    callback selected(group-index: int, item-index: int);
     callback item_pointer_event(group_index: int, item_index: int, event: PointerEvent, position: Point);
     in property <[NavigationGroup]> groups;
     in_out property <int> current_group;
@@ -179,6 +179,7 @@ export component NavigationDrawer inherits Drawer {
 }
 
 export component ModalNavigationDrawer inherits ModalDrawer {
+    callback selected(group-index: int, item-index: int);
     in property <[NavigationGroup]> groups;
     in_out property <int> current_group;
     in_out property <int> current_index;
@@ -207,5 +208,6 @@ export component ModalNavigationDrawer inherits ModalDrawer {
         root.current_group = group_index;
         root.current_index = item_index;
         root.close();
+        root.selected(group_index, item_index);
     }
 }