My first menu: biting me in the Act..

Question

..ionListener() . It's about time I added a menu to my [url http://r0k.us/graphics.SIHwheel.html]Interactive Color Wheel. Having never done menus in Java before, it's fighting me every stop of the way, even with the help of the tutorial. The good news is: I can build a menu that displays what I want, even if it looks funky. The bad news is: I cannot get it to do anything. I have tried two methods:
----- CNDfilelist.properties -----
CND.file.01 = cnd_ntc.properties
CND.name.01 = Name that Color
CND.file.02 = cnd_resene2010.properties
CND.name.02 = Resene 2010
CND.file.03 = cnd_w3c.properties
CND.name.03 = W3C Colors
----- from my pane constructor -----
     readCNDnames();  // successfully reads in the above
     JRadioButtonMenuItem item;
     ButtonGroup g = new ButtonGroup();
     JMenuBar menuBar = new JMenuBar();
     menuBar.setBorderPainted(false);
     menuBar.setPreferredSize(new Dimension(200, 14));
     JMenu dictionary = new JMenu("Color Lists");
     for (int i = 0; i < cndFileCount; i++) {
         item = new JRadioButtonMenuItem(cndFileList[1]);
     item.setActionCommand("cnd");
//     item.addActionListener( new ActionListener() {
//          public void actionPerformed(ActionEvent e) {
//          changeCND(cndFileList[i][0]);
     if (i == 0) item.setSelected(true);
     g.add(item);
     dictionary.add(item);
     menuBar.add(dictionary);
     JMenu about = new JMenu("About");
     menuBar.add(about);
     add(menuBar, BorderLayout.PAGE_START);
Two action methods have been attempted, traditional switchboard and anonymous. I've been using the switchboard approach, but with these JRadioButtonMenuItems I don't know what to put into the "cnd" clause of the class actionPerformed() method. It needs to load one of some indeterminate-until-runtime number color name dictionaries (from 1 to 99), but I don't know how to track back to see which actual item were selected. Alternatively, I could give each button a unique setActionCommand("cnd01"), ("cnd02"), etc., but i cannot imagine an elegant way to code for a variable number of such possiblities in the actionPerformed().
So, that brings me to the anonymous listener approach, commented-out above. The problem is that the local variable i isn't actually available to the anonymous listener. The compiler complains:
D:\progming\java\SIHwheel>javac -target 1.4 -source 1.4 SIHwheel.java
SIHwheel.java:645: local variable i is accessed from within inner class; needs t
o be declared final
                    changeCND(cndFileList[0]);
^
1 error
The message is actually funny; the very last thing i can be is final. There has got to be an elegant method to do this. What am I misssing?
My other problem is the flow manager for the pane. I cannot seem to find the right one for what I need. I've tried several and am currently using :
//     this.setLayout(new GridLayout(5, 1));
     this.setLayout(new BoxLayout(this, BoxLayout.Y_AXIS));
//     this.setLayout(new BorderLayout());
//     this.setLayout(new GridBagLayout());I've even tried more than that, but the least problematic is the BoxLayout(). Here is a little picture:
* http://r0k.us/rock/junk/SIHmenu.png
The one problem BoxLayout is giving me is that it refuses to make the menu bar full pane width. You can see in the first code box that i'm telling it to be 200 wide, but it won't. It will change height, no problem, but not width. I've even tried adding:
* menuBar.setMinimumSize(new Dimension(200, 14));
but the width on that is ignored as well. You can see a remnant of my BorderLayout() attempt in
* add(menuBar, BorderLayout.PAGE_START);
BoxLayout ignores the 2nd parameter. BorderLayout gives me a full-width menu bar! But it funkily hides 2 of the pane's 5 components. They are supposed to lay right on top of each other:
     add(menuBar, BorderLayout.PAGE_START);
     add(sorts, BorderLayout.LINE_START);
     add(new JScrollPane(list), BorderLayout.LINE_START);
     add(spotPanel, BorderLayout.LINE_START);
     add(hexPanel, BorderLayout.PAGE_END);Instead it looks like this:
* http://r0k.us/rock/junk/SIHborderLayoutProblem.png
with both the sorts and scrollable list panel missing entirely. Only Spot, the Magic Color Dog comes out unscathed, but then, he's magic.
In short, without the menuBar, BoxLayout was fine. But add the menBar , and BoxLayout refuses to do full pane width. Sigh, I think I'm going to take a nap -- been up since 4am.

Answer 1

RichF wrote:
     JRadioButtonMenuItem item;
     ButtonGroup g = new ButtonGroup();
     JMenuBar menuBar = new JMenuBar();
     menuBar.setBorderPainted(false);
     menuBar.setPreferredSize(new Dimension(200, 14));
     JMenu dictionary = new JMenu("Color Lists");
     for (int i = 0; i < cndFileCount; i++) {
         final int j = i;  // magic necessary for anonymous actionPerformed
         item = new JRadioButtonMenuItem(cndFileList[1]);
     item.addActionListener( new ActionListener() {
          public void actionPerformed(ActionEvent e) {
          changeCND(cndFileList[j][0]);
     if (i == 0) item.setSelected(true);
     g.add(item);
     dictionary.add(item);
     menuBar.add(dictionary);
You might find it easier to work wirh a [url http://tips4java.wordpress.com/2008/11/09/select-button-group/]Select Button Group[/url] which has methods for <tt>addPropertyChangeListener(...)</tt> and <tt>getSelectedIndex()</tt> that would allow you to write more concise code.
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