java-不可编辑的JComboBox边框
作者：互联网
我正在使用Metal L& F.我想制作一个JComboBox,它只有1个像素边框.只要cb是可编辑的,这不是问题.这对应于图片中名为“可编辑”的第一个cb.
cb.setEditable(true);
((JTextComponent) (cb.getEditor().getEditorComponent())).setBorder(BorderFactory.createMatteBorder(1, 1, 1, 0, COLOR));
但是,当我执行cb.setEditable(false)时,框内会出现一个额外的边框(在图片“ Dropdown”中变为红色,您会在图片中看到“ Fixed”的原始颜色).尽管我尝试设置边框,也尝试使用自己的CellRenderer,但边框仍然被绘制.在我看来,不需要的边框不是来自CellRenderer.当我尝试从cb本身操纵边框时(请参阅注释//),它只会添加/删除其他外部边框. editorComponent似乎也不对我负责.
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;
}
}
我还尝试了一些如下所示的UI变量,但不影响此边界.
UIManager.setLookAndFeel("javax.swing.plaf.metal.MetalLookAndFeel");
UIManager.put("ComboBox.selectionForeground", Color.green);
UIManager.put("ComboBox.disabledBackground", Color.green);
...
图片：http://upload.mtmayr.com/dropdown_frame.png(链接断开)
完整的测试代码：
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();
}
});
}
}
解决方法:
>如何覆盖MetalComboBoxUI#paintCurrentValueBackground(…)
>在Windows 7中使用JDK 1.7.0_17
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);
}
}
标签：jcombobox,border,swing,java 来源： https://codeday.me/bug/20191031/1973071.html