mypanel.java~42~

很好得jbuilder100例源代码

package drawline;

import java.awt.*;
import javax.swing.JPanel;
import java.awt.event.*;

/**
 * Title:
 * Description:
 * Copyright:    Copyright (c) 2001
 * Company:
 * @author
 * @version 1.0
 */

public class MyPanel extends JPanel {
  BorderLayout borderLayout1 = new BorderLayout();
  Label label1 = new Label();
  Point p = null;
  Panel panel1 = new Panel();
  Button button1 = new Button();
  Button button2 = new Button();


  public MyPanel() {
    try {
      jbInit();
    }
    catch(Exception ex) {
      ex.printStackTrace();
    }
  }
  void jbInit() throws Exception {
    this.addMouseMotionListener(new java.awt.event.MouseMotionAdapter() {
      public void mouseMoved(MouseEvent e) {
        this_mouseMoved(e);
      }
    });
    this.setLayout(borderLayout1);
    this.addMouseListener(new java.awt.event.MouseAdapter() {
      public void mouseClicked(MouseEvent e) {
        this_mouseClicked(e);
      }
    });
    button1.setLabel("New Line");
    button1.addActionListener(new java.awt.event.ActionListener() {
      public void actionPerformed(ActionEvent e) {
        button1_actionPerformed(e);
      }
    });
    button2.setLabel("Clear All");
    button2.addActionListener(new java.awt.event.ActionListener() {
      public void actionPerformed(ActionEvent e) {
        button2_actionPerformed(e);
      }
    });
    this.add(label1, BorderLayout.SOUTH);
    this.add(panel1, BorderLayout.NORTH);
    panel1.add(button1, null);
    panel1.add(button2, null);
  }

/*  public void paintComponent(Graphics g){
    super.paintComponent(g);
    //g.setColor(Color.red);
    //g.drawLine(1,1,23,20);
    //g.drawLine(10,10,90,90);
  }*/

  void this_mouseMoved(MouseEvent e) {
    String s = "("+String.valueOf(e.getX())+","+String.valueOf(e.getY())+")";
    if (p != null)
      s = "Line To:" + s;
    label1.setText(s);
  }

  void this_mouseClicked(MouseEvent e) {
    Graphics g = this.getGraphics();
    g.setColor(Color.red);
    if (p != null)
      g.drawLine(e.getX(),e.getY(),(int)p.getX(),(int)p.getY());
    p = new Point(e.getX(),e.getY());
  }

  void button2_actionPerformed(ActionEvent e) {
    Graphics g = this.getGraphics();
    g.clearRect(0,0,this.getWidth(),this.getHeight());
    p = null;
  }

  void button1_actionPerformed(ActionEvent e) {
    p = null;
  }


}