Java 我有一个JApplet，它必须显示3个组件。（2个J板和1个油漆方法）

我有一个任务，其中我必须允许用户使用二次方程绘制图形

我设法画出了图形的框架，现在我正试图显示“控制面板”，供用户输入值

我有4个文件：

• graph.java

• panel.java

• panelB.java

• panelC.java

我的问题是，当我运行代码时，它只显示

panel.java

，即使在它应该显示其他两个面板的容器中也是如此

panel.java 谁能告诉我应该做什么改变来解决这个问题

我对graph.java文件做了一些更改：

import java.awt.BorderLayout;
import java.awt.Container;
import java.awt.Dimension;
import javax.swing.*;

public class GraphApplet extends JApplet{


    public GraphApplet(){
    
    raph p = new Graph();//graph
    
    p.setPreferredSize(new Dimension(760,500));
        conn.add(p,BorderLayout.CENTER);
    }

现在显示的只是图形

关于其他代码，我还对类名做了一些更改：

gnjk；。java

import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.*;
import java.awt.geom.*;
import javax.swing.JPanel;


public class Graph extends JPanel {

public Graph(){
    this.setBackground(Color.yellow);
    }
   
    public void paintComponent(Graphics p) {
    
        super.paintComponent(p);
    
        Graphics2D graph = (Graphics2D)p;
        
        this.setBackground(Color.yellow);//set background color.
        
        int x,y,y1,x1,a,b,p1x,p1y,p2x,p2y;
        
        int xstart = 7;
        int ystart = 1;
        
        int xfinish = 3;

import javax.swing.*;

import java.awt.*;

import javax.swing.JPanel;


public class ControlsA extends JPanel{

public void init (Box g) {
    
    a = Box.createVerticalBox();
    a.add(new JLabel("Please enter the values below:"));
    a.add(new JLabel("h"));
    

}

}

import javax.swing.*;

import java.awt.Component;
import java.awt.Dimension;

public class ControlsB extends JPanel{

public void init (Box b) {

    b = Box.createHorizontalBox();
    b.add(new JLabel("a"));
    JTextField f1 = new JTextField("0.0");
    f1.setMaximumSize(new Dimension(100,30));
    b.add(f1);


}
}

import java.awt.BorderLayout;
import java.awt.Container;

public class GraphApplet extends JApplet{
  public GraphApplet() {
    public void init(){
        SwingUtilities.invokeLater(new Runnable() {
         
         public void run(){
             Container conn = getContentPane();
             conn.setLayout(new BorderLayout());

             Graph z = new Graph();
             conn.add(p,BorderLayout.CENTER);


             fasfae a = new ControlsA(box1);
             conn.add(a,BorderLayout.LINE_START);

            
             adsfawef b = new ControlsB(box2);
             conn.add(b,BorderLayout.PAGE_END);
         }
        });
        }
        }

    
    
    
    /*Container conn = getContentPane();
    conn.setLayout(new BorderLayout());     
    
    Graph p = new Graph();//graph
    
    p.setPreferredSize(new Dimension(460,560));
    conn.add(p,BorderLayout.CENTER);
    
    Box a = new Box(BoxLayout.Y_AXIS);

    a.setPreferredSize(new Dimension(50,50));
    conn.add(a,BorderLayout.EAST);
    
    Box b = new Box(BoxLayout.X_AXIS);
   
    b.setPreferredSize(new Dimension(201,50));
    conn.add(b,BorderLayout.SOUTH);*/
    //this code is commented not to loose it

import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.*;
import java.awt.geom.*;
import javax.swing.JPanel;


class Graph extends JPanel {

public Graph(){
    this.setBackground(Color.yellow);
}
@Override
public Dimension getPreferredSize(){return (new Dimension(460,560)); }

public void paint(Graphics z) {
    
        
    
        Graphics graph = (Graphics2D)z;
        
       
        this.setBackground(Color.yellow).
        
        int x,y,y1,x1,a,b,p1x,p1y,p2x,p2y;
        
        //line co-ordinates
        //the numbers represent the number of boxes on the graph
        int xstart = 7;
        int ystart = 1;
        
        int x = 3;
        int y = 9;
        
        //other variables
        int i = 0;
        int i2 = 0;
        int m = 0;
        int n = 0;
        int m2 = 0;
        int n2 = 0;
        int f2 = 0;
        int g2 = 1;
        
        //ranges
        int f = 5;
        int g = -5;
        
        //change -ve num to +ve
        int g3 = Math.abs(g);
        
        int a1 = g3 + f;
        int b1 = a1;
        
        a = (Height);
        f = (Width);

        }
    }
}

// 6 variables the user has to input

}
@Override
public Dimension getPreferredSize() {return (new Dimension(200,100));}
}

 @Override
 public Dimension getPreferredSize(){return (new Dimension(201,50));}
}

bhfvhn.java

import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.*;
import java.awt.geom.*;
import javax.swing.JPanel;


public class Graph extends JPanel {

public Graph(){
    this.setBackground(Color.yellow);
    }
   
    public void paintComponent(Graphics p) {
    
        super.paintComponent(p);
    
        Graphics2D graph = (Graphics2D)p;
        
        this.setBackground(Color.yellow);//set background color.
        
        int x,y,y1,x1,a,b,p1x,p1y,p2x,p2y;
        
        int xstart = 7;
        int ystart = 1;
        
        int xfinish = 3;

import javax.swing.*;

import java.awt.*;

import javax.swing.JPanel;


public class ControlsA extends JPanel{

public void init (Box g) {
    
    a = Box.createVerticalBox();
    a.add(new JLabel("Please enter the values below:"));
    a.add(new JLabel("h"));
    

}

}

import javax.swing.*;

import java.awt.Component;
import java.awt.Dimension;

public class ControlsB extends JPanel{

public void init (Box b) {

    b = Box.createHorizontalBox();
    b.add(new JLabel("a"));
    JTextField f1 = new JTextField("0.0");
    f1.setMaximumSize(new Dimension(100,30));
    b.add(f1);


}
}

import java.awt.BorderLayout;
import java.awt.Container;

public class GraphApplet extends JApplet{
  public GraphApplet() {
    public void init(){
        SwingUtilities.invokeLater(new Runnable() {
         
         public void run(){
             Container conn = getContentPane();
             conn.setLayout(new BorderLayout());

             Graph z = new Graph();
             conn.add(p,BorderLayout.CENTER);


             fasfae a = new ControlsA(box1);
             conn.add(a,BorderLayout.LINE_START);

            
             adsfawef b = new ControlsB(box2);
             conn.add(b,BorderLayout.PAGE_END);
         }
        });
        }
        }

    
    
    
    /*Container conn = getContentPane();
    conn.setLayout(new BorderLayout());     
    
    Graph p = new Graph();//graph
    
    p.setPreferredSize(new Dimension(460,560));
    conn.add(p,BorderLayout.CENTER);
    
    Box a = new Box(BoxLayout.Y_AXIS);

    a.setPreferredSize(new Dimension(50,50));
    conn.add(a,BorderLayout.EAST);
    
    Box b = new Box(BoxLayout.X_AXIS);
   
    b.setPreferredSize(new Dimension(201,50));
    conn.add(b,BorderLayout.SOUTH);*/
    //this code is commented not to loose it

import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.*;
import java.awt.geom.*;
import javax.swing.JPanel;


class Graph extends JPanel {

public Graph(){
    this.setBackground(Color.yellow);
}
@Override
public Dimension getPreferredSize(){return (new Dimension(460,560)); }

public void paint(Graphics z) {
    
        
    
        Graphics graph = (Graphics2D)z;
        
       
        this.setBackground(Color.yellow).
        
        int x,y,y1,x1,a,b,p1x,p1y,p2x,p2y;
        
        //line co-ordinates
        //the numbers represent the number of boxes on the graph
        int xstart = 7;
        int ystart = 1;
        
        int x = 3;
        int y = 9;
        
        //other variables
        int i = 0;
        int i2 = 0;
        int m = 0;
        int n = 0;
        int m2 = 0;
        int n2 = 0;
        int f2 = 0;
        int g2 = 1;
        
        //ranges
        int f = 5;
        int g = -5;
        
        //change -ve num to +ve
        int g3 = Math.abs(g);
        
        int a1 = g3 + f;
        int b1 = a1;
        
        a = (Height);
        f = (Width);

        }
    }
}

// 6 variables the user has to input

}
@Override
public Dimension getPreferredSize() {return (new Dimension(200,100));}
}

 @Override
 public Dimension getPreferredSize(){return (new Dimension(201,50));}
}

jknmk.java

import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.*;
import java.awt.geom.*;
import javax.swing.JPanel;


public class Graph extends JPanel {

public Graph(){
    this.setBackground(Color.yellow);
    }
   
    public void paintComponent(Graphics p) {
    
        super.paintComponent(p);
    
        Graphics2D graph = (Graphics2D)p;
        
        this.setBackground(Color.yellow);//set background color.
        
        int x,y,y1,x1,a,b,p1x,p1y,p2x,p2y;
        
        int xstart = 7;
        int ystart = 1;
        
        int xfinish = 3;

import javax.swing.*;

import java.awt.*;

import javax.swing.JPanel;


public class ControlsA extends JPanel{

public void init (Box g) {
    
    a = Box.createVerticalBox();
    a.add(new JLabel("Please enter the values below:"));
    a.add(new JLabel("h"));
    

}

}

import javax.swing.*;

import java.awt.Component;
import java.awt.Dimension;

public class ControlsB extends JPanel{

public void init (Box b) {

    b = Box.createHorizontalBox();
    b.add(new JLabel("a"));
    JTextField f1 = new JTextField("0.0");
    f1.setMaximumSize(new Dimension(100,30));
    b.add(f1);


}
}

import java.awt.BorderLayout;
import java.awt.Container;

public class GraphApplet extends JApplet{
  public GraphApplet() {
    public void init(){
        SwingUtilities.invokeLater(new Runnable() {
         
         public void run(){
             Container conn = getContentPane();
             conn.setLayout(new BorderLayout());

             Graph z = new Graph();
             conn.add(p,BorderLayout.CENTER);


             fasfae a = new ControlsA(box1);
             conn.add(a,BorderLayout.LINE_START);

            
             adsfawef b = new ControlsB(box2);
             conn.add(b,BorderLayout.PAGE_END);
         }
        });
        }
        }

    
    
    
    /*Container conn = getContentPane();
    conn.setLayout(new BorderLayout());     
    
    Graph p = new Graph();//graph
    
    p.setPreferredSize(new Dimension(460,560));
    conn.add(p,BorderLayout.CENTER);
    
    Box a = new Box(BoxLayout.Y_AXIS);

    a.setPreferredSize(new Dimension(50,50));
    conn.add(a,BorderLayout.EAST);
    
    Box b = new Box(BoxLayout.X_AXIS);
   
    b.setPreferredSize(new Dimension(201,50));
    conn.add(b,BorderLayout.SOUTH);*/
    //this code is commented not to loose it

import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.*;
import java.awt.geom.*;
import javax.swing.JPanel;


class Graph extends JPanel {

public Graph(){
    this.setBackground(Color.yellow);
}
@Override
public Dimension getPreferredSize(){return (new Dimension(460,560)); }

public void paint(Graphics z) {
    
        
    
        Graphics graph = (Graphics2D)z;
        
       
        this.setBackground(Color.yellow).
        
        int x,y,y1,x1,a,b,p1x,p1y,p2x,p2y;
        
        //line co-ordinates
        //the numbers represent the number of boxes on the graph
        int xstart = 7;
        int ystart = 1;
        
        int x = 3;
        int y = 9;
        
        //other variables
        int i = 0;
        int i2 = 0;
        int m = 0;
        int n = 0;
        int m2 = 0;
        int n2 = 0;
        int f2 = 0;
        int g2 = 1;
        
        //ranges
        int f = 5;
        int g = -5;
        
        //change -ve num to +ve
        int g3 = Math.abs(g);
        
        int a1 = g3 + f;
        int b1 = a1;
        
        a = (Height);
        f = (Width);

        }
    }
}

// 6 variables the user has to input

}
@Override
public Dimension getPreferredSize() {return (new Dimension(200,100));}
}

 @Override
 public Dimension getPreferredSize(){return (new Dimension(201,50));}
}

---

以下是对我的项目的更新：

jkl.java

import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.*;
import java.awt.geom.*;
import javax.swing.JPanel;


public class Graph extends JPanel {

public Graph(){
    this.setBackground(Color.yellow);
    }
   
    public void paintComponent(Graphics p) {
    
        super.paintComponent(p);
    
        Graphics2D graph = (Graphics2D)p;
        
        this.setBackground(Color.yellow);//set background color.
        
        int x,y,y1,x1,a,b,p1x,p1y,p2x,p2y;
        
        int xstart = 7;
        int ystart = 1;
        
        int xfinish = 3;

import javax.swing.*;

import java.awt.*;

import javax.swing.JPanel;


public class ControlsA extends JPanel{

public void init (Box g) {
    
    a = Box.createVerticalBox();
    a.add(new JLabel("Please enter the values below:"));
    a.add(new JLabel("h"));
    

}

}

import javax.swing.*;

import java.awt.Component;
import java.awt.Dimension;

public class ControlsB extends JPanel{

public void init (Box b) {

    b = Box.createHorizontalBox();
    b.add(new JLabel("a"));
    JTextField f1 = new JTextField("0.0");
    f1.setMaximumSize(new Dimension(100,30));
    b.add(f1);


}
}

import java.awt.BorderLayout;
import java.awt.Container;

public class GraphApplet extends JApplet{
  public GraphApplet() {
    public void init(){
        SwingUtilities.invokeLater(new Runnable() {
         
         public void run(){
             Container conn = getContentPane();
             conn.setLayout(new BorderLayout());

             Graph z = new Graph();
             conn.add(p,BorderLayout.CENTER);


             fasfae a = new ControlsA(box1);
             conn.add(a,BorderLayout.LINE_START);

            
             adsfawef b = new ControlsB(box2);
             conn.add(b,BorderLayout.PAGE_END);
         }
        });
        }
        }

    
    
    
    /*Container conn = getContentPane();
    conn.setLayout(new BorderLayout());     
    
    Graph p = new Graph();//graph
    
    p.setPreferredSize(new Dimension(460,560));
    conn.add(p,BorderLayout.CENTER);
    
    Box a = new Box(BoxLayout.Y_AXIS);

    a.setPreferredSize(new Dimension(50,50));
    conn.add(a,BorderLayout.EAST);
    
    Box b = new Box(BoxLayout.X_AXIS);
   
    b.setPreferredSize(new Dimension(201,50));
    conn.add(b,BorderLayout.SOUTH);*/
    //this code is commented not to loose it

import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.*;
import java.awt.geom.*;
import javax.swing.JPanel;


class Graph extends JPanel {

public Graph(){
    this.setBackground(Color.yellow);
}
@Override
public Dimension getPreferredSize(){return (new Dimension(460,560)); }

public void paint(Graphics z) {
    
        
    
        Graphics graph = (Graphics2D)z;
        
       
        this.setBackground(Color.yellow).
        
        int x,y,y1,x1,a,b,p1x,p1y,p2x,p2y;
        
        //line co-ordinates
        //the numbers represent the number of boxes on the graph
        int xstart = 7;
        int ystart = 1;
        
        int x = 3;
        int y = 9;
        
        //other variables
        int i = 0;
        int i2 = 0;
        int m = 0;
        int n = 0;
        int m2 = 0;
        int n2 = 0;
        int f2 = 0;
        int g2 = 1;
        
        //ranges
        int f = 5;
        int g = -5;
        
        //change -ve num to +ve
        int g3 = Math.abs(g);
        
        int a1 = g3 + f;
        int b1 = a1;
        
        a = (Height);
        f = (Width);

        }
    }
}

// 6 variables the user has to input

}
@Override
public Dimension getPreferredSize() {return (new Dimension(200,100));}
}

 @Override
 public Dimension getPreferredSize(){return (new Dimension(201,50));}
}

vtk.java

import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.*;
import java.awt.geom.*;
import javax.swing.JPanel;


public class Graph extends JPanel {

public Graph(){
    this.setBackground(Color.yellow);
    }
   
    public void paintComponent(Graphics p) {
    
        super.paintComponent(p);
    
        Graphics2D graph = (Graphics2D)p;
        
        this.setBackground(Color.yellow);//set background color.
        
        int x,y,y1,x1,a,b,p1x,p1y,p2x,p2y;
        
        int xstart = 7;
        int ystart = 1;
        
        int xfinish = 3;

import javax.swing.*;

import java.awt.*;

import javax.swing.JPanel;


public class ControlsA extends JPanel{

public void init (Box g) {
    
    a = Box.createVerticalBox();
    a.add(new JLabel("Please enter the values below:"));
    a.add(new JLabel("h"));
    

}

}

import javax.swing.*;

import java.awt.Component;
import java.awt.Dimension;

public class ControlsB extends JPanel{

public void init (Box b) {

    b = Box.createHorizontalBox();
    b.add(new JLabel("a"));
    JTextField f1 = new JTextField("0.0");
    f1.setMaximumSize(new Dimension(100,30));
    b.add(f1);


}
}

import java.awt.BorderLayout;
import java.awt.Container;

public class GraphApplet extends JApplet{
  public GraphApplet() {
    public void init(){
        SwingUtilities.invokeLater(new Runnable() {
         
         public void run(){
             Container conn = getContentPane();
             conn.setLayout(new BorderLayout());

             Graph z = new Graph();
             conn.add(p,BorderLayout.CENTER);


             fasfae a = new ControlsA(box1);
             conn.add(a,BorderLayout.LINE_START);

            
             adsfawef b = new ControlsB(box2);
             conn.add(b,BorderLayout.PAGE_END);
         }
        });
        }
        }

    
    
    
    /*Container conn = getContentPane();
    conn.setLayout(new BorderLayout());     
    
    Graph p = new Graph();//graph
    
    p.setPreferredSize(new Dimension(460,560));
    conn.add(p,BorderLayout.CENTER);
    
    Box a = new Box(BoxLayout.Y_AXIS);

    a.setPreferredSize(new Dimension(50,50));
    conn.add(a,BorderLayout.EAST);
    
    Box b = new Box(BoxLayout.X_AXIS);
   
    b.setPreferredSize(new Dimension(201,50));
    conn.add(b,BorderLayout.SOUTH);*/
    //this code is commented not to loose it

import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.*;
import java.awt.geom.*;
import javax.swing.JPanel;


class Graph extends JPanel {

public Graph(){
    this.setBackground(Color.yellow);
}
@Override
public Dimension getPreferredSize(){return (new Dimension(460,560)); }

public void paint(Graphics z) {
    
        
    
        Graphics graph = (Graphics2D)z;
        
       
        this.setBackground(Color.yellow).
        
        int x,y,y1,x1,a,b,p1x,p1y,p2x,p2y;
        
        //line co-ordinates
        //the numbers represent the number of boxes on the graph
        int xstart = 7;
        int ystart = 1;
        
        int x = 3;
        int y = 9;
        
        //other variables
        int i = 0;
        int i2 = 0;
        int m = 0;
        int n = 0;
        int m2 = 0;
        int n2 = 0;
        int f2 = 0;
        int g2 = 1;
        
        //ranges
        int f = 5;
        int g = -5;
        
        //change -ve num to +ve
        int g3 = Math.abs(g);
        
        int a1 = g3 + f;
        int b1 = a1;
        
        a = (Height);
        f = (Width);

        }
    }
}

// 6 variables the user has to input

}
@Override
public Dimension getPreferredSize() {return (new Dimension(200,100));}
}

 @Override
 public Dimension getPreferredSize(){return (new Dimension(201,50));}
}

nllkl.java

import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.*;
import java.awt.geom.*;
import javax.swing.JPanel;


public class Graph extends JPanel {

public Graph(){
    this.setBackground(Color.yellow);
    }
   
    public void paintComponent(Graphics p) {
    
        super.paintComponent(p);
    
        Graphics2D graph = (Graphics2D)p;
        
        this.setBackground(Color.yellow);//set background color.
        
        int x,y,y1,x1,a,b,p1x,p1y,p2x,p2y;
        
        int xstart = 7;
        int ystart = 1;
        
        int xfinish = 3;

import javax.swing.*;

import java.awt.*;

import javax.swing.JPanel;


public class ControlsA extends JPanel{

public void init (Box g) {
    
    a = Box.createVerticalBox();
    a.add(new JLabel("Please enter the values below:"));
    a.add(new JLabel("h"));
    

}

}

import javax.swing.*;

import java.awt.Component;
import java.awt.Dimension;

public class ControlsB extends JPanel{

public void init (Box b) {

    b = Box.createHorizontalBox();
    b.add(new JLabel("a"));
    JTextField f1 = new JTextField("0.0");
    f1.setMaximumSize(new Dimension(100,30));
    b.add(f1);


}
}

import java.awt.BorderLayout;
import java.awt.Container;

public class GraphApplet extends JApplet{
  public GraphApplet() {
    public void init(){
        SwingUtilities.invokeLater(new Runnable() {
         
         public void run(){
             Container conn = getContentPane();
             conn.setLayout(new BorderLayout());

             Graph z = new Graph();
             conn.add(p,BorderLayout.CENTER);


             fasfae a = new ControlsA(box1);
             conn.add(a,BorderLayout.LINE_START);

            
             adsfawef b = new ControlsB(box2);
             conn.add(b,BorderLayout.PAGE_END);
         }
        });
        }
        }

    
    
    
    /*Container conn = getContentPane();
    conn.setLayout(new BorderLayout());     
    
    Graph p = new Graph();//graph
    
    p.setPreferredSize(new Dimension(460,560));
    conn.add(p,BorderLayout.CENTER);
    
    Box a = new Box(BoxLayout.Y_AXIS);

    a.setPreferredSize(new Dimension(50,50));
    conn.add(a,BorderLayout.EAST);
    
    Box b = new Box(BoxLayout.X_AXIS);
   
    b.setPreferredSize(new Dimension(201,50));
    conn.add(b,BorderLayout.SOUTH);*/
    //this code is commented not to loose it

import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.*;
import java.awt.geom.*;
import javax.swing.JPanel;


class Graph extends JPanel {

public Graph(){
    this.setBackground(Color.yellow);
}
@Override
public Dimension getPreferredSize(){return (new Dimension(460,560)); }

public void paint(Graphics z) {
    
        
    
        Graphics graph = (Graphics2D)z;
        
       
        this.setBackground(Color.yellow).
        
        int x,y,y1,x1,a,b,p1x,p1y,p2x,p2y;
        
        //line co-ordinates
        //the numbers represent the number of boxes on the graph
        int xstart = 7;
        int ystart = 1;
        
        int x = 3;
        int y = 9;
        
        //other variables
        int i = 0;
        int i2 = 0;
        int m = 0;
        int n = 0;
        int m2 = 0;
        int n2 = 0;
        int f2 = 0;
        int g2 = 1;
        
        //ranges
        int f = 5;
        int g = -5;
        
        //change -ve num to +ve
        int g3 = Math.abs(g);
        
        int a1 = g3 + f;
        int b1 = a1;
        
        a = (Height);
        f = (Width);

        }
    }
}

// 6 variables the user has to input

}
@Override
public Dimension getPreferredSize() {return (new Dimension(200,100));}
}

 @Override
 public Dimension getPreferredSize(){return (new Dimension(201,50));}
}

---

仍然没有改善。我无法理解发生了什么。

该代码中的主要问题是：

小程序正在添加3个

面板

实例，而不是

面板

、

面板B

和

面板C

各一个实例

无论是

panelB

还是

panelC

都不会将

框添加到面板中，因此它不会出现

您在代码中指出，

面板B

应该垂直对齐，这意味着它更适合

边界布局的
行开始（
西
），而不是
北

public void paint（Graphics p）{..

对于

panel

是错误的。因为

panel

是Swing

JPanel

它应该是

public void paintComponent（Graphics p）{..

一旦这些事情得到处理，它可能就是这样出现的

其他问题

• 需要扩展类的唯一代码是小程序本身和

  面板

  。事实上，甚至

  面板

  也可以更改为在

  JLabel

  中显示

  缓冲区图像

  （图形）

• panelB

  和

  panelC

  是完全冗余的，只需将一个

  框直接添加到所需父组件的布局区域即可

• 命名法是错误的。
• Java类名应该是

  EachWordUpperCase

• 使用有意义的类名-小程序可能是

  GraphApplet

  ，图形区域

  Graph

  ，…我不确定最后两个面板的名称，因为它们带有相同的组件。如果只有一个，我可以将其称为

  控件

  ，作为一个类（这太过分了），或

  控件

  ，如果它是普通

  JPanel

  或

  框

  的实例
• 在这种情况下，不建议调用设置最大或首选大小。唯一可以对其进行设置的情况是图形本身的首选大小，但由于它出现在小程序的

  中心

  ，因此大小将由HTML中指定的小程序宽度/高度减去其他组件的自然大小来建议ents（中心

  组件将获得“剩余空间”）

更新 …如何更改小程序中的代码，以便小程序在每个面板（？）中添加一个

更改：

panel a = new panel();//vertical

至：

panelB a = new panelB(new Box(BoxLayout.Y_AXIS));//vertical

是最简单的方法。请注意，如果您决定直接添加

框

，它会发生变化

Box a = new Box(BoxLayout.Y_AXIS);//vertical

---

请现在尝试运行此代码，告诉我这是否更接近您想要的？如果是，请让我知道，以便我可以删除我的答案。请注意我所做的更改：

• 在您的

  PanelC

  类中，这里不使用

  init（）

  方法，而是使用 制造了一个构造器
• 在Graph类中，setPreferredSizes（…） 调用，而是为每个调用重写了

  getPreferredSize（）

  类扩展

  JPanel

  。为此，请访问每个类面板、面板B和 小组C
• 最后，我更改了提供给

  JPanel

  的维度值， 那就是转到

  左侧/LINE\u START

  侧，转到可以 被看见
• 最好的改变是使用EDT事件调度线程，看起来像你 真的不知道

---

import java.awt.*；
导入java.awt.geom.*；
导入javax.swing.*；
公共类图扩展JApplet{
公共void init（）{
SwingUtilities.invokeLater（新的Runnable（）
{
公开募捐
{
容器conn=getContentPane（）；
conn.setLayout（新的BorderLayout（））；
Panel p=new Panel（）；//图形
连接添加（p，边界布局中心）；
框1=新框（框布局Y_轴）；
PanelB a=新PanelB（框1）；//垂直
连接添加（a，边界布局。线_起点）；
Box-box2=新框（BoxLayout.X_轴）；
PanelC b=新的PanelC（框2）；//水平
连接添加（b，边界布局，第_页结束）；
}
});
}
}
类面板扩展了JPanel{
公共事务委员会（）{
这个.背景（颜色.黄色）；
}
@凌驾
公共维度getPreferredSize（）
{   
返回（新维度（460560））；
}
公共组件（图形p）{
超级组分（p）；
Graphics2D图形=（Graphics2D）p；
维度appletSize=this.getSize（）；
int appletHeight=（int）（appletSize.height）；
int appletWidth=appletSize.width；
this.setBackground（Color.yellow）；//设置背景色。
int x，y，y1，x1，a，b，p1x，p1y，p2x，p2y；