java - 定时器执行错误

Question

我的计时器出现错误，并且我不知道错误在代码中的位置。

错误:

Exception in thread "main" java.lang.Error: Unresolved compilation problems: The constructor Timer(int, Player) is undefined The method start() is undefined for the type Timer

at Player.(Player.java:12)

at Game.main(Game.java:11)

import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.geom.Ellipse2D;
import java.util.Timer;

import javax.swing.*;


public class Player extends JPanel implements ActionListener{
Timer t = new Timer(5, this); // Error (LINE 12)
double x = 0; double velX = 2;
double y = 0; double velY = 2;

public void paintComponent(Graphics g){
    super.paintComponent(g);
    Graphics2D g2 = (Graphics2D) g;
    Ellipse2D circle = new Ellipse2D.Double(x,y,40,40);
    g2.fill(circle);
    t.start(); // error
}

public void actionPerformed(ActionEvent e){
    x += velX;
    y += velY;
    repaint();
  }
}

Answer 1

您已导入java.util.Timer。也许您的意思是javax.swing.Timer？

您可以通过谷歌搜索了解更多信息，但是here很好地解释了两者之间的差异。