Custom admin menu creation - parent_id and level values are resetting to zero

Question

I want to programmatically create some admin menu items for my component and I'm most of the way there, but I can't seem to set the hierarchy for them. I am wanting three menu items - one as the parent menu item which expands to reveal two submenu items beneath it.

I am setting all of my values for each menu item in an instance of Joomla\CMS\Table\Menu ($menu) and then calling $menu->check() followed by $menu->store().

For my parent item I am setting parent_id to 1 and level to 1. When I use $menu->store() to create it, I get the new ID that has been assigned to it and use that as the parent_id for the 2 sub-menu items. I also set the level for each of them to 2. Unfortunately the repositioning function that works out the lft and rgt menu items is resetting the parent_id and level values to zero for all three of my menu items, so I'm ending up with them all on the same level.

Any idea how I can get my values to persist? Or do I need to rethink how I'm doing this?

Answer 1

I ended up addressing this by not setting the parent_id and level values when I initially created the menu items with menu->store(). Instead, once that process had completed and it passed me back the id for the new menu item, that enabled me to construct a database update so I could manually update those two values that way instead.

Not quite the nice neat way I was hoping for but it's got the job done.

Answer 2

In my Joomla 4 component I use the following:

        $menuTable = JTable::getInstance('menu', 'JTable');
        $menuTable->setLocation($id, 'last-child');

        if (!$menuTable->save($menuItem))
        {
            throw new Exception($menuTable->getError());
        }

And especially the setLocation 'last-child' part is what did the trick for me.

From docs.joomla:

However, in order to determine where in the tree the new node is to be inserted, you need to make a call to the setLocation method. The setLocation method takes two arguments. The first is the id of a "reference" node in the tree. The new node will be inserted relative to this node with the relationship being specified by the second argument. Possible values for this relationship are:

before - the new node will be inserted before the reference node but at the same level.

after - the new node will be inserted after the reference node but at the same level.

first-child - the new node will be inserted as the first child node of the reference node.

last-child - the new node will be inserted as the last child node of the reference node.

Specify where to insert the new node. $table->setLocation($reference_id, 'first-child');

-- edit --

I don't really know if this is still best practice for Joomla 4 and above as I find it hard to get updated information on the matter. Please share you knowledge.