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Java高级教程:事件处理

作者:互联网

Applet类从Container类继承了许多事件处理方法。Container类定义了几个方法,例如:processKeyEvent()和processMouseEvent(),用来处理特别类型的事件,还有一个捕获所有事件的方法叫做processEvent。

 

  为了响应一个事件,applet必须重写合适的事件处理方法。

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import java.awt.event.MouseListener;

import java.awt.event.MouseEvent;

import java.applet.Applet;

import java.awt.Graphics;

   

public class ExampleEventHandling extends Applet

                             implements MouseListener {

   

    StringBuffer strBuffer;

   

    public void init() {

         addMouseListener(this);

         strBuffer = new StringBuffer();

        addItem("initializing the apple ");

    }

   

    public void start() {

        addItem("starting the applet ");

    }

   

    public void stop() {

        addItem("stopping the applet ");

    }

   

    public void destroy() {

        addItem("unloading the applet");

    }

   

    void addItem(String word) {

        System.out.println(word);

        strBuffer.append(word);

        repaint();

    }

   

    public void paint(Graphics g) {

         //Draw a Rectangle around the applet's display area.

        g.drawRect(0, 0,

                      getWidth() - 1,

                      getHeight() - 1);

   

         //display the string inside the rectangle.

        g.drawString(strBuffer.toString(), 10, 20);

    }

   

    

    public void mouseEntered(MouseEvent event) {

    }

    public void mouseExited(MouseEvent event) {

    }

    public void mousePressed(MouseEvent event) {

    }

    public void mouseReleased(MouseEvent event) {

    }

   

    public void mouseClicked(MouseEvent event) {

         addItem("mouse clicked! ");

    }

}

标签:事件处理,教程,Java,MouseEvent,void,addItem,public,applet,event
来源: https://www.cnblogs.com/gjdftru/p/12382624.html