So, I was watching some videos about how to do the Guis with blocks mainly with Containers & Screens, once loading up my game, and click on my block, I noticed that the gui was shown for a split second until it crashed my game.
The video I was watching - https://www.youtube.com/watch?v=GsV_pKkE1mo&list=PLmaTwVFUUXiBKYYSyrv_uPPoPZtEsCBVJ&index=5&t=1692s
My Container Class -
https://sourceb.in/9568761a4b.java
My Screen Class -
https://sourceb.in/712ae79b4c.java
My error -