java

[spunkie munkie]

when trying to compile i keep getting errors saying listlistener and buttonlistener aren't abstract. and i dont have a clue how to fix it as ive not played with java much before and never come across this erroe before

[Nodrog]

If your class is inheriting from an abstract class, you have to override all the methods declared abstract in the parent class before you can instantiate it.

[SYMM]

I'm curious as to why you're evening using ButtonListeners and ListListeners if you've never used Java before (as an aside, check your capitalisation- and if you want to listen for clicks of a button, its an ActionListener you need....), but otherwse what nodrog said

[Luckeh!!!!]

Originally Posted by spunkie munkie

when trying to compile i keep getting errors saying listlistener and buttonlistener aren't abstract. and i dont have a clue how to fix it as ive not played with java much before and never come across this erroe before

you need to start reading books, sound like you're jumping into the deep end

[spunkie munkie]

yeah well i should of probably payed more attention in lectures and the books i have arnt much use

[Weeks]

Well it's either that:
a) you've overidden methods you weren't suppose to.
b) you hadn't overridden some methods you were suppose too.

[wu_trax]

search for 'thinking in java' by Bruce Eckel. its a pdf-book and i pretty much liked it, covers all the important basics of java.

[spunkie munkie]

that book a help
but it still hasn't given me a clue as to go about makeing the listeners abstract

[Nodrog]

Originally Posted by spunkie munkie

that book a help
but it still hasn't given me a clue as to go about makeing the listeners abstract

Any class containing an abstract method is abstract, as in any class which inherits from an abstract class without overriding all its abstract methods. An abstract method is one which is declared (using the abstract keyword) but not defined - its up to the inheriting classes to actually define what the method is meant to do, by overriding it.

Also, what SYMM said. Surely you should be using an ActionListener for your buttons, and an ItemListener (or whatever theyre called, I havent done java for ages) for your lists?

edit: ButtonListeners and ListListeners arent defined in the 1.4.2 spec. Are these some homemade classes your professor wants to use or something?


edit2: actually, are buttonlistener and listlistener the names of your classes, or objects?

[NEWSBOT3]

Originally Posted by Nodrog

edit2: actually, are buttonlistener and listlistener the names of your classes, or objects?

inherited actionlistener classes at a guess.

[spunkie munkie]

erm

private class ListListener impements ActionListener

the full codes at http://root.djdemocracy.com/Jukebox.java if that would help

[pablissimo]

You spelt 'actionPerformed' incorrectly on the ButtonListener:

private class ButtonListener implements ActionListener
{
	public void ctionPerformed (ActionEvent event)
	{

becomes

private class ButtonListener implements ActionListener
{
	public void actionPerformed (ActionEvent event)
	{

Don't know if it'll fix it but it's a start.

[spunkie munkie]

id already fixed that one to no avail

really should of started work on this with more the two days till the deadline

[SYMM]

if you change "actionPerfomed" to "actionPerformed" it seems to work for me...

[spunkie munkie]

sorted

ta muchly

do you reckon its a good idea to give these forums a mention in the bibleography?

[NEWSBOT3]

no, as you cant quote non-specific authors.

[MT]

Originally Posted by NEWSBOT3

no, as you cant quote non-specific authors.

You certainly can, this is a web resource....