The code is kind of long for a forum, where people expect the user to present a short, clear example of a question, and difficult to read because of the lack of indentions. It's no wonder you haven't gotten any help yet.
Do you know how to read the error messages? Your first says that on line 106, the method gui.setVisible() could not be found.
Since gui is a "TrepForm" we have to look there to see if the method has been created with this name and "signature"(refers to the arguments or lack thereof). Indeed, there are no such methods, but JPanel (the Object that is extended by TrepForm) does have setVisible(boolean), albeit by itself extending JComponent. So, I'm guessing probably you need to add a boolean as an argument.
Java considers setVisible() and setVisible(boolean) to be two distinct methods.
If you continue to have trouble figuring out the other error messages, you will have a better chance of getting help if you try to isolate a smaller example that illustrates the question, and present that.