在java中为特定单元格着色JTable

Question

我想通过输入行号和列号为JTable上的特定单元格着色。

例如，我有这样的代码，意味着颜色的第一单元行= 0，列= 0，但它不工作

package functions_classes; 

import java.awt.*; 
import java.awt.event.ActionEvent; 
import java.awt.event.ActionListener; 
import javax.swing.*; 
import javax.swing.border.LineBorder; 
import javax.swing.event.ListSelectionEvent; 
import javax.swing.event.ListSelectionListener; 
import javax.swing.table.*; 

public class RemoveAddRows extends JFrame { 

    static DefaultTableCellRenderer stringRenderer; 
    static Component c; 
    private static final long serialVersionUID = 1L; 
    private Object[] columnNames = {"Type", "Company", "Shares", "Price"}; 
    private Object[][] data = { 
     {"Buy", "IBM", Integer.valueOf(1000), Double.valueOf(80.50)}, 
     {"Sell", "MicroSoft", Integer.valueOf(2000), Double.valueOf(6.25)}, 
     {"Sell", "Apple", Integer.valueOf(3000), Double.valueOf(7.35)}, 
     {"Buy", "Nortel", Integer.valueOf(4000), Double.valueOf(20.00)} 
    }; 
    public static JTable table; 

    private DefaultTableModel model; 
    private javax.swing.Timer timer = null; 

    public RemoveAddRows() { 
     model = new DefaultTableModel(data, columnNames) { 
      private static final long serialVersionUID = 1L; 

      @Override 
      public Class getColumnClass(int column) { 
       return getValueAt(0, column).getClass(); 
      } 
     }; 

     table = new JTable(model) { 
      private static final long serialVersionUID = 1L; 

      @Override 
      public Component prepareRenderer(TableCellRenderer renderer, int row, int column) { 
       c = super.prepareRenderer(renderer, row, column);      
       System.out.println("la valeur de row egale "+row);      
       System.out.println("la valeur de column egale "+column); 
       if (isRowSelected(0) && isColumnSelected(0)) { 
        // ((JComponent) c).setBorder(new LineBorder(Color.red)); 
        ((JComponent) c).setBackground(Color.RED); 
        }      
       return c; 
      } 
     }; 

     stringRenderer = (DefaultTableCellRenderer) table.getDefaultRenderer(String.class); 
     stringRenderer.setHorizontalAlignment(SwingConstants.CENTER); 
     ListSelectionModel rowSelMod = table.getSelectionModel(); 

     rowSelMod.addListSelectionListener(new ListSelectionListener() { 
      @Override 
      public void valueChanged(ListSelectionEvent e) { 
       int row = table.getSelectedRow(); 
       int col = table.getSelectedColumn(); 
       String str = "Selected Row(s): "; 
       int[] rows = table.getSelectedRows(); 
       for (int i = 0; i < rows.length; i++) { 
        str += rows[i] + " "; 
       } 
       str += "Selected Column(s): "; 
       int[] cols = table.getSelectedColumns(); 
       for (int i = 0; i < cols.length; i++) { 
        str += cols[i] + " "; 
       } 
       str += "Selected Cell: " + table.getSelectedRow() + ", " + table.getSelectedColumn(); 
       System.out.println(str); 
       Object value = table.getValueAt(row, col); 
       System.out.println(String.valueOf(value)); 
      } 
     }); 
     table.setPreferredScrollableViewportSize(table.getPreferredSize()); 
     JScrollPane scrollPane = new JScrollPane(table); 
     add(scrollPane); 
     JButton button1 = new JButton("Remove all rows"); 
     button1.addActionListener(new ActionListener() { 
      @Override 
      public void actionPerformed(ActionEvent arg0) { 
       if (model.getRowCount() > 0) { 
        for (int i = model.getRowCount() - 1; i > -1; i--) { 
         model.removeRow(i); 
        } 
       } 
       System.out.println("model.getRowCount() --->" + model.getRowCount()); 
      } 
     }); 
     JButton button2 = new JButton("Add new rows"); 
     button2.addActionListener(new ActionListener() { 
      @Override 
      public void actionPerformed(ActionEvent arg0) { 
       start(); 
      } 
     }); 
     JPanel southPanel = new JPanel(); 
     southPanel.add(button1); 
     southPanel.add(button2); 
     add(southPanel, BorderLayout.SOUTH); 
    } 

    private void start() { 
     timer = new javax.swing.Timer(2500, updateCol()); 
     timer.start(); 
    } 

    public Action updateCol() { 
     return new AbstractAction("text load action") { 
      private static final long serialVersionUID = 1L; 

      @Override 
      public void actionPerformed(ActionEvent e) { 
       DefaultTableModel model = (DefaultTableModel) table.getModel(); 
       Object[] data0 = {"Buy", "IBM", Integer.valueOf(1000), Double.valueOf(80.50)}; 
       model.addRow(data0); 
       Object[] data1 = {"Sell", "MicroSoft", Integer.valueOf(2000), Double.valueOf(6.25)}; 
       model.addRow(data1); 
       Object[] data2 = {"Sell", "Apple", Integer.valueOf(3000), Double.valueOf(7.35)}; 
       model.addRow(data2); 
       Object[] data3 = {"Buy", "Nortel", Integer.valueOf(4000), Double.valueOf(20.00)}; 
       model.addRow(data3); 
       System.out.println("model.getRowCount() --->" + model.getRowCount()); 
       timer.stop(); 
       int rowIndex = table.getRowCount() - 1; 
       table.changeSelection(rowIndex, 0, false, false); 
      } 
     }; 
    } 

    public static void main(String[] args) { 
     javax.swing.SwingUtilities.invokeLater(new Runnable() { 
      @Override 
      public void run() { 
       RemoveAddRows frame = new RemoveAddRows(); 
       frame.setDefaultCloseOperation(EXIT_ON_CLOSE); 
       frame.pack(); 
       frame.setLocationRelativeTo(null); 
       frame.setVisible(true);      

      // table.prepareRenderer(stringRenderer, 1, 2); 
       //Component c1=table.prepareRenderer((DefaultTableCellRenderer) table.getDefaultRenderer(String.class), 1,1); 

       // stringRenderer = (DefaultTableCellRenderer) table.getDefaultRenderer(String.class); 
       // JComponent c1=(JComponent) table.prepareRenderer(stringRenderer, 0,0); 
       // c1.setBackground(Color.cyan); 
      } 
     }); 
    } 
} 

Answer 1

代替：

if (isRowSelected(0) && isColumnSelected(0)) { 
    // ((JComponent) c).setBorder(new LineBorder(Color.red)); 
    ((JComponent) c).setBackground(Color.RED); 
} 

使用此片的代码：

c.setBackground((row == 0) && (column == 0) ? Color.RED : Color.WHITE); 

Answer 2

JComponent不知道如何设置它的背景。相反，您应该手动在组件上绘制颜色。

我建议你创建自己的组件：

private class CustomComponent extends JComponent{ 
    CustomComponent() { 
      setBackground(Color.BLACK); 
    } 
    public void paintComponent(Graphics g) { 
      g.setColor(getBackground()); 
      g.fillRect(0, 0, getWidth(), getHeight()); 
    } 

}

你可以做isSelected验证您的自定义组件内，并设置相应的颜色。

Answer 3

你将需要实现一个自定义的单元格渲染器来完成这个工作，我已经修改了我的一些旧代码。希望这应该工作，我已检查它编译，但我没有测试它;

import javax.swing.JTable; 
import javax.swing.table.DefaultTableCellRenderer; 
import java.awt.Component; 
import java.awt.Color; 
import java.util.HashMap; 

public class ColorCellRenderer extends DefaultTableCellRenderer { 
    class Coordinate 
    { 
     public int row, col; 
     public Coordinate(int row, int col) 
     { 
      this.row=row;this.col=col; 
     } 
     @Override 
     public boolean equals(Object o) 
     { 
      if(o instanceof Coordinate) 
      { 
       return (((Coordinate)o).row==this.row)&&(((Coordinate)o).col==this.col); 
      } 
      return false; 
     } 
     @Override 
     public int hashCode() 
     {//Unique until col 10000 
      return col + row*10000; 
     } 
    } 
    private HashMap<Coordinate, Color> colorMap; 
    public ColorCellRenderer() { 
     super(); 
     colorMap = new HashMap<Coordinate, Color>(); 
    } 
    public Color setColor(int row, int col, Color c) 
    { 
     return colorMap.put(new Coordinate(row, col), c); 
    } 
    /** 
    * Returns the component used for drawing the cell. This method is 
    * used to configure the renderer appropriately before drawing. 
    * 
    * @param table  - JTable object 
    * @param value  - the value of the cell to be rendered. 
    * @param isSelected - isSelected true if the cell is to be rendered with the selection highlighted; 
    *     otherwise false. 
    * @param hasFocus - if true, render cell appropriately. 
    * @param row  - The row index of the cell being drawn. 
    * @param column  - The column index of the cell being drawn. 
    * @return - Returns the component used for drawing the cell. 
    */ 

    public Component getTableCellRendererComponent 
    (
     JTable table, 
     Object value, 
     boolean isSelected, 
     boolean hasFocus, 
     int row, 
     int column 
    ) 
     { 
      Component c = super.getTableCellRendererComponent(table, value, isSelected, hasFocus, row, column); 
      //Get color from nested hashmap 
      //We allow it to setBackground(null) as DefaultRenderer doesn't resetBackground when called again. 
       if(isSelected){ 
        c.setBackgroun(table.getSelectionBackground()); 
       }else{ 
        c.setBackground(colorMap.get(new Coordinate(row, column))); 
      } 
       return c; 
     } 
}