不可编辑的JComboBox边框

Question

I am using Metal L&F. I want to make a , that has only 1 pixel border. This not a problem, as long as the cb is . This corresponds to the first cb in the picture named "Editable".

cb.setEditable(true);
((JTextComponent) (cb.getEditor().getEditorComponent())).setBorder(BorderFactory.createMatteBorder(1, 1, 1, 0, COLOR));

But when I do , an additional border occurs inside the box (changed to red in the picture "Dropdown", you see the original color in the picture named "Fixed"). Although I tried to set the border and I also tried to use my own CellRenderer, the border still gets painted. It seems to me, that the unwanted border does not come from the CellRenderer. When I try to manipulate the border from the cb itself (see comment //), it only adds/removes an additional outer border. The editorComponent also seems not to be responsible to me.

cb.setRenderer(new CbCellRenderer());
//cb.setBorder(BorderFactory.createMatteBorder(1, 1, 1, 1, COLOR));
//cb.setBorder(BorderFactory.createEmptyBorder());

class CbCellRenderer implements ListCellRenderer {

    protected DefaultListCellRenderer defaultRenderer = new DefaultListCellRenderer();

    @Override
    public Component getListCellRendererComponent(JList list, Object value, int index, boolean isSelected, boolean cellHasFocus) {
        JLabel renderer = (JLabel) defaultRenderer.getListCellRendererComponent(list, value, index, isSelected, cellHasFocus);
        renderer.setBorder(BorderFactory.createEmptyBorder());
        return renderer;
    }        
}

I also tried out some UI variables like the ones below without taking affect on this border.

UIManager.setLookAndFeel("javax.swing.plaf.metal.MetalLookAndFeel");
UIManager.put("ComboBox.selectionForeground", Color.green);
UIManager.put("ComboBox.disabledBackground", Color.green);
...

Image: http://upload.mtmayr.com/dropdown_frame.png ^{(link broken)}

Complete code for testing:

import java.awt.*;
import java.util.Vector;
import javax.swing.*;
import javax.swing.plaf.basic.BasicComboPopup;

public class ComboTest {

    private Vector<String> listSomeString = new Vector<String>();
    private JComboBox editableComboBox = new JComboBox(listSomeString);
    private JComboBox nonEditableComboBox = new JComboBox(listSomeString);
    private JFrame frame;
    public final static Color COLOR_BORDER = new Color(122, 138, 153);

    public ComboTest() {
        listSomeString.add("row 1");
        listSomeString.add("row 2");
        listSomeString.add("row 3");
        listSomeString.add("row 4");

        editableComboBox.setEditable(true);
        editableComboBox.setBackground(Color.white);
        Object child = editableComboBox.getAccessibleContext().getAccessibleChild(0);
        BasicComboPopup popup = (BasicComboPopup) child;
        JList list = popup.getList();
        list.setBackground(Color.white);
        list.setSelectionBackground(Color.red);
        JTextField tf = ((JTextField) editableComboBox.getEditor().getEditorComponent());
        tf.setBorder(BorderFactory.createMatteBorder(1, 1, 1, 0, COLOR_BORDER));

        nonEditableComboBox.setEditable(false);
        nonEditableComboBox.setBorder(BorderFactory.createEmptyBorder());
        nonEditableComboBox.setBackground(Color.white);
        Object childNonEditable = nonEditableComboBox.getAccessibleContext().getAccessibleChild(0);
        BasicComboPopup popupNonEditable = (BasicComboPopup) childNonEditable;
        JList listNonEditable = popupNonEditable.getList();
        listNonEditable.setBackground(Color.white);
        listNonEditable.setSelectionBackground(Color.red);

        frame = new JFrame();
        frame.setLayout(new GridLayout(0, 1, 10, 10));
        frame.add(editableComboBox);
        frame.add(nonEditableComboBox);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setLocation(100, 100);
        frame.pack();
        frame.setVisible(true);
    }

    public static void main(String[] args) {

        SwingUtilities.invokeLater(new Runnable() {

            @Override
            public void run() {
                ComboTest ct = new ComboTest();
            }
        });
    }
}

Answer 1

• not able to ...., every have got the same Borders, there must be another issue, 1st and 2nd. are editable JComboBoxes

• for better help sooner post an SSCCE, short, runnable, compilable, just about two JComboBoxes, Native OS, compiled in JDK, runned in JRE

WinXP Java6

Win7 Java7

Win7 Java6

Win8 Java6

Win8 Java7

from code

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++) {
            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

• How about override MetalComboBoxUI#paintCurrentValueBackground(...)
  • using JDK 1.7.0_17, Windows 7

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.text.*;
import javax.swing.plaf.*;
import javax.swing.plaf.basic.*;
import javax.swing.plaf.metal.*;

public class ComboBoxUIDemo {
  private static Color BORDER = Color.GRAY;
  public JComponent makeUI() {
    //UIManager.put("ComboBox.foreground", Color.WHITE);
    //UIManager.put("ComboBox.background", Color.BLACK);
    //UIManager.put("ComboBox.selectionForeground", Color.CYAN);
    //UIManager.put("ComboBox.selectionBackground", Color.BLACK);

    //UIManager.put("ComboBox.buttonDarkShadow", Color.WHITE);
    //UIManager.put("ComboBox.buttonBackground", Color.GRAY);
    //UIManager.put("ComboBox.buttonHighlight", Color.WHITE);
    //UIManager.put("ComboBox.buttonShadow", Color.WHITE);
    //UIManager.put("ComboBox.editorBorder", BorderFactory.createLineBorder(Color.RED));

    Box box = Box.createVerticalBox();

    UIManager.put("ComboBox.border", BorderFactory.createEmptyBorder());
    for(int i=0; i<2; i++) { // Defalut
      JComboBox<String> cb = new JComboBox<>(makeModel());
      if(i%2==0) setEditable(cb);
      setPopupBorder(cb);
      box.add(cb);
      box.add(Box.createVerticalStrut(10));
    }

    {
      // Override MetalComboBoxUI#paintCurrentValueBackground(...)
      JComboBox<String> cb = new JComboBox<>(makeModel());
      cb.setUI(new MetalComboBoxUI() {
        @Override public void paintCurrentValueBackground(
        Graphics g, Rectangle bounds, boolean hasFocus) {
          //if (MetalLookAndFeel.usingOcean()) {
          if(MetalLookAndFeel.getCurrentTheme() instanceof OceanTheme) {
            g.setColor(MetalLookAndFeel.getControlDarkShadow());
            g.drawRect(bounds.x, bounds.y, bounds.width, bounds.height - 1);
            //COMMENTOUT>>>
            //g.setColor(MetalLookAndFeel.getControlShadow());
            //g.drawRect(bounds.x + 1, bounds.y + 1, bounds.width - 2,
            //           bounds.height - 3);
            //<<<COMMENTOUT
            if (hasFocus && !isPopupVisible(comboBox) && arrowButton != null) {
              g.setColor(listBox.getSelectionBackground());
              Insets buttonInsets = arrowButton.getInsets();
              if (buttonInsets.top > 2) {
                g.fillRect(bounds.x + 2, bounds.y + 2, bounds.width - 3,
                           buttonInsets.top - 2);
              }
              if (buttonInsets.bottom > 2) {
                g.fillRect(bounds.x + 2, bounds.y + bounds.height -
                           buttonInsets.bottom, bounds.width - 3,
                           buttonInsets.bottom - 2);
              }
            }
          } else if (g == null || bounds == null) {
            throw new NullPointerException(
              "Must supply a non-null Graphics and Rectangle");
          }
        }
      });
      setPopupBorder(cb);

      box.add(cb);
      box.add(Box.createVerticalStrut(10));
    }

    UIManager.put("ComboBox.border", BorderFactory.createLineBorder(BORDER));
    for(int i=0; i<2; i++) { // BasicComboBoxUI
      JComboBox<String> cb = new JComboBox<>(makeModel());
      if(i%2==0) setEditable(cb);
      cb.setUI(new BasicComboBoxUI());
      setPopupBorder(cb);
      box.add(cb);
      box.add(Box.createVerticalStrut(10));
    }

    JPanel p = new JPanel(new BorderLayout());
    p.setBorder(BorderFactory.createEmptyBorder(10,20,10,20));
    p.add(box, BorderLayout.NORTH);
    return p;
  }
  private static void setEditable(JComboBox cb) {
    cb.setEditable(true);
    ComboBoxEditor editor = cb.getEditor();
    Component c = editor.getEditorComponent();
    if(c instanceof JTextField) {
      JTextField tf = (JTextField)c;
      tf.setBorder(BorderFactory.createMatteBorder(1,1,1,0,BORDER));
    }
  }
  private static void setPopupBorder(JComboBox cb) {
    Object o = cb.getAccessibleContext().getAccessibleChild(0);
    JComponent c = (JComponent)o;
    c.setBorder(BorderFactory.createMatteBorder(0,1,1,1,BORDER));
  }
  private static DefaultComboBoxModel<String> makeModel() {
    DefaultComboBoxModel<String> m = new DefaultComboBoxModel<>();
    m.addElement("1234");
    m.addElement("5555555555555555555555");
    m.addElement("6789000000000");
    return m;
  }
  public static void main(String[] args) {
//     OceanTheme theme = new OceanTheme() {
//       @Override protected ColorUIResource getSecondary2() {
//         return new ColorUIResource(Color.RED);
//       }
//     };
//     MetalLookAndFeel.setCurrentTheme(theme);

    EventQueue.invokeLater(new Runnable() {
      @Override public void run() {
        createAndShowGUI();
      }
    });
  }
  public static void createAndShowGUI() {
    JFrame f = new JFrame();
    f.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
    f.getContentPane().add(new ComboBoxUIDemo().makeUI());
    f.setSize(320, 240);
    f.setLocationRelativeTo(null);
    f.setVisible(true);
  }
}