Solved

Java JList issue

Posted on 2011-09-12
7
351 Views
Last Modified: 2012-05-12
I've added the following code to a JList and am now unable to select individual items in the list

Any Ideas? For reference getANZIC returns a string value
@SuppressWarnings("serial")
class MyCellRenderer extends JLabel implements ListCellRenderer {

public Component getListCellRendererComponent(
      JList list,
      Object value,            // value to display
      int index,               // cell index
      boolean isSelected,      // is the cell selected
      boolean cellHasFocus)    // the list and the cell have the focus
    {
	
    
        setText(((Occupation)value).getANZIC());
        return this;
    }
}

Open in new window

0
Comment
Question by:CloudStrife209
  • 5
  • 2
7 Comments
 
LVL 47

Expert Comment

by:for_yan
ID: 36526932


>I've added the following code to a JList

Please, post your code the part were you craete the list and set the renderer
0
 

Author Comment

by:CloudStrife209
ID: 36526937
here you go
JList listing = new JList(occupationList);
listing.setCellRenderer(new MyCellRenderer());

Open in new window

0
 
LVL 47

Expert Comment

by:for_yan
ID: 36526953
What means unable to select?
How do you judge that it is not selecting?

Can you post more of your code so that I copuld try
to run it myself?
0
Technology Partners: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

 
LVL 47

Expert Comment

by:for_yan
ID: 36527024
It would work if you extend DefaultListCellRenderer.
Try this code:

import javax.swing.*;
import java.awt.*;
import java.util.ArrayList;
import java.util.Vector;

public class JListTest extends JFrame {

    public JListTest() {
        super("test");

        Vector<Occupation> ar = new Vector<Occupation>();
      ar.add(new Occupation("MD"));
       ar.add(new Occupation("PD"));
       ar.add(new Occupation("LD"));

        JList l = new JList(ar);
        l.setCellRenderer(new MyCellRenderer());

        Container c = this.getContentPane();
        c.add(l);

        this.setSize(300,300);
        this.setVisible(true);





    }

    public static void main(String[] args) {
        new JListTest();
    }

}
class Occupation {
    String text;

    Occupation(String s){
        text = s;
    }

    public String toString(){
        return text;
    }

}

@SuppressWarnings("serial")
class MyCellRenderer extends  DefaultListCellRenderer{

public Component getListCellRendererComponent(
      JList list,
      Object value,            // value to display
      int index,               // cell index
      boolean isSelected,      // is the cell selected
      boolean cellHasFocus)    // the list and the cell have the focus
    {

          System.out.println("value: " + value);
          System.out.println(isSelected);
           System.out.println(cellHasFocus);

        if(isSelected)this.setBackground(Color.blue);
        else    this.setBackground(Color.white);
       this.setText(((Occupation)value).toString());
        return this;
    }
}

Open in new window

0
 
LVL 47

Accepted Solution

by:
for_yan earned 500 total points
ID: 36527059
This is another variant how it works:

import javax.swing.*;
import java.awt.*;
import java.util.ArrayList;
import java.util.Vector;

public class JListTest extends JFrame {

    public JListTest() {
        super("test");

        Vector<Occupation> ar = new Vector<Occupation>();
      ar.add(new Occupation("MD"));
       ar.add(new Occupation("PD"));
       ar.add(new Occupation("LD"));

        JList l = new JList(ar);
        l.setCellRenderer(new MyCellRenderer1());

        Container c = this.getContentPane();
        c.add(l);

        this.setSize(300,300);
        this.setVisible(true);





    }

    public static void main(String[] args) {
        new JListTest();
    }

}
class Occupation {
    String text;

    Occupation(String s){
        text = s;
    }

    public String toString(){
        return text;
    }

}



class MyCellRenderer1 extends JLabel implements ListCellRenderer {

  public MyCellRenderer1() {
    setOpaque(true);
  }

  public Component getListCellRendererComponent(JList list, Object value, int index,
      boolean isSelected, boolean cellHasFocus) {
    setText(value.toString());

    if (isSelected) {
      setBackground(list.getSelectionBackground());
      setForeground(list.getSelectionForeground());
    } else {
      setBackground(list.getBackground());
      setForeground(list.getForeground());
    }
    return this;
  }
}

Open in new window

0
 
LVL 47

Expert Comment

by:for_yan
ID: 36527075
This is based on your code and it is working.

You of course need to add if(isSelected)... else
and another thing which turns out to be impiortnat
is setOpaque(true) in the constructor.

import javax.swing.*;
import java.awt.*;
import java.util.ArrayList;
import java.util.Vector;

public class JListTest extends JFrame {

    public JListTest() {
        super("test");

        Vector<Occupation> ar = new Vector<Occupation>();
      ar.add(new Occupation("MD"));
       ar.add(new Occupation("PD"));
       ar.add(new Occupation("LD"));

        JList l = new JList(ar);
        l.setCellRenderer(new MyCellRenderer());

        Container c = this.getContentPane();
        c.add(l);

        this.setSize(300,300);
        this.setVisible(true);





    }

    public static void main(String[] args) {
        new JListTest();
    }

}
class Occupation {
    String text;

    Occupation(String s){
        text = s;
    }

    public String toString(){
        return text;
    }

}




class MyCellRenderer extends JLabel implements ListCellRenderer {
     public MyCellRenderer() {
    setOpaque(true);
  }

public Component getListCellRendererComponent(
      JList list,
      Object value,            // value to display
      int index,               // cell index
      boolean isSelected,      // is the cell selected
      boolean cellHasFocus)    // the list and the cell have the focus
    {
         
         if (isSelected) {
      setBackground(Color.blue);
      setForeground(Color.black);
    } else {
      setBackground(Color.white);
      setForeground(Color.black);
    }

        setText(((Occupation)value).toString());
        return this;
    }
}

Open in new window

0
 

Author Closing Comment

by:CloudStrife209
ID: 36527082
Thanks
0

Featured Post

Industry Leaders: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
servlet filter example 37 82
login jsp example 24 84
hibernate jars 4 57
Hibernate Inheritance Strategy for Abstract Base class and two concrete classes 3 16
For beginner Java programmers or at least those new to the Eclipse IDE, the following tutorial will show some (four) ways in which you can import your Java projects to your Eclipse workbench. Introduction While learning Java can be done with…
Java Flight Recorder and Java Mission Control together create a complete tool chain to continuously collect low level and detailed runtime information enabling after-the-fact incident analysis. Java Flight Recorder is a profiling and event collectio…
Viewers learn about the “for” loop and how it works in Java. By comparing it to the while loop learned before, viewers can make the transition easily. You will learn about the formatting of the for loop as we write a program that prints even numbers…
Viewers learn how to read error messages and identify possible mistakes that could cause hours of frustration. Coding is as much about debugging your code as it is about writing it. Define Error Message: Line Numbers: Type of Error: Break Down…

685 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question