Question

我尝试过以下代码。请指导我哪里错了???期望的输出就像...... 米（延迟）E（延迟）S（延迟）S（延迟）一（延迟）克（延迟）即

import java.util.*;    
import java.applet.*;    
import java.awt.*;    

/*<applet code="MessageWithDelay" width=400 height=200>
</applet>*/

public class MessageWithDelay extends Applet implements Runnable {
Thread t;
//char msg[] ={"m","e","s","s","a","g","e"};
String str = "message";
Graphics bufferg;
Image buffer;
int counter=0,x=str.length(),i=0;;

    public void init() {

            //initializa the thread
            t = new Thread(this);
            t.start();

            Dimension d = getSize();
            buffer = createImage(d.width,d.height);

            }

    public void run() {

        try {
            while(true)
            {
            //requesting repaint
            repaint();
            if(counter==x)
            {
                    Thread.sleep(200);
                    counter=0;
                    i=0;
            }
            else
            {
                    Thread.sleep(400);
            }
            }
            }
         catch(Exception e) {
         }
            }

    public void update(Graphics g) {
    paint(g);
    }

    public void paint(Graphics g) {

      if(bufferg == null) {

      Dimension d = getSize();
      bufferg.setColor(Color.green);

            g.setFont(new Font("Comic Sans MS",Font.BOLD,36));


            bufferg.drawString(str.charAt(i)+"",20,20);
            counter++;
            i+=1;
       //update screen
       g.drawImage(buffer,0,0,this);




       }
   }

}

我正在处理命令提示符，它给了我一堆不同的错误。我想知道为什么如果有人能通过尝试解释我的错误。提前完成。

Answer 1

我发现的问题包括：

使用JApplet而不是Applet。
在init方法中，在启动线程之前创建缓冲区。
使用run方法中的字母更新缓冲区。油漆方法只是油漆。没有计算。

这是工作代码。我将代码格式化为Eclipse，这是一个用于Java开发的集成开发环境（IDE）。

import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Image;

import javax.swing.JApplet;

/*<applet code="MessageWithDelay" width=400 height=200>
 </applet>*/

public class MessageWithDelay extends JApplet implements Runnable {
    private static final long   serialVersionUID    = 1722008447683646619L;

    Thread      t;
    String      str = "message";
    Image       buffer;

    @Override
    public void init() {

        Dimension d = getSize();
        buffer = createImage(d.width, d.height);

        // Initialize the thread
        t = new Thread(this);
        t.start();

    }

    @Override
    public void run() {
        int x = 40;
        int y = 40;
        for (int i = 0; i < str.length(); i++) {
            Graphics g = buffer.getGraphics();
            g.setFont(new Font("Comic Sans MS", Font.BOLD, 36));
            g.setColor(Color.GREEN);
            g.drawString("" + str.charAt(i), x, y);
            g.dispose();
            x += 40;
            repaint();
            try {
                Thread.sleep(1000L);
            } catch (InterruptedException e) {
            }
        }

    }

    @Override
    public void update(Graphics g) {
        paint(g);
    }

    @Override
    public void paint(Graphics g) {
        g.drawImage(buffer, 0, 0, this);
    }

}

尝试逐字符打印字符串，并在两个字符打印之间延迟

1 个答案: