java - 如何在java中使用DefaultTableCellRenderer将图像插入到列表中

Question

我编写此代码用于将图像插入到列中

LessonTable.setDefaultRenderer(Object.class, new SimpleTableCellRenderer());

class SimpleTableCellRenderer extends DefaultTableCellRenderer {

      ImageIcon image = new ImageIcon(getClass().getResource("imagefolder/this.png"));
      JLabel lbl = new JLabel();

     @Override
     public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected, boolean hasFocus, int row, int column) {

            lbl = (JLabel) super.getTableCellRendererComponent(table, value, isSelected, hasFocus, row, column);

           if (column == 1) {// i want to set image only for this column
               lbl.setHorizontalAlignment(SwingConstants.LEFT);
               lbl.setIcon(image);
            } 
           else {
              lbl.setHorizontalAlignment(SwingConstants.CENTER);
            }

      return lbl;

    }
 }

但是此代码会为除第二列之外的所有列插入图像。这里出了什么问题？

Answer 1

不要创建自定义渲染器。 JTable 已经支持图标渲染器。

相反，您需要做的是重写表模型的 getColumnClass(...) 方法以返回 Icon.class 并且表将使用正确的渲染器.

import java.awt.*;
import javax.swing.*;
import javax.swing.table.*;

public class TableIcon extends JPanel
{
    public TableIcon()
    {
        Icon aboutIcon = new ImageIcon("about16.gif");
        Icon addIcon = new ImageIcon("add16.gif");
        Icon copyIcon = new ImageIcon("copy16.gif");

        String[] columnNames = {"Picture", "Description"};
        Object[][] data =
        {
            {aboutIcon, "About"},
            {addIcon, "Add"},
            {copyIcon, "Copy"},
        };

        DefaultTableModel model = new DefaultTableModel(data, columnNames)
        {
            //  Returning the Class of each column will allow different
            //  renderers to be used based on Class
            public Class getColumnClass(int column)
            {
                return getValueAt(0, column).getClass();
            }
        };
        JTable table = new JTable( model );
        table.setPreferredScrollableViewportSize(table.getPreferredSize());

        JScrollPane scrollPane = new JScrollPane( table );
        add( scrollPane );
    }

    private static void createAndShowGUI()
    {
        JFrame frame = new JFrame("Table Icon");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.add(new TableIcon());
        frame.setLocationByPlatform( true );
        frame.pack();
        frame.setVisible( true );
    }

    public static void main(String[] args)
    {
        EventQueue.invokeLater(new Runnable()
        {
            public void run()
            {
                createAndShowGUI();
            }
        });
    }

}