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不知道为什么我的组件在窗体不显示
import javax.swing.JFrame;
import javax.swing.JLabel;
import java.io.File;
import java.awt.image.BufferedImage;
import java.io.IOException;
import javax.imageio.ImageIO;
import java.awt.Graphics;
import java.awt.Font;
import java.awt.Color;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import javax.swing.JOptionPane;
import java.awt.Container;

  public class Fivechess extends JFrame implements MouseListener{
   JLabel l1;
   JLabel l2;
   JLabel l3;
   JLabel l4;
  // Container cp;
BufferedImage image=null;
int x=0;
int y=0;
int allChess[][]=new int[19][19];
boolean isBlack=true;
boolean isWin=true;
boolean canPlay=true;
String message="黑方先行";
public Fivechess(){
this.setTitle("五子棋");
this.setSize(500,600);
this.setLocation(200,200);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

this.addMouseListener(this);
try{
      this.image=ImageIO.read(new File("E:/src/五子棋/mini.jpg"));

      }
      catch(IOException e){
       e.printStackTrace();
      }
l1=new JLabel("游戏开始");
this.getContentPane().add(l1);
l1.setBounds(410,85,30,40);
l2=new JLabel("游戏设置");
l2.setBounds(410,115,30,40);
this.getContentPane().add(l2);
l3=new JLabel("退出");
l3.setBounds(410,145,30,40);
this.getContentPane().add(l3);
l4=new JLabel("关于");
l4.setBounds(410,175,30,40);
this.getContentPane().add(l4);
this.setVisible(true);
}
我是初学者 --------------------编程问答-------------------- 你的组件就没容器装。 --------------------编程问答-------------------- 我还是不太懂  我又改了一下
public class Fivechess extends JFrame implements MouseListener{
   JButton l1;
    JButton l2;
   JButton l3;
    JButton l4;
// Container cp;
BufferedImage image=null;
int x=0;
int y=0;
int allChess[][]=new int[19][19];
boolean isBlack=true;
boolean isWin=true;
boolean canPlay=true;
String message="黑方先行";
public Fivechess(){
// p1=new JPanel();
//     cp=getContentPane();
this.setTitle("五子棋");
this.setSize(500,600);
this.setLocation(200,200);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

this.addMouseListener(this);
try{
      this.image=ImageIO.read(new File("E:/src/五子棋/mini.jpg"));

      }
      catch(IOException e){
       e.printStackTrace();
      }
//       p1.setLayout(new BorderLayout());
l1=new JButton("游戏开始");
this.add(l1);
l1.setBounds(410,50,80,90);
this.add(p1);
l2=new JButton("游戏设置");
l2.setBounds(410,130,80,90);
this.add(l2);
l3=new JButton("退出");
l3.setBounds(410,210,80,90);
this.add(l3);
l4=new JButton("关于");
l4.setBounds(410,290,80,90);
this.add(l4);

this.setVisible(true);
}
JFrame是一个容器吧，用this加在frame上，可是我的setbounds好像不起作用

补充：Java ,  Java相关