Referencing LOCAL SCOPE varible of outter class

Question

From inner class, I can reference the outter's class variable by OutterClassName.this.variableName. However, the variableName has LOCAL SCOPE, how do I access it?
Code sample:
for(int i=0; i<m_keyButton.length; i++)
m_keyButton.addMouseListener(new MouseAdapter() {
public void mouseEntered(MouseEvent e) {
if(m_keyButton[1].isEnabled())
m_feedbackScroll.setViewportView(m_mouseOverKeyImagePanel[i]);
Referencing i in m_mouseOverKeyImagePanel[i] causes an compile error:
"Acuity.java": local variable i is accessed from within inner class; needs to be declared final at line ...
Any quick solution? thanks a bunch.

Answer 1

The reason it has to be final is b'cos anonymous class
needs to know exactly what the value of i is at
compile-time. Unlike normal and inner classes, which
you could pass in the value via the constructor or
setter method at runtime, the only time for anonymous
classes could know the value is at compile-time.It's not really compile time. Adding the mouse listeners happens on the main thread. The code inside the listener runs on the event thread. The compiler just wants to make sure the variable isn't going to be changed by one thread or the other.
BTW: if(m_keyButton[j].isEnabled()) is kind of redundant. If the button isn't enabled, you won't get mouse events.