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Thanks, copeg. I will check out the reading and go from there. :)

I hope this is an SSCCE. I think you should be able to run this and recreate my results. Thanx again for any help. :)


import acm.program.*;
import java.awt.event.*;
import javax.swing.*;
...

Pardon my newbie-ness... what's an SSCCE? Also, is there a different way to add the ActionListener to the JTextField specifically? I thought I had already added it properly as demonstrated in the 1st...

Thanks, copeg. But when I run the program, I do click in the JTextField, type a string, and then hit ENTER. Nothing happens. When I hit the JButton that has the same CommandAction, then the event...

Hello, all. I have the following code in my init() method:


friend = new JTextField(TEXT_FIELD_SIZE);
friend.setActionCommand("Add Friend");
add(friend, WEST);
add(new JButton("Add...

Thank you, pbrockway2, for the additional instruction. I'm really enjoying learning the language and the lingo of the programming world. Thanks for your patience and your help! :cool:

Okay... so I finally answered my own question. Just for reference, I had forgotten to instantiate the ArrayList in my ivars at the bottom of the program. Instead of...

ArrayList<String> friends =...

Okay, so actually your comments were really helpful once I started digging. The original problem was the line:


friends.clear();

because there weren't any entries in the ArrayList<String>...

Still learning terminology... Is this the stack trace to which you are referring:


Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at...

Hi. I'm learning java through Standford's Open Courseware, and while it's a phenomenal program, and I've been able to work each of the assignments on my own thus far without the teacher contact that...