How to merge uitrees?

I have a Model in simulink with various Subsystems. when i click on one of These Subsystems a Gui opens and Shows two uitrees. On the left uitree are all available ports in every Subsystem given. Now i want to be able to choose specific ports and put them on the right uitree in the same order like the left uitree. I only Need help with uitree because i don't get how to merge the uitrees with Java or Matlab functions