Fix the windows backend

Author: playmer

examples/video/01-menubar/menubar.c

@@ -43,7 +43,7 @@ void CreateMenuBar()
   {
     SDL_MenuItem* menu = SDL_CreateMenuItem(bar, "File", SDL_MENU, MENU_BAR_LAST);
     new_window = SDL_CreateMenuItem(menu, "New Window", SDL_MENU_BUTTON, MENU_BAR_FILE_NEW_WINDOW);
-    checkable = SDL_CreateMenuItem(menu, "Autosave Tabs on Close", SDL_MENU_CHECKABLE, MENU_BAR_FILE_DISABLE_NEW_WINDOW);
+    checkable = SDL_CreateMenuItem(menu, "Enable New Window", SDL_MENU_CHECKABLE, MENU_BAR_FILE_DISABLE_NEW_WINDOW);
 
     SDL_CheckMenuItem(checkable);
   }

src/video/SDL_video.c

@@ -6093,21 +6093,26 @@ SDL_MenuItem *SDL_CreateMenuItemAt(SDL_MenuItem *menu_bar_as_item, size_t index,
 
     // Get the last item in the list and insert our new item.
     if (menu->child_list) {
-        SDL_MenuItem *current = menu->child_list;
+        if (index == 0) {
+            menu_item->common.next = menu->child_list;
+            menu->child_list->common.prev = menu_item;
+            menu->child_list = menu_item;
+        } else {
+            SDL_MenuItem *current = menu->child_list;
+            for (size_t i = 1; (i < index) && current; ++i) {
+                current = current->common.next;
+            }
 
-        for (size_t i = 1; (i < index) && current; ++i) {
-            current = current->common.next;
-        }
+            SDL_assert(current);
 
-        SDL_assert(current);
+            if (current->common.next) {
+                current->common.next->common.prev = menu_item;
+                menu_item->common.next = current->common.next;
+            }
 
-        if (current->common.next) {
-            current->common.next->common.prev = menu_item;
-            menu_item->common.next = current->common.next;
+            current->common.next = menu_item;
+            menu_item->common.prev = current;
         }
-
-        current->common.next = menu_item;
-        menu_item->common.prev = current;
     } else {
         menu->child_list = menu_item;
     }
@@ -6241,7 +6246,7 @@ bool SDL_DestroyMenuItem(SDL_MenuItem *menu_item)
 
     if (menu_item->common.prev) {
         menu_item->common.prev->common.next = menu_item->common.next;
-        menu_item->common.next->common.next = menu_item->common.prev;
+        menu_item->common.next->common.prev = menu_item->common.prev;
 
         if (menu_item == menu_item->common.parent->menu_common.child_list) {
             menu_item->common.parent->menu_common.child_list = menu_item->common.next;

src/video/windows/SDL_windowsvideo.c

@@ -945,7 +945,7 @@ static bool Win32_MenuItemEnabled(SDL_MenuItem *menu_item, bool *enabled)
         return WIN_SetError("Unable to get menu_item check state.");
     }
 
-    *enabled = !(flags & MF_DISABLED);
+    *enabled = !(flags & MF_GRAYED);
 
     return true;
 }
@@ -984,7 +984,7 @@ static bool Win32_DestroyMenuItem(SDL_MenuItem *menu_item)
             return WIN_SetError("Unable to remove menu item.");
         }
     } else {
-        DeleteMenu((HMENU)platform_data->self_handle, i, MF_BYPOSITION);
+        DeleteMenu((HMENU)platform_data->owner_handle, i, MF_BYPOSITION);
     }
 
     SDL_free(menu_item->common.platform_data);