h:selectManyListbox editing

Do you understand NullPointerExceptions? This will occur if you invoke an action on an object which isn't instantiated yet. In this case you're invoking an action on stage using addAll() and not on list. So checking the contents of list is totally irrelevant.

Just instantiate the stage object.

private List stage = new ArrayList();

BalusCa at 2007-7-9 5:04:54 >

Hi BalusC,

Thanks a lot for your help.

on google I got link regarding same issue.

http://balusc.xs4all.nl/frm/list_message/21777

Here you wrote method as,

public void leftToRight() {

if (selectedItemsLeft != null) {

for (Iterator iter = selectItemsLeft.iterator(); iter.hasNext();) {

SelectItem selectItem = (SelectItem) iter.next();// Can you please tell me why this SelectItem is here . if (selectedItemsLeft.contains(selectItem.getValue())) {

selectItemsRight.add(selectItem);

iter.remove();

}

Thanks

sandip_03_jsfa at 2007-7-9 5:04:54 >

Hi BalusC,

SelectItem selectItem = (SelectItem) iter.next();

If I use it then I am not able to display selected list.

But if I do ,

String st = (String)iter.next();

if (li.toString.contains(st) {

stage.add(st);

}

Here I am able to display list.

But still problem there as I am using contains, Suppose there are list as,A,B,C,A-B,D,E.

So while saving if I selected A,E, then at time of editing it will display me A,E,A-B (as A-B contains letter A)

Thanks

sandip_03_jsfa at 2007-7-9 5:04:54 >

Hi,

I agree with you that you are itearationg through selectItems

But in my case I am doing as,

List allstages = all values from Databse i.e.A,B,C,A-B,D,E

List li = here I m retriving saved values i.e. A,C

if (li != null) {

for (Iterator iter = allstages.iterator(); iter.hasNext();) {

String mystage = (String) iter.next(); // Here I used String

if (li.toString().contains(mystage)) {

stage.add(mystage);

}

}

}

I saved A,C but while editing its also displaying A-B i.e. A,C,A-B

If I try to use SelectItem instead String nothing is in selected mode.

Thanks again

sandip_03_jsfa at 2007-7-9 5:04:54 >

Hi Sandip

I did out your example and didn't get that error. i.e. I got only A and C

Here is the code I used:

import java.util.Iterator;

public class TestContains

{

/**

* @param args

*/

public static void main(String[] args)

{

// TODO Auto-generated method stub

ArrayList first = new ArrayList();

ArrayList second = new ArrayList();

ArrayList third = new ArrayList();

first.add("a");

first.add("b");

first.add("a-b");

first.add("c");

second.add("a");

second.add("c");

if (second != null)

{

for (Iterator iter = first.iterator(); iter.hasNext();)

{

String mystage = (String) iter.next(); // Here I used String

if (second.toString().contains(mystage))

{

third.add(mystage);

}

}

}

for (Iterator iter = third.iterator(); iter.hasNext();)

{

System.out.println(iter.next());

}

}

}

This prints out only A and C, I don't see how it could print out A-B.

Could your error be caused by using List and not ArrayList perhaps? Are your lists are not being cleaned after each use?

Cheers,

Illu

Message was edited by:

Illu

Illua at 2007-7-9 5:04:55 >