mylistcellrenderer.java

java程序设计导论（daniel liang著） 所有偶数课后习题答案

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

public class MyListCellRenderer implements ListCellRenderer {
  JPanel listCellPanel = new JPanel();
  ImageViewer imageViewer = new ImageViewer();
  JLabel jlbl = new JLabel(" ", JLabel.LEFT);
  Border lineBorder =
    BorderFactory.createLineBorder(Color.black, 1);
  Border emptyBorder =
    BorderFactory.createEmptyBorder(2, 2, 2, 2);

  public MyListCellRenderer() {
    listCellPanel.setOpaque(true);
    jlbl.setPreferredSize(new Dimension(100, 60));
    listCellPanel.setLayout(new BorderLayout(10, 5));
    listCellPanel.add(imageViewer, BorderLayout.CENTER);
    listCellPanel.add(jlbl, BorderLayout.EAST);
  }

  /** Implement this method in ListCellRenderer */
  public Component getListCellRendererComponent
    (JList list, Object value, int index, boolean isSelected,
      boolean cellHasFocus) {
    Object[] pair = (Object[])value; // Cast value into an array
    imageViewer.setImage((Image)pair[0]);
    jlbl.setText(pair[1].toString());

    if (isSelected) {
      listCellPanel.setForeground(list.getSelectionForeground());
      listCellPanel.setBackground(list.getSelectionBackground());
    }
    else {
      listCellPanel.setForeground(list.getForeground());
      listCellPanel.setBackground(list.getBackground());
    }

    listCellPanel.setBorder(cellHasFocus ? lineBorder : emptyBorder);

    return listCellPanel;
  }
}