Reload method inside TAB

Hi everyone i need to reload a method inside a tab…
I have a catalog that store an item inside a SQLite and update te badge untill there all its ok.
When i change to the tab cart i show a list with the stored items but no add the last one. If i restart the app its appears.
I try with onSelected() method but works only if i tab twise the cart.
I dont have ideas 2 weeks searching… and nothing…
Any help.