如何突出显示JTable中的特定列标题

Question

我需要突出显示JTable中的特定列标题。是否可以这样做？ 也有可能在JTable中绘制垂直线吗？

Answer 1

两者都是可能的。例如：

public class Test extends JPanel{ 

private JTable table; 
private String COLUMN1 = "COLUMN1"; 
private String COLUMN2 = "COLUMN2"; 

public Test() { 
    setLayout(new BorderLayout()); 
    table = new LineTable(new Object[][]{{"1", "2"}, {"3", "4"}}, new Object[]{COLUMN1, COLUMN2}); 

    TableColumn col = table.getColumn(COLUMN1); 
    col.setIdentifier(COLUMN1); 
    col.setHeaderValue("Column1"); 

    col = table.getColumn(COLUMN2); 
    col.setIdentifier(COLUMN2); 
    col.setHeaderValue(new ColorHeaderValue("Column2")); 
    col.setHeaderRenderer(new ColorHeaderRenderer()); 
    col.setCellRenderer(new LineCellRenderer()); 

    JPanel pn = new JPanel(); 
    pn.setLayout(new BoxLayout(pn, BoxLayout.X_AXIS)); 

    pn.add(new JButton(new AbstractAction("Highlight Column2 in red"){ 

     @Override 
     public void actionPerformed(ActionEvent e){ 
      setColumnColor(COLUMN2, Color.RED); 
     } 
    })); 
    pn.add(new JButton(new AbstractAction("Clear Column2 header color"){ 

     @Override 
     public void actionPerformed(ActionEvent e){ 
      setColumnColor(COLUMN2, null); 
     } 
    })); 
    pn.add(Box.createHorizontalGlue()); 
    add(pn, BorderLayout.NORTH); 
    add(new JScrollPane(table), BorderLayout.CENTER); 
} 

private void setColumnColor(final String columnID, final Color cl){ 
    SwingUtilities.invokeLater(new Runnable(){ 

     @Override 
     public void run(){ 
      Object headerValue = table.getColumn(columnID).getHeaderValue(); 
      if(headerValue instanceof ColorHeaderValue){ 
       ColorHeaderValue clHeaderValue = (ColorHeaderValue) headerValue; 
       clHeaderValue.setBrgColor(cl); 
       table.getTableHeader().repaint(); 
      } 
     } 
    }); 

} 

private static class LineTable extends JTable{ 

    public LineTable(Object[][] rowData, Object[] columnNames) { 
     super(rowData, columnNames); 

    } 

    protected void paintComponent(Graphics g){ 
     super.paintComponent(g); 
     if (g != null){ 
      g.drawLine(0, 0, this.getWidth(), getHeight()); 
     } 

    } 
} 
private static class LineCellRenderer extends DefaultTableCellRenderer{ 

    @Override 
    protected void paintComponent(Graphics g){    
     super.paintComponent(g); 
     if (g != null){ 
      int halfX = getWidth()/2; 
      g.drawLine(halfX, 0, halfX, getHeight()); 
     } 
    } 

} 
private static class ColorHeaderRenderer extends DefaultTableCellHeaderRenderer{ 

    @Override 
    public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected, boolean hasFocus, int row, int column){ 
     Component res = super.getTableCellRendererComponent(table, value, isSelected, hasFocus, row, column); 
     if (value instanceof ColorHeaderValue){ 
      ColorHeaderValue headerValue = (ColorHeaderValue) value; 
      if (headerValue.getBrgColor() != null){ 
       setBackground(headerValue.getBrgColor()); 
      } 
     } 
     return res; 
    } 

} 
private static class ColorHeaderValue{ 

    private Color brgColor; 
    private String title; 

    public ColorHeaderValue(String title) { 
     this.title = title; 
    } 

    public final Color getBrgColor(){ 
     return brgColor; 
    } 

    public final void setBrgColor(Color brgColor){ 
     this.brgColor = brgColor; 
    } 

    public String toString(){ 
     return title; 
    } 

} 

public static void main(String[] args){ 
    JFrame frame = new JFrame("test"); 
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 

    // Add content to the window. 
    frame.add(new Test()); 

    // Display the window. 
    frame.pack(); 
    frame.setSize(300, 200); 
    frame.setVisible(true); 
}}