Java JFrame背景颜色不起作用
我试过用：
frame1.getContentPane().setBackground(Color.yellow); 但它没有用。 谁能帮我？
import java.awt.*; import java.awt.Color; public class PlayGame { public static void main(String[] args) { GameFrame frame1 = new GameFrame(); frame1.getContentPane().setBackground(Color.yellow); // Set Icon Image icon = Toolkit.getDefaultToolkit().getImage("image/poker_icon.gif"); frame1.setIconImage(icon); frame1.setVisible(true); frame1.setSize(600, 700); frame1.setTitle("Card Game"); // Set to exit on close frame1.setDefaultCloseOperation(GameFrame.EXIT_ON_CLOSE); } }
GameFrame
import javax.swing.*; import java.awt.*; import java.awt.event.*; public class GameFrame extends JFrame implements ActionListener { private JPanel topPnl, btmPnl, pcPnl, mainPnl; private JPanel titlePnl, playerPnl, computerPnl; private JLabel titleLbl, playerLbl, computerLbl; private JLabel testTextBox1, testTextBox2; private ImageIcon playerIcon, computerIcon; // private JPanel pickCardPnl, pickCardTitlePnl, cardPnl, resultPnl, optionPnl; private JLabel pickCardTitleLbl; private JLabel card1Lbl, card2Lbl, card3Lbl, card4Lbl, card5Lbl; private JLabel resultLbl; private JButton restartBtn, showCardBtn, exitBtn; private JButton card1Btn, card2Btn, card3Btn, card4Btn, card5Btn; private ImageIcon card1Pic, card2Pic, card3Pic, card4Pic, card5Pic; private JButton playerBtn, computerBtn; private ImageIcon playerPic; private String[] card = new String[53]; private String name; // ArrayInt al; public GameFrame() { // a1 = new Array(); //a1.generateRandom(); setCard(); setName(); // Top Panel ///////////////////////////////////// mainPnl = new JPanel(new BorderLayout()); topPnl = new JPanel(new BorderLayout(50, 0)); titlePnl = new JPanel(); pcPnl = new JPanel(new GridLayout(1, 2, 10, 10)); playerPnl = new JPanel(new BorderLayout(10, 10)); computerPnl = new JPanel(new BorderLayout(10, 10)); // Title Panel titleLbl = new JLabel("Card Game"); titlePnl.add(titleLbl); // Player Panel playerIcon = new ImageIcon("image/player.png"); playerLbl = new JLabel(name, playerIcon, JLabel.CENTER); playerPnl.add(playerLbl, BorderLayout.NORTH); playerPic = new ImageIcon("image/unknwon.png"); playerBtn = new JButton(playerPic); playerPnl.add(playerBtn, BorderLayout.CENTER); playerBtn.setContentAreaFilled(false); playerBtn.setBorder(BorderFactory.createEmptyBorder()); // Computer Panel computerIcon = new ImageIcon("image/computer.png"); computerLbl = new JLabel("Computer:", computerIcon, JLabel.CENTER); computerPnl.add(computerLbl, BorderLayout.NORTH); playerPic = new ImageIcon("image/back.png"); computerBtn = new JButton(playerPic); computerPnl.add(computerBtn, BorderLayout.CENTER); computerBtn.setContentAreaFilled(false); computerBtn.setBorder(BorderFactory.createEmptyBorder()); pcPnl.add(playerPnl); pcPnl.add(computerPnl); // Add panel into Top Panel topPnl.add(titlePnl, BorderLayout.NORTH); topPnl.add(pcPnl, BorderLayout.CENTER); // Bottom Panel ///////////////////////////////////// btmPnl = new JPanel(new BorderLayout()); pickCardPnl = new JPanel(new BorderLayout()); pickCardTitlePnl = new JPanel(); cardPnl = new JPanel(new GridLayout(1, 5, 5, 5)); resultPnl = new JPanel(); optionPnl = new JPanel(new GridLayout(1, 3, 5, 5)); // Pick Card Panel pickCardTitleLbl = new JLabel("Pick Your Card:"); pickCardPnl.add(pickCardTitleLbl, BorderLayout.NORTH); card1Pic = new ImageIcon(card[1]); card1Btn = new JButton(card1Pic); cardPnl.add(card1Btn); card1Btn.addActionListener(this); card2Pic = new ImageIcon(card[2]); card2Btn = new JButton(card2Pic); cardPnl.add(card2Btn); card2Btn.addActionListener(this); card3Pic = new ImageIcon(card[3]); card3Btn = new JButton(card3Pic); cardPnl.add(card3Btn); card3Btn.addActionListener(this); card4Pic = new ImageIcon(card[4]); card4Btn = new JButton(card4Pic); cardPnl.add(card4Btn); card4Btn.addActionListener(this); card5Pic = new ImageIcon(card[5]); card5Btn = new JButton(card5Pic); cardPnl.add(card5Btn); card5Btn.addActionListener(this); // new ImageIcon(a1.getRandomNumber); pickCardPnl.add(cardPnl, BorderLayout.CENTER); card1Btn.setContentAreaFilled(false); card1Btn.setBorder(BorderFactory.createEmptyBorder()); card2Btn.setContentAreaFilled(false); card2Btn.setBorder(BorderFactory.createEmptyBorder()); card3Btn.setContentAreaFilled(false); card3Btn.setBorder(BorderFactory.createEmptyBorder()); card4Btn.setContentAreaFilled(false); card4Btn.setBorder(BorderFactory.createEmptyBorder()); card5Btn.setContentAreaFilled(false); card5Btn.setBorder(BorderFactory.createEmptyBorder()); // Result Panel setCard(); resultLbl = new JLabel("adasdadadasdasdasdasd"); resultPnl.add(resultLbl); // Option Panel restartBtn = new JButton("Restart"); optionPnl.add(restartBtn); restartBtn.addActionListener(this); showCardBtn = new JButton("Show Cards"); optionPnl.add(showCardBtn); showCardBtn.addActionListener(this); exitBtn = new JButton("Exit"); optionPnl.add(exitBtn); exitBtn.addActionListener(this); // Add panel into Bottom Panel btmPnl.add(pickCardPnl, BorderLayout.NORTH); btmPnl.add(resultPnl, BorderLayout.CENTER); btmPnl.add(optionPnl, BorderLayout.SOUTH); // mainPnl.add(topPnl, BorderLayout.NORTH); // add(midPNL, BorderLayout.CENTER); mainPnl.add(btmPnl, BorderLayout.CENTER); add(mainPnl); // Menu bar JMenuBar menuBar = new JMenuBar(); JMenu menu = new JMenu("Game"); menuBar.add(menu); JMenuItem item3 = new JMenuItem("Change Name"); item3.addActionListener(this); menu.add(item3); JMenuItem item = new JMenuItem("Change Card Deck"); item.addActionListener(this); menu.add(item); JMenu subMenu = new JMenu("Change BackGround"); subMenu.addActionListener(this); menu.add(subMenu); JMenuItem subItem = new JMenuItem("Blue"); subItem.addActionListener(this); subMenu.add(subItem); JMenuItem subItem2 = new JMenuItem("Green"); subItem2.addActionListener(this); subMenu.add(subItem2); // menu.addSeparator(); // JMenuItem item4 = new JMenuItem("Quit"); item4.addActionListener(this); menu.add(item4); setJMenuBar(menuBar); } //End of GameFrame public void setCard() { GenRandom g1 = new GenRandom(); g1.GenRandomCard(); int[] allCard = new int[11]; allCard = g1.getAllCard(); for (int i = 1; i <= 10; i++) { card[i] = "image/card/" + allCard[i] + ".png"; } } public void setName() { // name = JOptionPane.showInputDialog(null, "Please Enter Your Name", "Welcome", JOptionPane.QUESTION_MESSAGE) + ":"; } public void actionPerformed(ActionEvent e) { if (e.getSource() == card1Btn) { playerBtn.setIcon(card1Pic); card1Btn.setEnabled(false); } if (e.getSource() == card2Btn) { playerBtn.setIcon(card2Pic); card2Btn.setEnabled(false); } if (e.getSource() == card3Btn) { playerBtn.setIcon(card3Pic); card3Btn.setEnabled(false); } if (e.getSource() == card4Btn) { playerBtn.setIcon(card4Pic); card4Btn.setEnabled(false); } if (e.getSource() == card5Btn) { playerBtn.setIcon(card5Pic); card5Btn.setEnabled(false); } if (e.getSource() == restartBtn) { new AePlayWave("sound/jet.wav").start(); JOptionPane.showMessageDialog(null, "Restart Button "); } if (e.getSource() == exitBtn) { /* long start = System.currentTimeMillis(); long end = start + 4 * 1000; // 60 seconds * 1000 ms/sec while (System.currentTimeMillis() < end) { // run new AePlayWave("sound/jet.wav").start(); }*/ System.exit(0); } } }
既然你没有发布SSCCE ，我会为你做的。 这显示了如何更改JFrame的背景颜色。 从这开始，您可以开始向JFrame添加组件并查看出错的地方，而不是让我们查看几百行代码。
import javax.swing.JFrame; import java.awt.Color; import java.awt.EventQueue; public class ColoredFrame { public static void main( String[] args ) { EventQueue.invokeLater( new Runnable() { @Override public void run() { JFrame frame = new JFrame( "TestFrame" ); frame.getContentPane().setBackground( Color.PINK ); //frame contains nothing, so set size frame.setSize( 200, 200 ); frame.setVisible( true ); frame.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE ); } } ); } }
您应该为JPanel提供背景颜色，然后在JFrame中使用此JPanel，而不是直接向您的JFrame提供背景。
只需把你的setVisible(true); 在构造函数的末尾。
此外，您已在JFrame上添加了mainPnl ，因此更改JFrame的颜色将毫无用处，
所以不要写作
add(mainPnl);
在你的GameFrame类中，你最好使用
setContentPane(mainPnl);
for frame1.getContentPane().setBackground(Color.YELLOW); 上class。
希望这可能有所帮助
问候
我知道这是一个非常古老的问题，但对于寻找正确答案的其他人来说，这也可以写成如下：
frame1.getContentPane().setBackground(new Color (255,255,102)); //or whatever color you want in the RGB range