Local variable can't be accessed from inner class ???????? Why ??????
Plesae help, help, help. I have no idea what to do with this bug.........
<code>
for ( int i = 0; i <= 2; i++ ) {
for ( int j = 0; j <= 2; j++ ) {
grids[i][j] = new MyButton ();
grids[i][j].setBorder(but);
getContentPane().add(grids[i][j]);
MyButton sub = grids[i][j];
sub.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
if ( sub.getState() == 0 ) {
sub = new MyButton( (Icon) new ImageIcon(imageFile));
if ( imageFile.equals("cross.jpg") ) {
sub.changeState(1);
else {
sub.changeState(2);
</code>
The compiler complains that "sub" is in the inner class, which is the ActionListener class, must be declared final. Please tell me what to do with it. I want to add an ActionListener to each MyButton Object in the array. Thanks ......
OK, now I changed my code to this :
for ( int i = 0; i <= 2; i++ ) {
for ( int j = 0; j <= 2; j++ ) {
grids[i][j] = new MyButton ();
grids[i][j].setBorder(but);
getContentPane().add(grids[i][j]);
grids[i][j].addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
if ( grids[i][j].getState() == 0 ) {
grids[i][j] = new MyButton( (Icon) new ImageIcon(imageFile));
if ( imageFile.equals("cross.jpg") ) {
grids[i][j].changeState(1);
else {
grids[i][j].changeState(2);
[/cpde]
Thanks for your advice !!!!!!
Now the compiler says that i and j are local variables accessed from inner classes, needs to be declared final. How can I solve this then ???
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Accessing Enclosing Class Members From Inner Class Subclass
I have the following scenario that I cannot get to work. Notice the comments in B.doWork() for the problem code. In B.doWork(), how do I access m_strA?
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* Created on July 5, 2002, 2:20 PM
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return (sm_oInnerA);The whole point is that B is not an inner class of A
so it does not have access to A's member variables.
Eventhough B extends an inner class of A, that does
not make B an inner class of A. That is in the JLS,
but not so elegantly as I have put it, hehe.
If B were an innerclass of InnerA, then it would
qualify to access A's member variables.OK, I think that you are finally getting through to my thick skull on this one. Let me restate and get your check-off on my understanding of the situation.
The only classes with access to A's this reference are A and inner classes of A that are found within the definition of A. So, despite the fact that A and B are in the same package (and B should have access to A's non-private members because B and A are in the same package), and despite the fact that we would normally state that B "is a" InnerA (which is an inner class of A and would have access to a reference to the A.this reference), B is not allowed access to A.this (because B "is not really a" InnerA in the same way that the anonymous implementation of InnerA "is a" InnerA). However, nothing would prevent me from giving B access to a reference of the enclosing A as long as it was done via a method of InnerA, and as long as the implementation of that method is contained in A's implementation.
Does this "access" rule realy make sense? Are you aware of the justification for this rule? Or is the justification stated in the JLS? I would think that the compiler ought to be able to figure this kind of thing out and allow it. It seems to me the fact that I defined B in the way that I did, and the fact that B "is a" InnerA, implies that I desired a fairly tight relationship to A. In fact, I desired the exact relationship that exists for the anonymous implementation of InnerA.
The following is a modified version of my original example that runs as I originally wanted it to, but works around the access rules discussed on this forum thread:
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* Created on July 5, 2002, 2:20 PM
package Projects.InnerTrouble.Files;
public class A {
public abstract class InnerA {
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/** added to allow implementors of InnerA that are not enclosed in A's class definition to have access to the enclosing class */
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return (A.this);
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* @param args the command line arguments
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public B (A a)
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Hello,
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Hey everybody,
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I have a class
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Above class is only for an example to expalin my problem.
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Access to enclosing method fValues from the type A is emulated by a synthetic accessor method. Increasing its visibility will improve your performance
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miromiro_connect wrote:
I have a class
class A{
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Above class is only for an example to expalin my problem.
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Access to enclosing method fValues from the type A is emulated by a synthetic accessor method. Increasing its visibility will improve your performance
I order to get rid of this warning I must make fValues public is this the only solution ?
miroWhat happens if you remove the modifier? (That is uses default) -
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from jpf i am calling java class which inturn calls jcx and
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Unfortunately in the current release controls cannot be accessed from stand
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"sridhar" <[email protected]> wrote in message
news:4083d449$[email protected]..
>
Is it possible to access jcx from java class ?
from jpf i am calling java class which inturn calls jcx and
i am getting nullpointer exception at jcx call in java class
waiting for solution...
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sridhar -
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I have a class Solution, which defines an inner class, SolutionStep.
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Any help appreciated.Yes, you're right, I dropped a parenthesis. Sorry.
The offending statement is actually
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The following code demonstrates this....
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