fondo - color jcombobox java

Cambiar el color de fondo editable JComboBox

Question

Estoy programando un cuadro combinado editable en un Formulario JFrame, pero quiero cambiar el color de fondo.

Cómo funciona el programa: si hago clic en el botón "presionar", entonces el cuadro combinado de su fondo debe convertirse en negro.

Lo intenté:

1.

cbo.setBackground(Color.BLACK);

Pero no hizo nada

2

cbo.getEditor().getEditorComponent().setBackground(Color.BLACK);

((JTextField) cbo.getEditor().getEditorComponent()).setOpaque(true);

Haz esto:

Ejemplo de código:

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);
}

Estoy trabajando con Java JDK7

Alguna sugerencia?

Answer 1

ver mi ejemplo de código

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();
            }
        });
    }
}

Answer 2

Funciona para mí cambiar el color de un elemento seleccionado en 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);
    }

}

Si desea cambiar el color de los elementos en JCombobox a excepción de uno seleccionado, personalice ListCellRenderer.