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LookAndFeel blocking JComboBox background change?

The goal is to change the background of all combo box when LookAndFeel is in the main method.
But I get different results when LookAndFeel exists and not.
Without LookAndFeel: JComboBox is visible after JFrame resizing
import javax.swing.*;
import java.awt.*;
import static java.awt.Color.WHITE;
public class TestFrame extends JFrame {
private static final String[] ANIMALS = new String[]{"Cat", "Mouse", "Dog", "Elephant", "Bird", "Goat", "Bear"};
public TestFrame() {
setSize(600, 300);
setVisible(true);
setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
JPanel panel = new JPanel();
JComboBox<String> comboBox = new JComboBox<>();
comboBox.setModel(new DefaultComboBoxModel<>(ANIMALS));
comboBox.setForeground(WHITE);
comboBox.setBackground(new Color(71, 81, 93));
comboBox.getEditor().getEditorComponent().setBackground(new Color(71, 81, 93));
comboBox.getEditor().getEditorComponent().setForeground(WHITE);
comboBox.setRenderer(new DefaultListCellRenderer() {
#Override
public void paint(Graphics g) {
setBackground(new Color(71, 81, 93));
setForeground(WHITE);
super.paint(g);
}
});
panel.add(comboBox);
add(panel);
}
public static void main(String[] args) {
new TestFrame();
}
}
With LookAndFeel:
import javax.swing.*;
import java.awt.*;
import java.util.logging.Level;
import java.util.logging.Logger;
import static java.awt.Color.WHITE;
public class TestFrame extends JFrame {
private static final String[] ANIMALS = new String[]{"Cat", "Mouse", "Dog", "Elephant", "Bird", "Goat", "Bear"};
public TestFrame() {
setSize(600, 300);
setVisible(true);
setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
JPanel panel = new JPanel();
JComboBox<String> comboBox = new JComboBox<>();
comboBox.setModel(new DefaultComboBoxModel<>(ANIMALS));
comboBox.setForeground(WHITE);
comboBox.setBackground(new Color(71, 81, 93));
comboBox.getEditor().getEditorComponent().setBackground(new Color(71, 81, 93));
comboBox.getEditor().getEditorComponent().setForeground(WHITE);
comboBox.setRenderer(new DefaultListCellRenderer() {
#Override
public void paint(Graphics g) {
setBackground(new Color(71, 81, 93));
setForeground(WHITE);
super.paint(g);
}
});
panel.add(comboBox);
add(panel);
}
public static void main(String[] args) {
try {
for (UIManager.LookAndFeelInfo info : UIManager.getInstalledLookAndFeels()) {
if ("Nimbus".equals(info.getName())) {
UIManager.setLookAndFeel(info.getClassName());
break;
}
}
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
Logger.getLogger(TestFrame.class.getName()).log(Level.SEVERE, null, ex);
}
/* Create and display the form */
EventQueue.invokeLater(new Runnable() {
public void run() {
new TestFrame();
}
});
}
}
How can I achieve full painting of the combo box with LookAndFeel enabled?

There is no thing like a disabled or enabled LookAndFeel. You always have a Look and feel set in your aplication. You just seem to set another LookAndFeel, which in your case is Nimbus. However, to answer your question, Nimbus sets the DefaultListCellRenderer's opacity-Property to false, (MetalLookAndFeel for example sets it to true) which is the reason for the visual representation you are showing. You should be able to fix this by overriding the getListCellRendererComponent method of DefaultListCellRenderer like so:
#Override
public Component getListCellRendererComponent(JList list, Object value,
int index, boolean isSelected, boolean cellHasFocus) {
JComponent comp = (JComponent) super.getListCellRendererComponent(list,
value, index, isSelected, cellHasFocus);
list.setBackground(COMBO_COLOR);
list.setForeground(Color.WHITE);
list.setOpaque(false);
return comp;
}
You also have to set the UIManagers property ComboBox.forceOpaque to false, like so:
UIManager.put("ComboBox.forceOpaque", false);
A full list of the Nimubs defauts can be found here.
A full working example of the fixed problem if needed:
import java.awt.*;
import java.util.Arrays;
import javax.swing.*;
public class JComboBoxExample {
private static final Color COMBO_COLOR = new Color(71, 81, 93);
private static final String[] COMBO_DATA = {"Get back!", "Go!", "Help!", "Careful!"};
public static void main(String[] args) throws Exception {
String nimbus = Arrays.asList(UIManager.getInstalledLookAndFeels())
.stream()
.filter(i -> i.getName().equals("Nimbus"))
.findFirst()
.get()
.getClassName();
UIManager.setLookAndFeel(nimbus);
UIManager.put("ComboBox.forceOpaque", false);
JFrame jf = new JFrame();
jf.setVisible(true);
jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
jf.setLocationRelativeTo(null);
MyComboBox comboBox = new MyComboBox(new DefaultComboBoxModel(COMBO_DATA));
jf.add(comboBox);
jf.pack();
}
private static class MyComboBox extends JComboBox {
public MyComboBox(DefaultComboBoxModel model) {
super(model);
setForeground(Color.WHITE);
setFont(new Font("Arial", Font.PLAIN, 30));
setPreferredSize(new Dimension(350, 50));
setRenderer(new MyRenderer());
}
}
private static class MyRenderer extends DefaultListCellRenderer {
#Override
public Component getListCellRendererComponent(JList list, Object value,
int index, boolean isSelected, boolean cellHasFocus) {
JComponent comp = (JComponent) super.getListCellRendererComponent(list,
value, index, isSelected, cellHasFocus);
list.setBackground(COMBO_COLOR);
list.setForeground(Color.WHITE);
list.setOpaque(false);
return comp;
}
}
}
results in:
By the way, I figured this out by using the visual debugger of the NetBeans IDE.

How to change font of JComboBox

I want to change the font size of my JComboBox.
However only not selected item are change, like that :
https://imgur.com/a/WnnyPA6
So I want that selected item are also bold.
I done a custom combobox classe like that :
public class CustomComboBox extends JLabel implements ListCellRenderer {
public Component getListCellRendererComponent(
JList list,
Object value,
int index,
boolean isSelected,
boolean cellHasFocus) {
JLabel label = new JLabel(){
public Dimension getPreferredSize(){
return new Dimension(200, 80);
}
};
label.setText(String.valueOf(value));
label.setFont(new Font("Serif", Font.BOLD, 30));
return label;
}
}

You can simply set font for combo box. Something like this:
import java.awt.Dimension;
import java.awt.Font;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.SwingUtilities;
import javax.swing.WindowConstants;
import javax.swing.plaf.basic.BasicComboBoxRenderer;
/**
* <code>ComboTest</code>.
*/
public class ComboTest {
public static void main(String[] args) {
SwingUtilities.invokeLater(new ComboTest()::startUp);
}
private void startUp() {
JComboBox<String> combo = new JComboBox<>(new String[] {"A", "B", "C"});
combo.setFont(new Font("Serif", Font.BOLD, 30));
combo.setRenderer(new ComboRenderer());
JFrame frm = new JFrame("Combo test");
frm.add(combo);
frm.pack();
frm.setDefaultCloseOperation(WindowConstants.DISPOSE_ON_CLOSE);
frm.setLocationRelativeTo(null);
frm.setVisible(true);
}
private static class ComboRenderer extends BasicComboBoxRenderer {
#Override
public Dimension getPreferredSize() {
return new Dimension(200, 80);
}
}
}
When my suggstion is not helpful in your case please create a small runnable example, so we can also start and debug it.

You can set font for Combo box by using
combo.setFont(new FontUIResource("Roboto",Font.PLAIN,12);

How to programmatically access the display field of a JComboBox? [duplicate]

I am programming an editable combobox in a JFrame Form, but i want to change te background color.
How the program works:
If i click the button "press", then the combobox his background needs to become black.
I tried:
1.
cbo.setBackground(Color.BLACK);
But it did nothing
2
cbo.getEditor().getEditorComponent().setBackground(Color.BLACK);
((JTextField) cbo.getEditor().getEditorComponent()).setOpaque(true);
Does this:
Code example:
public class NewJFrame extends javax.swing.JFrame {
private JComboBox cboCategorie;
public NewJFrame() {
initComponents();
cboCategorie = new JComboBox();
cboCategorie.setBounds(10, 10, 250, 26);
cboCategorie.setVisible(true);
cboCategorie.setEditable(true);
this.add(cboCategorie);
}
private void pressActionPerformed(java.awt.event.ActionEvent evt) {
cboCategorie.getEditor().getEditorComponent().setBackground(Color.BLACK);
((JTextField) cboCategorie.getEditor().getEditorComponent()).setOpaque(true);
}
I am working with the Java JDK7
Any sugestions?

see my code example
import java.awt.*;
import java.util.Vector;
import javax.swing.*;
import javax.swing.UIManager;
import javax.swing.plaf.ColorUIResource;
import javax.swing.plaf.metal.MetalComboBoxButton;
public class MyComboBox {
private Vector<String> listSomeString = new Vector<String>();
private JComboBox someComboBox = new JComboBox(listSomeString);
private JComboBox editableComboBox = new JComboBox(listSomeString);
private JComboBox non_EditableComboBox = new JComboBox(listSomeString);
private JFrame frame;
public MyComboBox() {
listSomeString.add("-");
listSomeString.add("Snowboarding");
listSomeString.add("Rowing");
listSomeString.add("Knitting");
listSomeString.add("Speed reading");
//
someComboBox.setPrototypeDisplayValue("xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx");
someComboBox.setFont(new Font("Serif", Font.BOLD, 16));
someComboBox.setEditable(true);
someComboBox.getEditor().getEditorComponent().setBackground(Color.YELLOW);
((JTextField) someComboBox.getEditor().getEditorComponent()).setBackground(Color.YELLOW);
//
editableComboBox.setPrototypeDisplayValue("xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx");
editableComboBox.setFont(new Font("Serif", Font.BOLD, 16));
editableComboBox.setEditable(true);
JTextField text = ((JTextField) editableComboBox.getEditor().getEditorComponent());
text.setBackground(Color.YELLOW);
JComboBox coloredArrowsCombo = editableComboBox;
Component[] comp = coloredArrowsCombo.getComponents();
for (int i = 0; i < comp.length; i++) {// hack valid only for Metal L&F
if (comp[i] instanceof MetalComboBoxButton) {
MetalComboBoxButton coloredArrowsButton = (MetalComboBoxButton) comp[i];
coloredArrowsButton.setBackground(null);
break;
}
}
//
non_EditableComboBox.setPrototypeDisplayValue("xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx");
non_EditableComboBox.setFont(new Font("Serif", Font.BOLD, 16));
//
frame = new JFrame();
frame.setLayout(new GridLayout(0, 1, 10, 10));
frame.add(someComboBox);
frame.add(editableComboBox);
frame.add(non_EditableComboBox);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLocation(100, 100);
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
UIManager.put("ComboBox.background", new ColorUIResource(Color.yellow));
UIManager.put("JTextField.background", new ColorUIResource(Color.yellow));
UIManager.put("ComboBox.selectionBackground", new ColorUIResource(Color.magenta));
UIManager.put("ComboBox.selectionForeground", new ColorUIResource(Color.blue));
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
MyComboBox aCTF = new MyComboBox();
}
});
}
}

Turned out to be easy. Create a renderer and set the background color. Then override the renderer's setOpaque method to always set the opacity to true.
class PDFChooser extends JComboBox<String> {
PDFChooser() {
setRenderer(new Renderer());
}
class Renderer extends DefaultListCellRenderer {
#Override
public void setOpaque(boolean makeBackGroundVisible) {
super.setOpaque(true); // THIS DOES THE TRICK
}
#Override
public Component getListCellRendererComponent(JList<?> list,
Object value, int index,
boolean isSelected, boolean cellHasFocus) {
setText((String)value);
setBackground(Color.cyan);
return this;
}
}
}
If you want the popup menu to use the LAF background, you can add a PopupMenuListener to note when the popup is popped. At that time, the setOpaque method would set the opacity false.

It works for me to change the color of a selected item in JComboBox.
JComboBox cmb = new JComboBox();
cmb.setEditable(true);
cmb.setEditor(new WComboBoxEditor(getContentPane().getBackground()));
// To change the arrow button's background
cmb.setUI(new BasicComboBoxUI(){
protected JButton createArrowButton()
{
BasicArrowButton arrowButton = new BasicArrowButton(BasicArrowButton.SOUTH, null, null, Color.GRAY, null);
return arrowButton;
}
});
cmb.setModel(new DefaultComboBoxModel(new String[] { "a", "b", "c" }));
import java.awt.Color;
import java.awt.Component;
import java.awt.event.ActionListener;
import javax.swing.ComboBoxEditor;
import javax.swing.JTextField;
public class WComboBoxEditor implements ComboBoxEditor
{
JTextField tf;
public WComboBoxEditor(Color background)
{
tf = new JTextField();
tf.setBackground(background);
tf.setBorder(null);
}
public Component getEditorComponent()
{
return tf;
}
public void setItem(Object anObject)
{
if (anObject != null)
{
tf.setText(anObject.toString());
}
}
public Object getItem()
{
return tf.getText();
}
public void selectAll()
{
tf.selectAll();
}
public void addActionListener(ActionListener l)
{
tf.addActionListener(l);
}
public void removeActionListener(ActionListener l)
{
tf.removeActionListener(l);
}
}
If you'd like to change the color of items in JCombobox except for a selected one, customize ListCellRenderer.

Change color of selection (after selection) in a JComboBox

I'm writing a GUI using Swing. I have a custom written JComboBox using a ListCellRenderer and a BasicComboBoxEditor.
In my getListCellRendererComponent() method I change the color of the the list based on whether the item is "selected" (mouse is hovering above), which is nice and all, but I don't want the selection to change background color once a choice is made, which it currently does.
The first picture shows how the interface looks before a selection is made, and the second one shows how it looks after.
QUESTION
How do I change the background of the "selection" to the "stockColor"?
MCVE
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.util.Vector;
import javax.swing.DefaultComboBoxModel;
import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JList;
import javax.swing.JPanel;
import javax.swing.ListCellRenderer;
import javax.swing.plaf.basic.BasicComboBoxEditor;
public class TFComboBox extends JComboBox{
public static void main(String[] args){
createAndShowGUI();
}
public static void createAndShowGUI(){
JFrame frame = new JFrame("MCVE");
JPanel pane = new JPanel(new BorderLayout());
TFComboBox cb = new TFComboBox();
boolean[] tf = {true, false};
cb.addItems(tf);
JButton b = new JButton("Click me!");
pane.add(cb, BorderLayout.CENTER);
pane.add(b, BorderLayout.LINE_END);
frame.add(pane);
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setVisible(true);
}
private DefaultComboBoxModel model;
private Vector<Boolean> comboBoxItems;
private JComboBox comboBox;
public TFComboBox(){
comboBoxItems = new Vector<Boolean>();
comboBoxItems.add(Boolean.TRUE);
comboBoxItems.add(Boolean.FALSE);
comboBox = new JComboBox(comboBoxItems);
model = new DefaultComboBoxModel();
setModel(model);
setRenderer(new TrueFalseComboRenderer());
setEditor(new TrueFalseComboEditor());
}
public void addItems(boolean[] items){
for(boolean anItem : items){
model.addElement(anItem);
}
}
}
class TrueFalseComboRenderer extends JPanel implements ListCellRenderer {
private JLabel labelItem = new JLabel();
private Color stockColor = labelItem.getBackground();
public TrueFalseComboRenderer(){
setLayout(new BorderLayout());
labelItem.setOpaque(true);
labelItem.setHorizontalAlignment(JLabel.CENTER);
add(labelItem);
setBackground(Color.LIGHT_GRAY);
}
#Override
public Component getListCellRendererComponent(JList list, Object value,
int index, boolean isSelected, boolean cellHasFocus) {
boolean tempValue = (boolean) value;
labelItem.setText(Boolean.toString(tempValue));
if(isSelected){
labelItem.setBackground(stockColor.darker());
labelItem.setForeground(Color.WHITE);
} else {
labelItem.setBackground(stockColor);
labelItem.setForeground(Color.BLACK);
}
return this;
}
}
class TrueFalseComboEditor extends BasicComboBoxEditor {
private JLabel labelItem = new JLabel();
private JPanel panel = new JPanel();
private Object selectedItem;
public TrueFalseComboEditor() {
labelItem.setOpaque(false);
labelItem.setHorizontalAlignment(JLabel.CENTER);
labelItem.setForeground(Color.WHITE);
panel.setLayout(new FlowLayout(FlowLayout.LEFT, 5, 2));
panel.setBackground(Color.BLUE);
panel.add(labelItem);
}
public Component getEditorComponent(){
return this.panel;
}
public Object getItem(){
return this.selectedItem;
}
public void setItem(Object item){
if(item == null){
return;
}
this.selectedItem = item;
labelItem.setText(item.toString());
}
}
EDIT
I've added a MCVE and as you can see it is the "problem" that the JComboBox is focused that has to do with my issue. I've placed a button next to the ComboBox to help with removing the focus from the ComboBox.
Simply doing a setFocusable(false) would fix it, but also take away some of the functionality of the rest of the program, so this is not desired.

for better help sooner post an SSCCE / MCVE, short, runnable, compilable, with hardcoded value for JComboBox / XxxComboBoxModel in local variable
JList has Boolean array implemented as default in API (no idea whats hidden in
String trueFalseItem = Boolean.toString(tempValue); and with value stored JComboBox model)
this is just code minimum to test isSelected and to change JList.setSelectionXxx inside DefaultListCellRenderer
for example (code in SSCCE / MCVE form)
.
.
import java.awt.Color;
import java.awt.Component;
import java.awt.event.ActionEvent;
import java.util.Vector;
import javax.swing.AbstractAction;
import javax.swing.Action;
import javax.swing.DefaultListCellRenderer;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JList;
import javax.swing.SwingUtilities;
public class ComboBoxBooleanModel {
private javax.swing.Timer timer = null;
private Vector<Boolean> comboBoxItems;
private JComboBox box;
public ComboBoxBooleanModel() {
comboBoxItems = new Vector<Boolean>();
comboBoxItems.add(Boolean.TRUE);
comboBoxItems.add(Boolean.FALSE);
box = new JComboBox(comboBoxItems);
box.setRenderer(new DefaultListCellRenderer() {
#Override
public Component getListCellRendererComponent(JList list, Object value,
int index, boolean isSelected, boolean cellHasFocus) {
Component c = super.getListCellRendererComponent(
list, value, index, isSelected, cellHasFocus);
if (c instanceof JLabel) {
JLabel l = (JLabel) c;
if (Boolean.TRUE.equals(value)) {
l.setBackground(Color.RED);
if (isSelected) {
list.setSelectionForeground(Color.RED);
list.setSelectionBackground(Color.BLUE);
}
} else if (Boolean.FALSE.equals(value)) {
l.setBackground(Color.BLUE);
if (isSelected) {
list.setSelectionForeground(Color.BLUE);
list.setSelectionBackground(Color.RED);
}
}
return l;
}
return c;
}
});
JFrame frame = new JFrame("");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(box);
frame.setLocationRelativeTo(null);
frame.pack();
frame.setVisible(true);
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
box.setSelectedIndex(1);
}
});
start();
}
private void start() {
timer = new javax.swing.Timer(2250, updateCol());
timer.start();
}
public Action updateCol() {
return new AbstractAction("text load action") {
private static final long serialVersionUID = 1L;
#Override
public void actionPerformed(ActionEvent e) {
if (box.getSelectedItem() == (Boolean) false) {
box.setSelectedItem((Boolean) true);
} else {
box.setSelectedItem((Boolean) false);
}
}
};
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
ComboBoxBooleanModel comboBoxModel = new ComboBoxBooleanModel();
}
});
}
}

Here is a short demo of 2 JCombos, one of which will not change its background color when selected :
public static void main(String[] args){
JFrame frame = new JFrame("Combos BG Color test");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLocationRelativeTo(null);
frame.getContentPane().setPreferredSize(new Dimension(400, 40));
JPanel mainPanel = new JPanel();
mainPanel.setLayout(new GridLayout(1,2));
frame.add(mainPanel);
JComboBox<String> aCombo = new JComboBox<>(new String[]{"A","B","C"});
mainPanel.add(aCombo);
JComboBox<String> bCombo = new JComboBox<>(new String[]{"1","2","3"});
Color bgColor = bCombo.getBackground();
bCombo.setRenderer(new DefaultListCellRenderer() {
#Override
public void paint(Graphics g) {
setBackground(bgColor);
super.paint(g);
}
});
mainPanel.add(bCombo);
frame.pack();
frame.setVisible(true);
}
(Most of the credit goes to this answer)

How to add image in jlist

Hi i have created a j list and there i want to add an image before any text in that text how can i do this i tried but i am not able to achieve my goal i want to add an image before list element"Barmer".
public class ListDemo extends JPanel
implements ListSelectionListener {
private JList list;
private DefaultListModel listModel;
public ListDemo() {
super(new BorderLayout());
listModel = new DefaultListModel();
listModel.addElement("Barmer");
//Create the list and put it in a scroll pane.
list = new JList(listModel);
list.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
list.setSelectedIndex(0);
list.addListSelectionListener(this);
list.setVisibleRowCount(5);
list.setBackground(new java.awt.Color(0,191,255));;
list.setFont(new Font("Arial",Font.BOLD,35));
list.setForeground( Color.white );
list.setFixedCellHeight(60);
list.setFixedCellWidth(50);
list.setBorder(new EmptyBorder(10,20, 20, 20));
JScrollPane listScrollPane = new JScrollPane(list);
add(listScrollPane, BorderLayout.CENTER);
}
public void valueChanged(ListSelectionEvent e) {
}
private static void createAndShowGUI() {
//Create and set up the window.
JFrame frame = new JFrame("ListDemo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//Create and set up the content pane.
JComponent newContentPane = new ListDemo();
newContentPane.setOpaque(true); //content panes must be opaque
frame.setContentPane(newContentPane);
frame.setExtendedState(JFrame.MAXIMIZED_BOTH);
frame.setUndecorated(true);
//Display the window.
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
createAndShowGUI();
}
}
How can i do this help me?
Thanks in advance

You want to look as a custom ListCellRenderer. You can look at Provding a Custom Renderer for JComboBox. It the same for a JList. The tutorial over-complicates a bit for simple scenarios. They extends JLabel and implements ListCellRender where you have to implement a few unnecessary things if you just want basic functionality but with am image.
You can just instead extends or create a anonymous DefaultListCellRender and just get the JLabel render component and add to it, like setting Font and ImageIcon. Something like this
public class MarioListRenderer extends DefaultListCellRenderer {
Font font = new Font("helvitica", Font.BOLD, 24);
#Override
public Component getListCellRendererComponent(
JList list, Object value, int index,
boolean isSelected, boolean cellHasFocus) {
JLabel label = (JLabel) super.getListCellRendererComponent(
list, value, index, isSelected, cellHasFocus);
label.setIcon(imageMap.get((String) value));
label.setHorizontalTextPosition(JLabel.RIGHT);
label.setFont(font);
return label;
}
}
What happens is that each cell uses this renderer and calls the getListCellRendererComponent method. The value you see passed to the method is the value in each cell, in my case, one of the character names in the list. I then map that to the corresponding ImageIcon and set the Icon on the JLabel renderer component.
import java.awt.Component;
import java.awt.Dimension;
import java.awt.Font;
import java.util.HashMap;
import java.util.Map;
import javax.swing.DefaultListCellRenderer;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JList;
import javax.swing.JScrollPane;
import javax.swing.SwingUtilities;
public class MarioList {
private final Map<String, ImageIcon> imageMap;
public MarioList() {
String[] nameList = {"Mario", "Luigi", "Bowser", "Koopa", "Princess"};
imageMap = createImageMap(nameList);
JList list = new JList(nameList);
list.setCellRenderer(new MarioListRenderer());
JScrollPane scroll = new JScrollPane(list);
scroll.setPreferredSize(new Dimension(300, 400));
JFrame frame = new JFrame();
frame.add(scroll);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public class MarioListRenderer extends DefaultListCellRenderer {
Font font = new Font("helvitica", Font.BOLD, 24);
#Override
public Component getListCellRendererComponent(
JList list, Object value, int index,
boolean isSelected, boolean cellHasFocus) {
JLabel label = (JLabel) super.getListCellRendererComponent(
list, value, index, isSelected, cellHasFocus);
label.setIcon(imageMap.get((String) value));
label.setHorizontalTextPosition(JLabel.RIGHT);
label.setFont(font);
return label;
}
}
private Map<String, ImageIcon> createImageMap(String[] list) {
Map<String, ImageIcon> map = new HashMap<>();
for (String s : list) {
map.put(s, new ImageIcon(
getClass().getResource("/marioscaled/" + s + ".png")));
}
return map;
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
new MarioList();
}
});
}
}
Side Note
AndrewThompson is correct about just checking the tutorial first. You could have easily found an example implementation, then tried it out. Swing tutorials can be found here. Look under the Using Swing Components for how to use different components.
Swing apps should be run on the Event Dispatch Thread (EDT). You can do so by wrapping your creatAndShowGui() in a SwinUtilities.invokeLater.... See more at Initial Threads
UPDATE with internet images.
new Code
import java.awt.Component;
import java.awt.Dimension;
import java.awt.Font;
import java.net.URL;
import java.util.HashMap;
import java.util.Map;
import javax.swing.DefaultListCellRenderer;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JList;
import javax.swing.JScrollPane;
import javax.swing.SwingUtilities;
public class MarioList {
private final Map<String, ImageIcon> imageMap;
public MarioList() {
String[] nameList = {"Mario", "Luigi", "Bowser", "Koopa", "Princess"};
imageMap = createImageMap(nameList);
JList list = new JList(nameList);
list.setCellRenderer(new MarioListRenderer());
JScrollPane scroll = new JScrollPane(list);
scroll.setPreferredSize(new Dimension(300, 400));
JFrame frame = new JFrame();
frame.add(scroll);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public class MarioListRenderer extends DefaultListCellRenderer {
Font font = new Font("helvitica", Font.BOLD, 24);
#Override
public Component getListCellRendererComponent(
JList list, Object value, int index,
boolean isSelected, boolean cellHasFocus) {
JLabel label = (JLabel) super.getListCellRendererComponent(
list, value, index, isSelected, cellHasFocus);
label.setIcon(imageMap.get((String) value));
label.setHorizontalTextPosition(JLabel.RIGHT);
label.setFont(font);
return label;
}
}
private Map<String, ImageIcon> createImageMap(String[] list) {
Map<String, ImageIcon> map = new HashMap<>();
try {
map.put("Mario", new ImageIcon(new URL("http://i.stack.imgur.com/NCsHu.png")));
map.put("Luigi", new ImageIcon(new URL("http://i.stack.imgur.com/UvHN4.png")));
map.put("Bowser", new ImageIcon(new URL("http://i.stack.imgur.com/s89ON.png")));
map.put("Koopa", new ImageIcon(new URL("http://i.stack.imgur.com/QEK2o.png")));
map.put("Princess", new ImageIcon(new URL("http://i.stack.imgur.com/f4T4l.png")));
} catch (Exception ex) {
ex.printStackTrace();
}
return map;
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
new MarioList();
}
});
}
}