Java Swing：僅在縮放JFrame后才會顯示JPanel

Question

我當時正在開發一個迷你二十一點游戲，但我必須進入GUI和Im時遇到一個小問題，我在JFrame中有2個JPanel，一旦運行main方法，只有一個會出現，並且在該區域上會出現一個點我指定了第二個面板的位置。 一旦用鼠標向上或向下或向任何方向縮放JFrame，JPanel就會出現在其正確位置。 我有點糾結於如何解決該問題，因為我嘗試了很多不同的嘗試，但無法解決。 任何幫助是極大的贊賞。 這是代碼：

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import java.awt.BorderLayout;
import java.awt.FlowLayout;
import java.awt.GridBagLayout;
import java.awt.GridBagConstraints;
import java.awt.Color;
import java.awt.GridLayout;
import java.awt.Insets;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener; 

import javax.swing.BorderFactory;
import javax.swing.JFrame ; 
import javax.swing.JButton ;
import javax.swing.JLabel;
import javax.swing.JPanel ;
import javax.swing.JTextArea;
import java.awt.Dimension;
import javax.swing.Box;
import javax.swing.BoxLayout;


public class GUI extends JFrame implements ActionListener {


public GUI(){
    //Constructor for BlackJack 

    ///Frame/////////////////////////////////////////////
    super("BlackJack");  

    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    setBackground(Color.WHITE);
    setLayout(new GridBagLayout());
    setSize(1051,550);
    setResizable(true);
    GridBagConstraints gbc = new GridBagConstraints();
    GridBagConstraints gbc2 = new GridBagConstraints();
    gbc.insets = new Insets(10,10,10,10);
    gbc2.insets= new Insets(10,10,10,10);


    // Creating all the necessary panels.
    JPanel scores = new JPanel(new GridBagLayout());
    JPanel dealer = new JPanel(); 
    JPanel player = new JPanel();
    JPanel bettingArea = new JPanel(new GridBagLayout());
    JPanel messages = new JPanel();  
    messages.setLayout(new BoxLayout(messages,BoxLayout.PAGE_AXIS));



    //Adding the panels to the Frame.

    gbc2.anchor=GridBagConstraints.NORTHEAST;
    add(scores,gbc2);

    gbc2.anchor=GridBagConstraints.LAST_LINE_START;
    add(bettingArea,gbc2);

    gbc2.anchor=GridBagConstraints.LAST_LINE_END;
    add(messages,gbc2);

    // Setting borders for each Panel.
    scores.setBorder(BorderFactory.createLineBorder(Color.DARK_GRAY, 3));
    bettingArea.setBorder(BorderFactory.createLineBorder(Color.DARK_GRAY, 3));
    messages.setBorder(BorderFactory.createLineBorder(Color.BLUE, 3));

    ////////End of Frame/////////////////////////////////////////////////

    //score's Interface //////////////////////////////
    /////////////////////////////////////////////////

    JButton hit = new JButton("Hit");
    JButton check = new JButton("Check");
    JLabel plrScore = new JLabel("Player Score");
    JLabel dlrScore = new JLabel("Dealer Score");

    // Setting Different Border Colors for the Player and Dealer
    plrScore.setBorder(BorderFactory.createLineBorder(Color.BLUE));
    dlrScore.setBorder(BorderFactory.createLineBorder(Color.BLACK));

    // Setting up the GridBagConstraints.
    gbc.gridx=0;
    gbc.gridy=0;
    scores.add(plrScore,gbc);

    gbc.gridx=1;
    gbc.gridy=0;
    scores.add(dlrScore,gbc);

    gbc.gridx=0;
    gbc.gridy=1;
    scores.add(hit,gbc);

    gbc.gridx=1;
    gbc.gridy=1;
    scores.add(check,gbc); 


    //bettingArea's Interface //////////////////////////
    ///////////////////////////////////////////////////
    JButton increaseBet = new JButton("Increase");
    JButton decreaseBet = new JButton("Decrease");
    JTextArea playerBet = new JTextArea("Player Bet");
    JTextArea playerCash = new JTextArea("Player Cash"); 

    // Setting Different Borders for the Objects
    playerBet.setBorder(BorderFactory.createRaisedSoftBevelBorder());
    playerCash.setBorder(BorderFactory.createRaisedSoftBevelBorder());


    // Setting up the GridBagConstraints.
    gbc.gridx=0;
    gbc.gridy=0;
    bettingArea.add(increaseBet,gbc);

    gbc.gridx=1;
    gbc.gridy=0;
    bettingArea.add(playerBet,gbc);

    gbc.gridx=0;
    gbc.gridy=1;
    bettingArea.add(decreaseBet,gbc);

    gbc.gridx=1;
    gbc.gridy=1;
    bettingArea.add(playerCash,gbc);

    ////messages Interface///////////////////// 

    JTextArea msg1 = new JTextArea("Message 1"); 
    JTextArea msg2 = new JTextArea("Message 2"); 
    JTextArea msg3 = new JTextArea("Message 3"); 
    JTextArea msg4 = new JTextArea("Message 4"); 

    messages.add(msg1); 
    messages.add(Box.createRigidArea( new Dimension(0,2)));
    messages.add(msg2);
    messages.add(Box.createRigidArea( new Dimension(0,2)));
    messages.add(msg3);
    messages.add(Box.createRigidArea( new Dimension(0,2)));
    messages.add(msg4);


    //Visibility of Panels & JFrame.
    scores.setVisible(true);
    bettingArea.setVisible(true);
    messages.setVisible(true);
    setVisible(true); 




}





public void actionPerformed(ActionEvent arg0) {
    // TODO Auto-generated method stub

}


// Main Method
public static void main ( String args[]){
    GUI game = new GUI();
}

}

Answer 1

您需要刪除setVisible(true); 從GUI()構造函數。 而是將其放在main()函數和SwingUtilities.invokeLater() ，如下所示：

public static void main ( String args[]){
    SwingUtilities.invokeLater(new Runnable() {
        public void run() {
            new GUI().setVisible(true);
        }
    });
}

Swing GUI更新和渲染任務應在EDT（事件分發線程）中執行。 上面的電話只是為我們做的。