java - MouseListener 什么都不做

Question

所以我用java写了这段代码。当我按下鼠标按钮时，它应该打印“鼠标点击”，但它什么也没做。

import java.awt.Graphics;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.util.ArrayList;
import java.util.List;

import javax.swing.ImageIcon;
import javax.swing.JPanel;

public class mainPanel extends JPanel implements MouseListener {

    List<Integer> listLoc;
    List<ImageIcon> listImg;

    ImageIcon objPpc;
    ImageIcon ttlSpace;

    public mainPanel(){
        loadImg();
        fillBck(ttlSpace);
        addTtl(objPpc, 1);
        repaint();
    }

    public void fillBck(ImageIcon fillingImg){
        for(int i = 0; i < 16; i++){
            addTtl(fillingImg, i);
        }
    }

    public void loadImg(){
        objPpc = new ImageIcon ("img/obj/ppcBuild1.png");
        ttlSpace = new ImageIcon ("img/ttl/spaceBuild1.png");
        listLoc = new ArrayList<Integer>();
        listImg = new ArrayList<ImageIcon>();
    }

    public void addTtl(ImageIcon addedImg, int addedLoc){

        System.out.println("----- addTtl -----");
        System.out.println(addedImg);
        listImg.add(addedImg);
        System.out.println(addedLoc);
        listLoc.add(addedLoc);
        System.out.println("----- /addTtl -----");
        System.out.println("");
    }

    public void paint (Graphics g){
        super.paint(g);
        for (int i = 0; i < listImg.size(); i ++) {
            g.drawImage((listImg.get(i)).getImage(), (listLoc.get(i) * (this.getWidth() / 16)), 0, (this.getWidth() / 16) , this.getHeight(), null);

        }
    }

    @Override
    public void mouseClicked(MouseEvent e) {
        // TODO Auto-generated method stub
        System.out.println("Mouse Click");
    }

    @Override
    public void mouseEntered(MouseEvent e) {
        // TODO Auto-generated method stub

    }

    @Override
    public void mouseExited(MouseEvent e) {
        // TODO Auto-generated method stub

    }

    @Override
    public void mousePressed(MouseEvent e) {
        // TODO Auto-generated method stub

    }

    @Override
    public void mouseReleased(MouseEvent e) {
        // TODO Auto-generated method stub

    }

}

java 控制台只打印这个，没有错误代码:

----- addTtl -----

img/ttl/spaceBuild1.png
0
----- /addTtl -----

----- addTtl -----
img/ttl/spaceBuild1.png
1
----- /addTtl -----

----- addTtl -----
img/ttl/spaceBuild1.png
2
----- /addTtl -----

----- addTtl -----
img/ttl/spaceBuild1.png
3
----- /addTtl -----

----- addTtl -----
img/ttl/spaceBuild1.png
4
----- /addTtl -----

----- addTtl -----
img/ttl/spaceBuild1.png
5
----- /addTtl -----

----- addTtl -----
img/ttl/spaceBuild1.png
6
----- /addTtl -----

----- addTtl -----
img/ttl/spaceBuild1.png
7
----- /addTtl -----

----- addTtl -----
img/ttl/spaceBuild1.png
8
----- /addTtl -----

----- addTtl -----
img/ttl/spaceBuild1.png
9
----- /addTtl -----

----- addTtl -----
img/ttl/spaceBuild1.png
10
----- /addTtl -----

----- addTtl -----
img/ttl/spaceBuild1.png
11
----- /addTtl -----

----- addTtl -----
img/ttl/spaceBuild1.png
12
----- /addTtl -----

----- addTtl -----
img/ttl/spaceBuild1.png
13
----- /addTtl -----

----- addTtl -----
img/ttl/spaceBuild1.png
14
----- /addTtl -----

----- addTtl -----
img/ttl/spaceBuild1.png
15
----- /addTtl -----

----- addTtl -----
img/obj/ppcBuild1.png
1
----- /addTtl -----

当我按下屏幕上的任何鼠标按钮(甚至滚轮 [MOUSE3])时，它什么都不做。

我该如何解决？

Answer 1

您的代码永远不会向面板添加任何 MouseListener。你应该在某处有这一行:

this.addMouseListener(this);

当您实现 MouseListener 时，这意味着您能够监听鼠标事件。要实际监听鼠标事件，必须将监听器添加(注册)到某个产生鼠标事件的组件。