Re: J2ME - List and Font

On Tue, 20 Sep 2011 15:18:58 -0700, Roedy Green wrote:


Good point.


I think I should have been more clear about the fact, that this is j2me
code. The myListClass is extending the List class from
javax.microedition.lcdui.* and setFont() is a method to List.

http://java.sun.com/javame/reference/apis/jsr118/javax/microedition/lcdui/
List.html

I have uploaded the code to www.tj-software.dk/j2me/sms.zip.

And, I have found a solution to my problem, but I still don't understand
my original problem, so if someone can enlighten me, I would much
appreaciate.

So, if I do this:

Font f = Font.getFont(0, 0, Font.SIZE_LARGE);

msglist = new myListClass("messages");
/* appends elements to list here */
for (int i=0;i<msglist.size();i++) {
    msglist.setFont(i, f);
}
msglist.setCommandListener(this);
display.setCurrent(msglist);

then will all element in the list be with large font. That's good and
proves it's working.

But if I want to make my list class do the job of making the font large,
I (did) think I have to do something like this.

public final class myListClass extends List {
    rec_class recs;
    Vector data;
    Font f = Font.getFont(0, 0, Font.SIZE_LARGE);

    public myListClass (String lname)
    {
        super (lname, Choice.IMPLICIT);
        recs = new rec_class(lname);
        myRebuild();
    }

    public void myRebuild () {
        deleteAll();
        data = recs.getrecords();
        int i = 0;

        for (Enumeration e = data.elements(); e.hasMoreElements(); ) {
            append((String)e.nextElement(), null);
            setFont(i++, f);
        }
   }
}

It compile, but when running, it throws and exception -
"java.lang.ArrayIndexOutOfBoundsException". I expect the array is the
lists array of elements. I don't understand why there is a problem,
because after appending an element, I think it should be possible to use
to it.

But I found a solution -

        for (Enumeration e = data.elements(); e.hasMoreElements(); ) {
            append((String)e.nextElement(), null);
            //setFont(i++, f);
        }
    for (int i=0;i<size();i++) {
            setFont(i, f);
        }

ehhh, what? I have no idea why, but it works.

--
Thomas Jensen, Denmark