textview.java

mvc模式的示例代码。输入球的半径

import java.util.Observer;
import java.util.Observable;
import java.text.NumberFormat;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
/**
 *
 * <p>Title: The View part of Application </p>
 * <p>Description: A class can implement the Observer interface when it wants to
 *  be informed of changes in observable objects. </p>
 * <p>Copyright: Copyright (c) 2005</p>
 * @author Smart Lee
 * @version 1.1
 */
public class TextView extends JPanel implements Observer {
  GridBagLayout gridBagLayout1 = new GridBagLayout();
  private boolean textBlankFlag = true;
  JLabel radiusLab = new JLabel();
  JLabel volumeLab = new JLabel();
  JLabel suAreaLab = new JLabel();
  JTextField radiusTextField = new JTextField();
  JTextField volumeTextField = new JTextField();
  JTextField surfAreaTextField = new JTextField();

  public TextView() {
    try {
      jbInit();
    }
    catch(Exception e) {
      e.printStackTrace();
    }

  }
  //实现接口的方法
  public void update (Observable o, Object arg) {
    NumberFormat nf = NumberFormat.getInstance();
    Sphere balloon = (Sphere) o;
    if(textBlankFlag) {
      radiusTextField.setText("");
      volumeTextField.setText("");
      surfAreaTextField.setText("");
      textBlankFlag = false;
    }
    else {
      radiusTextField.setText(nf.format(balloon.getRadius()));
      volumeTextField.setText(nf.format(balloon.getVolume()));
      surfAreaTextField.setText(nf.format(balloon.getSuArea()));
    	
    }
  }
  private void jbInit() throws Exception {
    radiusLab.setFont(new java.awt.Font("Dialog", 0, 14));
    radiusLab.setText("  Radius =");
    this.setBackground(Color.lightGray);
    this.setForeground(Color.black);
    this.setLayout(gridBagLayout1);
    volumeLab.setFont(new java.awt.Font("Dialog", 0, 14));
    volumeLab.setText("  Volume =");
    suAreaLab.setFont(new java.awt.Font("Dialog", 0, 14));
    suAreaLab.setText("  Surface area =");
    radiusTextField.setFont(new java.awt.Font("Dialog", 0, 14));
    radiusTextField.setText("");
    volumeTextField.setFont(new java.awt.Font("Dialog", 0, 14));
    volumeTextField.setText("");
    surfAreaTextField.setFont(new java.awt.Font("Dialog", 0, 14));
//    surfAreaTextField.addActionListener(new TextView_surfAreaTextField_actionAdapter(this));
    this.add(radiusLab,     new GridBagConstraints(0, 0, 1, 2, 0.0, 0.0
            ,GridBagConstraints.NORTH, GridBagConstraints.NONE, new Insets(-1, 0, 0, 0), 86, 10));
    this.add(volumeLab,   new GridBagConstraints(0, 2, 1, 1, 0.0, 0.0
            ,GridBagConstraints.WEST, GridBagConstraints.NONE, new Insets(0, 0, 0, 0), 0, 0));
    this.add(suAreaLab,   new GridBagConstraints(0, 3, 1, 1, 0.0, 0.0
            ,GridBagConstraints.WEST, GridBagConstraints.NONE, new Insets(0, 0, 0, 0), 0, 0));
    this.add(radiusTextField,  new GridBagConstraints(1, 0, 1, 1, 0.0, 0.0
            ,GridBagConstraints.WEST, GridBagConstraints.NONE, new Insets(0, -19, 0, 19), 147, 1));
    this.add(volumeTextField, new GridBagConstraints(1, 1, 1, 2, 0.0, 0.0
            ,GridBagConstraints.WEST, GridBagConstraints.NONE, new Insets(0, -19, 0, 19), 147, 3));
    this.add(surfAreaTextField, new GridBagConstraints(1, 3, 1, 1, 0.0, 0.0
            ,GridBagConstraints.WEST, GridBagConstraints.NONE, new Insets(0, -19, 0, 19), 147, 4));
  }

  void surfAreaTextField_actionPerformed(ActionEvent e) {

  }

}
//class TextView_surfAreaTextField_actionAdapter implements java.awt.event.ActionListener {
//  TextView adaptee;
//
//  TextView_surfAreaTextField_actionAdapter(TextView adaptee) {
//    this.adaptee = adaptee;
//  }
//  public void actionPerformed(ActionEvent e) {
//    adaptee.surfAreaTextField_actionPerformed(e);
//  }
//}