在JPanel的JLabel顶部将JButton居中

Question

I'm making an odds calculator and I am having some difficulties with the layout. My layout so far is: a JFrame with BorderLayout existing of a top panel with a grid layout positioned north in the JFrame and a center panel positioned in the center of the JFrame. In the center panel I want to draw the player cards and the table plus the cards on the table and a button.

Here's the layout I want to achieve (the cards top panel which is working isn't shown here).

My layout so far:

In this layout 4 cards are shown in the center panel they should be positioned (+1 card extra) in the center of the table (on top of the table). The table is a JLabel added to the center panel, and the cards are buttons. Which layout do I need for the center panel to get the layout I want to achieve? Do I need more panels?

public class OddsCalculator extends JFrame{

JPanel topPanel;
JLabel tablePicture;
JPanel centerPanel;


Card aceClubs;
Card kingClubs;
Card queenClubs;
Card jackClubs;
Card tenClubs;
Card nineClubs;
Card eightClubs;
Card sevenClubs;
Card sixClubs;
Card fiveClubs;
Card fourClubs;
Card threeClubs;
Card twoClubs;

//spades
Card aceSpades;
Card kingSpades;
Card queenSpades;
Card jackSpades;
Card tenSpades;
Card nineSpades;
Card eightSpades;
Card sevenSpades;
Card sixSpades;
Card fiveSpades;
Card fourSpades;
Card threeSpades;
Card twoSpades;

//hearts
Card aceHearts;
Card kingHearts;
Card queenHearts;
Card jackHearts;
Card tenHearts;
Card nineHearts;
Card eightHearts;
Card sevenHearts;
Card sixHearts;
Card fiveHearts;
Card fourHearts;
Card threeHearts;
Card twoHearts;

//diamonds
Card aceDiamonds;
Card kingDiamonds;
Card queenDiamonds;
Card jackDiamonds;
Card tenDiamonds;
Card nineDiamonds;
Card eightDiamonds;
Card sevenDiamonds;
Card sixDiamonds;
Card fiveDiamonds;
Card fourDiamonds;
Card threeDiamonds;
Card twoDiamonds;

Card playerOneCardOne;
Card playerOneCardTwo;
Card playerTwoCardOne;
Card playerTwoCardTwo;
Card playerCardSpotTarget;
Card playerCardSpotSender;

Player player1=new Player();
Player player2=new Player();

Card boardCard1=new Card();
Card boardCard2=new Card();
Card boardCard3=new Card();
Card boardCard4=new Card();

Board board=new Board();



public OddsCalculator(){
    initUI();
}


public void initUI() {
   //cardsPanel=new JPanel(new GridLayout(4,13,0,0));
   setLayout(new BorderLayout());
   topPanel = new JPanel(new GridLayout(4,13,0,0)); 
   centerPanel=new JPanel(); 
   tablePicture = new JLabel(new ImageIcon(this.getClass().getResource(Constants.POKERTABLE_ICON)));

   aceClubs=new Card();
   kingClubs=new Card();
   queenClubs=new Card();
   jackClubs=new Card();
   tenClubs=new Card();
   nineClubs=new Card();
   eightClubs=new Card();
   sevenClubs=new Card();
   sixClubs=new Card();
   fiveClubs=new Card();
   fourClubs=new Card();
   threeClubs=new Card();
   twoClubs=new Card();

   aceSpades=new Card();
   kingSpades=new Card();
   queenSpades=new Card();
   jackSpades=new Card();
   tenSpades=new Card();
   nineSpades=new Card();
   eightSpades=new Card();
   sevenSpades=new Card();
   sixSpades=new Card();
   fiveSpades=new Card();
   fourSpades=new Card();
   threeSpades=new Card();
   twoSpades=new Card();

   aceHearts=new Card();
   kingHearts=new Card();
   queenHearts=new Card();
   jackHearts=new Card();
   tenHearts=new Card();
   nineHearts=new Card();
   eightHearts=new Card();
   sevenHearts=new Card();
   sixHearts=new Card();
   fiveHearts=new Card();
   fourHearts=new Card();
   threeHearts=new Card();
   twoHearts=new Card();

   aceDiamonds=new Card();
   kingDiamonds=new Card();
   queenDiamonds=new Card();
   jackDiamonds=new Card();
   tenDiamonds=new Card();
   nineDiamonds=new Card();
   eightDiamonds=new Card();
   sevenDiamonds=new Card();
   sixDiamonds=new Card();
   fiveDiamonds=new Card();
   fourDiamonds=new Card();
   threeDiamonds=new Card();
   twoDiamonds=new Card();

   playerOneCardOne=new Card();
   playerOneCardTwo=new Card();
   playerTwoCardOne=new Card();
   playerTwoCardTwo=new Card();

   boardCard1=new Card();
   boardCard2=new Card();
   boardCard3=new Card();

   board=new Board();

   //setLayout(new FlowLayout(FlowLayout.LEFT));

   topPanel.setPreferredSize(new Dimension(1200,450));//was 1000/600

   getContentPane().add(topPanel,BorderLayout.NORTH);

   //setSize(1000,1600);
   setDefaultCloseOperation(EXIT_ON_CLOSE);


   aceClubs.suit=Constants.CARD_SUIT_CLUBS;
   aceClubs.kind=Constants.CARD_KIND_ACE;
   aceClubs.iconPath=Constants.ACE_CLUBS_ICON;

   aceClubs.setIcon(new javax.swing.ImageIcon(this.getClass().getResource(aceClubs.iconPath)));
   aceClubs.setBorder(null);
   aceClubs.setContentAreaFilled(false);
   aceClubs.addMouseListener(new java.awt.event.MouseAdapter() {
        public void mouseClicked(java.awt.event.MouseEvent evt) {
            MouseClicked(evt);
        }
    });
   topPanel.add(aceClubs,BorderLayout.PAGE_START);



   getContentPane().add(centerPanel,BorderLayout.CENTER); 

   //BOARD CARD SPOTS
   boardCard1.iconPath=Constants.CARD_BACKSIDE;
   boardCard1.setIcon(new javax.swing.ImageIcon(this.getClass().getResource(boardCard1.iconPath)));
   boardCard1.setBorder(javax.swing.BorderFactory.createLineBorder(new java.awt.Color(0, 0, 0), 5));
   boardCard1.setBorderPainted(false);
   boardCard1.setContentAreaFilled(false);
   boardCard1.addMouseListener(new java.awt.event.MouseAdapter() {
        public void mouseClicked(java.awt.event.MouseEvent evt) {
            PlayerOneMouseClicked(evt);
        }
    });
   boardCard1.boardPosition=1;
   centerPanel.add(boardCard1);

   boardCard2.iconPath=Constants.CARD_BACKSIDE;
   boardCard2.setIcon(new javax.swing.ImageIcon(this.getClass().getResource(boardCard2.iconPath)));
   boardCard2.setBorder(javax.swing.BorderFactory.createLineBorder(new java.awt.Color(0, 0, 0), 5));
   boardCard2.setBorderPainted(false);
   boardCard2.setContentAreaFilled(false);
   boardCard2.addMouseListener(new java.awt.event.MouseAdapter() {
        public void mouseClicked(java.awt.event.MouseEvent evt) {
            PlayerOneMouseClicked(evt);
        }
    });
   //centerPanel.add(boardCard1,SwingConstants.CENTER);
   boardCard2.boardPosition=2;
   centerPanel.add(boardCard2);

   boardCard3.iconPath=Constants.CARD_BACKSIDE;
   boardCard3.setIcon(new javax.swing.ImageIcon(this.getClass().getResource(boardCard3.iconPath)));
   boardCard3.setBorder(javax.swing.BorderFactory.createLineBorder(new java.awt.Color(0, 0, 0), 5));
   boardCard3.setBorderPainted(false);
   boardCard3.setContentAreaFilled(false);
   boardCard3.addMouseListener(new java.awt.event.MouseAdapter() {
        public void mouseClicked(java.awt.event.MouseEvent evt) {
            PlayerOneMouseClicked(evt);
        }
    });
   //centerPanel.add(boardCard1,SwingConstants.CENTER);
   boardCard3.boardPosition=3;
   centerPanel.add(boardCard3);

   boardCard4.iconPath=Constants.CARD_BACKSIDE;
   boardCard4.setIcon(new javax.swing.ImageIcon(this.getClass().getResource(boardCard4.iconPath)));
   boardCard4.setBorder(javax.swing.BorderFactory.createLineBorder(new java.awt.Color(0, 0, 0), 5));
   boardCard4.setBorderPainted(false);
   boardCard4.setContentAreaFilled(false);
   boardCard4.addMouseListener(new java.awt.event.MouseAdapter() {
        public void mouseClicked(java.awt.event.MouseEvent evt) {
            PlayerOneMouseClicked(evt);
        }
    });
   //centerPanel.add(boardCard1,SwingConstants.CENTER);
   boardCard4.boardPosition=4;
   centerPanel.add(boardCard4);

   centerPanel.add(tablePicture); //TABLE





}

 private void MouseClicked(java.awt.event.MouseEvent evt)         
 {                              

     //JButton b=(JButton)evt.getSource();
     playerCardSpotSender=(Card)evt.getSource();
     //System.out.println("Location: "+b.getLocation());
     System.out.println(playerCardSpotSender.suit+" "+playerCardSpotSender.kind);
     //card.setVisible(false);



      if (playerCardSpotTarget != null && playerCardSpotTarget.isBorderPainted()) {
      playerCardSpotSender.setLocation(playerCardSpotTarget.getLocation());
             System.out.println(playerCardSpotTarget.getLocation());
             //add to board flop
             if (playerCardSpotTarget.boardPosition != null &&    playerCardSpotTarget.boardPosition <= Constants.NUMBER_OF_FLOP_CARDS) {


       playerCardSpotSender.setLocation(playerCardSpotSender.getLocation());

        }
     }

}   

private void PlayerOneMouseClicked(java.awt.event.MouseEvent evt){
     //JButton b=(JButton)evt.getSource();
     playerCardSpotTarget=(Card)evt.getSource();

    if(playerCardSpotTarget.isBorderPainted()){
        playerCardSpotTarget.setBorderPainted(false);
    }
    else{
        playerCardSpotTarget.setBorderPainted(true);
    }
}

public static void main(String[] args) {
  OddsCalculator oc=new OddsCalculator();
  oc.setVisible(true);
  oc.pack();

    }
  }

For readability I've only included one card from the top panel in my code snippet.

Card.java

public class Card extends JButton{
  int suit;
  int kind;
  boolean known;
  String iconPath;
  Integer boardPosition;
}

Answer 1

Instead of adding your image as JLabel, look how to render an image as part of the JPanel and then just add your buttons as normal. At the moment the buttons/jlabel are fighting for space.

Googling "Set background image on JPanel" should get you the answer you need, just ignore the results talking about using a JLabel.