当某个事件发生时，我希望图像改变但不会发生。
这是代码：
game.add(bbol);
if (flashed == 1) {
bbol.setIcon(bboH);
} else {
}
我是否需要刷新game面板？
修改
import java.awt.Color;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.util.ArrayList;
import java.util.Random;
import javax.swing.BorderFactory;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.Timer;
import javax.swing.border.Border;
public class BeeBee extends JFrame implements ActionListener, MouseListener {
private static final long serialVersionUID = 1L;
private JFrame frame = new JFrame("BB8 Says");
private JPanel game;
private JPanel menu;
ImageIcon bbegif = new ImageIcon("tumblr_o0c57n9gfv1tha1vgo1_r3_250.gif");
public static final int WIDTH = 800, HEIGHT = 800;
public int flashed = 0, glowTime, dark, ticks, indexPattern;
public boolean creatingPattern = true;
public ArrayList<Integer> pattern;
public Random random;
private boolean gameOver;
public int counter;
public int temp;
public int score;
//these are the images, replace them if you like
public ImageIcon bbb = new ImageIcon("bbb.gif");
public JLabel bbbl = new JLabel(bbb);
public ImageIcon bbbH = new ImageIcon("bbbH.gif");
public ImageIcon bbg = new ImageIcon("bbg.gif");
public JLabel bbgl = new JLabel(bbg);
public ImageIcon bbgH = new ImageIcon("bbgH.gif");
public ImageIcon bbgr = new ImageIcon("bbgr.gif");
public JLabel bbgrl = new JLabel(bbgr);
public ImageIcon bbgrH = new ImageIcon("bbgrH.gif");
public ImageIcon bbo = new ImageIcon("bbor.gif");
public JLabel bbol = new JLabel(bbo);
public ImageIcon bboH = new ImageIcon("bborH.gif");
public ImageIcon unhap = new ImageIcon("unhap.gif");
public JLabel unhapl = new JLabel(unhap);
//these are the images, replace them if you like
public BeeBee()
{
mainmenu();
}
public void start()
{
random = new Random();
pattern = new ArrayList<Integer>();
indexPattern = 0;
dark = 2;
flashed = 0;
ticks = 0;
}
public void actionPerformed(ActionEvent e)
{
ticks++;
if (ticks % 20 == 0)
{
flashed = 0;
if (dark >= 0)
{
dark--;
}}
if (creatingPattern)
{
if (dark <= 0)
{
if (indexPattern >= pattern.size())
{
flashed = random.nextInt(40) % 4 + 1;
pattern.add(flashed);
indexPattern = 0;
creatingPattern = false;
}
else
{
flashed = pattern.get(indexPattern);
indexPattern++;
}
dark = 2;
}}
else if (indexPattern == pattern.size())
{
creatingPattern = true;
indexPattern = 0;
dark = 2;
}}
public void mainmenu()
{
Timer timer = new Timer(20, this);
start();
timer.start();
frame.setSize(WIDTH +7, HEIGHT +30);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setResizable(false);
menu = new JPanel();
game = new JPanel();
menu.setBackground(Color.yellow);
game.setBackground(Color.yellow);
JButton button = new JButton("Start");
button.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
frame.setContentPane(game);
frame.invalidate();
frame.validate();
};
});
menu.add(button);
gamme();
frame.add(menu);
frame.setVisible(true);
}
public void gamme()
{
Border border = BorderFactory.createLineBorder(Color.black, 5);
bbol.setBorder(border);
bbgl.setBorder(border);
bbgrl.setBorder(border);
bbbl.setBorder(border);
game.setLayout(new GridLayout(2,2));
game.add(bbol);
game.add(bbgl);
game.add(bbgrl);
game.add(bbbl);
}
public static void main(String[]args)
{
new BeeBee();
}
@Override
public void mousePressed(MouseEvent e)
{
int x = e.getX(), y = e.getY();
if (!creatingPattern && !gameOver)
{
if (x>0 && x<WIDTH/2 && y>0 && y<HEIGHT/2)
{
flashed = 1;
ticks = 1;
bbol.setIcon(bboH);
}
else if (x>WIDTH/2 && x<WIDTH && y>0 && y<HEIGHT/2)
{
flashed = 2;
ticks = 1;
bbgl.setIcon(bbgH);
}
else if (x>0 && x<WIDTH/2 && y>HEIGHT/2 && y<HEIGHT)
{
flashed = 3;
ticks = 1;
bbgrl.setIcon(bbgrH);
}
else if (x>WIDTH/2 && x<WIDTH && y>HEIGHT/2 && y<HEIGHT)
{
flashed = 4;
ticks = 1;
bbbl.setIcon(bbbH);
}
if (flashed != 0)
{
if (pattern.get(indexPattern)==flashed)
{
indexPattern++;
}
else
{
gameOver = true;
}
}
else
{
start();
gameOver = true;
}}
else if (gameOver)
{
start();
gameOver = false;
}
if (flashed == 1) {
bbol.setIcon(bboH);
} else
{
bbol.setIcon(bbo);
}
if (flashed == 2) {
bbgl.setIcon(bbgH);
} else
{
bbgl.setIcon(bbg);
}
if (flashed == 3) {
bbgrl.setIcon(bbgrH);
} else
{
bbgrl.setIcon(bbgr);
}
if (flashed == 4) {
bbbl.setIcon(bbbH);
} else
{
bbbl.setIcon(bbb);
}
game.repaint();
}
@Override
public void mouseClicked(MouseEvent e)
{}
@Override
public void mouseEntered(MouseEvent e)
{}
@Override
public void mouseExited(MouseEvent e)
{}
@Override
public void mouseReleased(MouseEvent e)
{}
}
答案 0 :(得分：3)
setIcon(...)应足以更改JLabel中的图像。我怀疑你是如何添加JLabel的。如果您在程序运行期间添加组件，则必须在容器上调用revalidate()和repaint()，即接受新JLabel的JPanel。通常最好在程序启动时添加JLabel，而不必担心这些问题。甲
此外，什么事件会触发此更改？您的问题和代码不足以让我们确定。我脑海中的某些事情令我担心你还没有编写事件监听器，因为我们没有看到上面的任何代码表明上面的代码存在于监听器中。请澄清。
如果仍然卡住，请创建并发布有效的minimal example program。
你还没有发布有效的mcve，所以我们仍然需要猜测（请阅读链接），
但是在您的MouseListener中，您正在更改闪烁字段的状态，但您没有调用任何会更改图像的代码。我怀疑您发布的关键代码：
if (flashed == 1)
{
bbol.setIcon(bboH);
} else {
}
出现在GUI创建代码中。如果是这样，则只调用一次，并且仅使用闪烁的原始值。如果您更改闪烁字段的值，则不会神奇地重新调用此代码，而是您必须自己调用。换句话说，此代码应该在MouseListener中。
同样，如果您需要更多帮助，请发布此处发布的有效mcve代码作为代码格式的文本，我们可以实际编译并运行。
此外，如果你想要一个闪烁的图标，那么你将需要创建并使用一个Swing Timer，一个每隔xxx毫秒交换图标的Swing Timer。
例如：
import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.event.*;
import java.awt.image.BufferedImage;
import javax.swing.*;
@SuppressWarnings("serial")
public class BlinkingIcon extends JPanel {
private static final int IMG_WIDTH = 200;
private static final int GAP = 8;
private static final int TIMER_DELAY = 100;
// index into icons array
private int iconIndex = 0;
// array of image icons
private Icon[] icons = new Icon[2];
// JLabel that displays the icons
private JLabel mainLabel = new JLabel();
// Swing Timer that when started swaps the icons
private Timer flashingTimer = new Timer(TIMER_DELAY, new TimerListener());
public BlinkingIcon() {
// fill icons array with icons
icons[0] = createIcon(Color.WHITE);
icons[1] = createIcon(Color.RED);
// add the first icon to the JLabel
mainLabel.setIcon(icons[iconIndex]);
// add the JLabel to the main JPanel, the GUI
add(mainLabel);
// add a MouseListener to the JLabel
// one that turns the flashing timer on and off
mainLabel.addMouseListener(new MouseAdapter() {
@Override
public void mousePressed(MouseEvent e) {
if (flashingTimer.isRunning()) {
flashingTimer.stop();
} else {
flashingTimer.start();
}
}
});
}
// for this example, I will create a simple icon that's little more than
// a color circle, but any icons would work
private Icon createIcon(Color white) {
BufferedImage img = new BufferedImage(IMG_WIDTH, IMG_WIDTH, BufferedImage.TYPE_INT_ARGB);
Graphics2D g2 = img.createGraphics();
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g2.setColor(white);
g2.fillOval(GAP, GAP, IMG_WIDTH - 2 * GAP, IMG_WIDTH - 2 * GAP);
g2.setStroke(new BasicStroke((float) GAP));
g2.setColor(Color.BLACK);
g2.drawOval(GAP, GAP, IMG_WIDTH - 2 * GAP, IMG_WIDTH - 2 * GAP);
g2.dispose();
Icon icon = new ImageIcon(img);
return icon;
}
// ActionListener for our flashingTimer
private class TimerListener implements ActionListener {
@Override
public void actionPerformed(ActionEvent e) {
// add one to the iconIndex, the index to the icons array
iconIndex++;
iconIndex %= icons.length; // set to 0 if it reaches length of array
mainLabel.setIcon(icons[iconIndex]); // swap the icon!
}
}
private static void createAndShowGui() {
BlinkingIcon mainPanel = new BlinkingIcon();
JFrame frame = new JFrame("Blinking Icon");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
关于您发布的代码，您有MouseListener代码但是将其添加到没有组件，并且只有将它们附加到某些内容时才能使用侦听器，例如
game.addMouseListener(this);