how to add user vhdl files into quartus top level entity

[Altera_Forum]

how to add user vhdl entities into quartus top level entity? 

I created the main entity from the pin planner with some megafuntions  and now I want to add my own entities into it ' I know how to write them into the file quartus created ' but whenever I will update my top entity ' the entity I created will be erased .  thanks///

[Altera_Forum]

Hi, 

 Updating your top level entity from pin planner will erase all your modifications you have made in this. Obviously.  In your top level entity, you may instantiate your other entities with port mapping. In quartus, Menu Project->Add/Remove files... Don't update your top level entity from pin planner.  ...  And compile...  ...