我正在尝试实现单击和拖动方法，为此我需要 mousePressed 和 mouseReleased 事件。我还将使用 mouseClicked 事件，因此我实现了 MouseMotionListener 和 MouseListener。
但是，当我编写 mousePressed、mouseReleased、mouseEntered、mouseExited 方法时，出现以下错误：
method mousePressed(MouseEvent) is already defined in class BoingPanel
这是整个班级：
import java.awt.Color;
import java.awt.Graphics;
import java.awt.event.ActionEvent;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.MouseMotionListener;
import java.util.ArrayList;
import javax.swing.JPanel;
public class BoingPanel extends JPanel implements MouseMotionListener, MouseListener {
private int width;
private int height;
private int updateRate=40;
ArrayList<Ball> balls;
ArrayList<Line> lines;
private Container box;
private boolean drag = false;
public void mouseEntered(MouseEvent e) { }
public void mouseExited(MouseEvent e) { }
public void mousePressed(MouseEvent e) { }
public void mouseReleased(MouseEvent e) { }
public BoingPanel()
{
balls = new ArrayList<Ball>();
balls.add(new Ball(100,0)); // adds test ball
balls.get(0).setXVelocity(5);
balls.add(new Ball(100,0));
balls.add(new Ball(400,50));
lines = new ArrayList<Line>();
lines.add(new Line(0, height, width, height));
gameStart();
}
public BoingPanel(int x, int y)
{
width=x;
height=y;
balls = new ArrayList<Ball>();
balls.add(new Ball(100,0)); // adds test ball
balls.get(0).setXVelocity(5);
balls.add(new Ball(100,0));
balls.add(new Ball(400,50));
lines = new ArrayList<Line>();
box = new Container(width, height);
gameStart();
}
@Override
public void mouseDragged(MouseEvent me) {
}
@Override
public void mouseMoved(MouseEvent e) {
}
@Override
public void mouseClicked(MouseEvent e) {
}
@Override
public void mousePressed(MouseEvent e) {
}
@Override
public void mouseReleased(MouseEvent e) {
}
@Override
public void mouseEntered(MouseEvent e) {
}
@Override
public void mouseExited(MouseEvent e) {
}
public void gameStart() {
// Run the game logic in its own thread.
Thread gameThread = new Thread() {
public void run() {
while (true) {
// Execute one time-step for the game
update();
// Refresh the display
repaint();
// Delay and give other thread a chance
try {
Thread.sleep(1000 /updateRate);
} catch (InterruptedException ex) {}
}
}
};
gameThread.start(); // Invoke GaemThread.run()
}
private void update()
{
for(Ball a:balls) //calls balls updated position
{
a.update(box);
}
}
public void paintComponent(Graphics g)
{
box.paint(g);
for(Ball a:balls) //calls balls updated position
{
a.paint(g);
}
for(Line b:lines) //draws lines
{
b.paint(g);
}
}
public void actionPerformed(ActionEvent e)
{
update(); //changes ball position
repaint(); //refreshes image
}
}
是什么导致了这个错误？谢谢！