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Multi-Column JList

Auto Aligning columns of a JList which act as a single row

Submitted By: William_Wilson

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Rating:

Views: 9,446

Language: Java

Last Modified: March 29, 2006

Instructions: self contained code example, the pattern should be evident

Snippet

import java.io.*;
import java.awt.*;
import java.util.*;
import java.text.*;
import javax.swing.*;
import java.awt.event.*;
import javax.swing.event.*;
public class MultiColumn{
JFrame jf;
JScrollPane scroll;
JList list;
String[][] columnData;
public MultiColumn(){
//create the frame and JList JPanel
jf = new aFrame();
//create element List array
addElements();
//set list for JList
list.setListData(columnData);
//create Renderer and dislpay
list.setCellRenderer(new MyCellRenderer());
}
public void addElements(){
//first number is number of rows, second is number of columns
columnData = new String[4][3];
//static setting of String[][]
columnData[0][0] = "William";
columnData[0][1] = "A";
columnData[0][2] = "Wilson";
//dynamic setting of String[][]
for(int i=1;i<4;i++){
columnData[i][0] = "William";
columnData[i][1] = String.valueOf(i*13);
Calendar c = new GregorianCalendar();
columnData[i][2] = ((Date)c.getTime()).toString();
}
}
public class aFrame extends JFrame{
public aFrame(){
super("Multi-Column JList Example");
getContentPane().add(new PanelBuilder());
// display rules
setResizable(true);
setLocation(250,50);
setBackground(Color.lightGray);
setDefaultCloseOperation(EXIT_ON_CLOSE);
setSize(650, 400);
setVisible(true);
}
private class PanelBuilder extends JPanel{
public PanelBuilder(){
GridBagLayout layout = new GridBagLayout();
GridBagConstraints layoutConstraints = new GridBagConstraints();
setLayout(layout);
scroll = new JScrollPane();
list = new JList();
layoutConstraints.gridx = 0; layoutConstraints.gridy = 0;
layoutConstraints.gridwidth = 1; layoutConstraints.gridheight = 1;
layoutConstraints.fill = GridBagConstraints.BOTH;
layoutConstraints.insets = new Insets(1, 1, 1, 1);
layoutConstraints.anchor = GridBagConstraints.CENTER;
layoutConstraints.weightx = 1.0; layoutConstraints.weighty = 1.0;
scroll = new JScrollPane(list,JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED,
JScrollPane. HORIZONTAL_SCROLLBAR_NEVER);
layout.setConstraints(scroll, layoutConstraints);
add(scroll);
}
}
}
static class MyCellRenderer extends JPanel implements ListCellRenderer{
JLabel left, middle, right;
MyCellRenderer() {
setLayout(new GridLayout(1, 3));
left = new JLabel();
middle = new JLabel();
right = new JLabel();
left.setOpaque(true);
middle.setOpaque(true);
right.setOpaque(true);
add(left);
add(middle);
add(right);
}
public Component getListCellRendererComponent(JList list,Object value,int index,boolean isSelected,boolean cellHasFocus){
String leftData = ((String[])value)[0];
String middleData = ((String[])value)[1];
String rightData = ((String[])value)[2];
left.setText(leftData);
middle.setText(middleData);
right.setText(rightData);
if(isSelected){
left.setBackground(list.getSelectionBackground());
left.setForeground(list.getSelectionForeground());
middle.setBackground(list.getSelectionBackground());
middle.setForeground(list.getSelectionForeground());
right.setBackground(list.getSelectionBackground());
right.setForeground(list.getSelectionForeground());
}
else{
left.setBackground(list.getBackground());
left.setForeground(list.getForeground());
middle.setBackground(list.getBackground());
middle.setForeground(list.getForeground());
right.setBackground(list.getBackground());
right.setForeground(list.getForeground());
}
setEnabled(list.isEnabled());
setFont(list.getFont());
return this;
}
}
public static void main(String args[]){
MultiColumn jf = new MultiColumn();
}
}
/*I have found this useful on countless occassions, enjoy*/
/*William_Wilson. Â§*/

Copy & Paste

import java.io.*;
import java.awt.*; 
import java.util.*;
import java.text.*;
import javax.swing.*;
import java.awt.event.*;  
import javax.swing.event.*;

public class MultiColumn{
     
     JFrame           jf;
     JScrollPane scroll;
     JList          list;
     String[][]     columnData;
     
     public MultiColumn(){
          //create the frame and JList JPanel
          jf = new aFrame();
          //create element List array
          addElements();
          //set list for JList
          list.setListData(columnData);
          //create Renderer and dislpay
          list.setCellRenderer(new MyCellRenderer());
     }
     
     public void addElements(){
          //first number is number of rows, second is number of columns
          columnData = new String[4][3];
          //static setting of String[][]
          columnData[0][0] = "William";
          columnData[0][1] = "A";
          columnData[0][2] = "Wilson";
          //dynamic setting of String[][]
          for(int i=1;i<4;i++){
               columnData[i][0] = "William";
               columnData[i][1] = String.valueOf(i*13);
               Calendar c = new GregorianCalendar();
               columnData[i][2] = ((Date)c.getTime()).toString();
          }
     }
     
     public class aFrame extends JFrame{
          public aFrame(){
               super("Multi-Column JList Example");
               getContentPane().add(new PanelBuilder());
          
               // display rules
               setResizable(true);
               setLocation(250,50);
               setBackground(Color.lightGray);
             setDefaultCloseOperation(EXIT_ON_CLOSE);
             setSize(650, 400);
             setVisible(true);
          }
          private class PanelBuilder extends JPanel{
               public PanelBuilder(){
                    GridBagLayout layout = new GridBagLayout(); 
                    GridBagConstraints layoutConstraints = new GridBagConstraints(); 
                    setLayout(layout);
                    
                    scroll     = new JScrollPane();
                   list      = new JList();
                   layoutConstraints.gridx      = 0; layoutConstraints.gridy = 0; 
                    layoutConstraints.gridwidth = 1; layoutConstraints.gridheight = 1; 
                    layoutConstraints.fill           = GridBagConstraints.BOTH; 
                    layoutConstraints.insets      = new Insets(1, 1, 1, 1); 
                    layoutConstraints.anchor      = GridBagConstraints.CENTER; 
                    layoutConstraints.weightx      = 1.0; layoutConstraints.weighty = 1.0;
                    scroll = new JScrollPane(list,JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED,
                    JScrollPane. HORIZONTAL_SCROLLBAR_NEVER); 
                    layout.setConstraints(scroll, layoutConstraints);
                   add(scroll);
               }
          }
          
     }
     
     static class MyCellRenderer extends JPanel implements ListCellRenderer{
          JLabel left, middle, right;
          MyCellRenderer() {
               setLayout(new GridLayout(1, 3));
               left      = new JLabel();
               middle     = new JLabel();
               right      = new JLabel();
               left.setOpaque(true);
               middle.setOpaque(true);
               right.setOpaque(true);
               add(left);
               add(middle);
               add(right);
          }
          
          public Component getListCellRendererComponent(JList list,Object value,int index,boolean isSelected,boolean cellHasFocus){
               String leftData      = ((String[])value)[0];
               String middleData      = ((String[])value)[1];
               String rightData      = ((String[])value)[2];
               left.setText(leftData);
               middle.setText(middleData);
               right.setText(rightData);
               if(isSelected){
                    left.setBackground(list.getSelectionBackground());
                    left.setForeground(list.getSelectionForeground());
                    middle.setBackground(list.getSelectionBackground());
                    middle.setForeground(list.getSelectionForeground());
                    right.setBackground(list.getSelectionBackground());
                    right.setForeground(list.getSelectionForeground());
               }
               else{
                    left.setBackground(list.getBackground());
                    left.setForeground(list.getForeground());
                    middle.setBackground(list.getBackground());
                    middle.setForeground(list.getForeground());
                    right.setBackground(list.getBackground());
                    right.setForeground(list.getForeground());
               }
               setEnabled(list.isEnabled());
               setFont(list.getFont());
               return this;
          }
     }
     
     
     public static void main(String args[]){
          MultiColumn jf = new MultiColumn();
     }
     
}
/*I have found this useful on countless occassions, enjoy*/
/*William_Wilson. §*/