我得到的java:105:错误:非法字符:\ 29 }为什么我得到{error?
我写一个程序,用户可以点击左/右/上/下按钮,移动“球”在屏幕上。
我搞不清楚我做错了什么。有人可以帮助我吗?
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class Lab2a extends JFrame {
Lab2a(){
setTitle("Lab 1b - Application #2");
Lab2Panel p = new Lab2Panel();
add(p);
}
public static void main(String[] args){
Lab2 frame = new Lab2();
frame.setTitle("Lab2 Application # 1");
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(600, 400);
frame.setVisible(true);
}
}
class Lab2Panel extends JPanel{
Lab2Button canvas = new Lab2Button();
JPanel panel = new JPanel();
Lab2Panel() {
setLayout(new BorderLayout());
JButton leftButton = new JButton("left");
JButton rightButton = new JButton("right");
JButton upButton = new JButton("up");
JButton downButton = new JButton("down");
panel.add(leftButton);
panel.add(rightButton);
panel.add(upButton);
panel.add(downButton);
this.add(canvas, BorderLayout.CENTER);
this.add(panel, BorderLayout.SOUTH);
leftButton.addActionListener(new LeftListener(canvas));
rightButton.addActionListener(new RightListener(canvas));
upButton.addActionListener(new UpListener(canvas));
downButton.addActionListener(new DownListener(canvas));
}
}
class Lab2Button extends JPanel {
int radius = 5;
int x = -1;
int y = -1;
protected void paintComponent(Graphics g){
if (x<0 || y<0) {
x = getWidth()/2 - radius;
y = getHeight()/2 - radius;
}
super.paintComponent(g);
g.drawOval(x,y, 2 * radius, 2 * radius);
}
public void moveLeft(){
x -= 5;
this.repaint();
}
public void moveRight(){
x += 5;
this.repaint();
}
public void moveUp(){
y += 5;
this.repaint();
}
public void moveDown(){
y -= 5;
this.repaint();
}
}
class LeftListener implements ActionListener{
private Lab2Button canvas;
LeftListener(Lab2Button canvas) {
this.canvas = canvas;
}
public void actionPerformed(ActionEvent e){
canvas.moveLeft();
}
}
对不起,关于105是这一条上面的线。
class RightListener implements ActionListener{
private Lab2Button canvas;
RightListener(Lab2Button canvas) {
this.canvas = canvas;
}
public void actionPerformed(ActionEvent e){
canvas.moveRight();
}
}
class UpListener implements ActionListener{
private Lab2Button canvas;
UpListener(Lab2Button canvas) {
this.canvas = canvas;
}
public void actionPerformed(ActionEvent e){
canvas.moveUp();
}
}
class DownListener implements ActionListener{
private Lab2Button canvas;
DownListener(Lab2Button canvas) {
this.canvas = canvas;
}
public void actionPerformed(ActionEvent e){
canvas.moveDown();
}
}
你能告诉我们哪一行是105行吗? – ggreiner 2012-02-06 18:39:23
哪一行是105行? – templatetypedef 2012-02-06 18:39:32
仔细阅读错误信息,尝试理解它,并仔细缩进代码。 – 2012-02-06 18:44:02