I am attempting to build a Header component with a Tablist on it and i created 3 custom properties:
TablistItems: an input data table provide the name of the screens;
DefaultSelectedItems: an input data record provides the default selected screen;
OnSelect: event to control the clicking;
App.OnStart : define a table as the screens list for the current APP:
Set (gblPageList, ["S1", "S2", "S3" ]);
save the app and restart to make sure the variable declared.
I d like to use this variable for tablistItems, and the 1st record of it on DefaultSelectedItems -- which worked when i use the tablist outside of a component. ( one screen only but several containers visible or not according to the selected item in a tablist, it worked with a bad performance) -- but failed on both:

both of the custom properties show the same error:


I tried another way on building the header component by adding buttons for page navigation but the count of the buttons could be different among APPs, i am wondering if tablist could help with the dynamic page switching function.