图像在鼠标框架中没有新鲜点击在Java中

第一次在三个不同arrays的Jframe上显示三个随机图像。 甚至触发了MouseClicked方法，但帧中没有刷新图像。 我想每次点击Frame时刷新三个随机图像。 请帮忙

import java.awt.*; import java.awt.event.MouseAdapter; import java.awt.event.MouseEvent; import java.awt.event.MouseListener; import java.util.Random; import javax.swing.*; public class Cards extends JFrame implements MouseListener { public static void main(String[] args) { JFrame frame = new Cards(); frame.setTitle("Cards"); frame.setSize(500, 500); frame.setLocationRelativeTo(null); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.setVisible(true); new Cards(); } public Cards() { this.getContentPane().addMouseListener(this); cards1(); cards2(); cards3(); } public void cards1() { ImageIcon[] images = new ImageIcon[10]; for (int i = 1; i < images.length; i++) { images[i] = new ImageIcon("Drawables//Images//" + i + ".png"); } int[] threeRandoms = new int[1]; Random ran = new Random(); for (int i = 0; i < threeRandoms.length; i++) { threeRandoms[i] = ran.nextInt(10); } setLayout(new GridLayout(1, 4, 5, 5)); add(new JLabel(images[threeRandoms[0]])); } public void cards2() { ImageIcon[] images = new ImageIcon[10]; for (int i = 1; i < images.length; i++) { images[i] = new ImageIcon("Drawables//Images1//" + i + ".png"); } int[] threeRandoms = new int[1]; Random ran = new Random(); for (int i = 0; i < threeRandoms.length; i++) { threeRandoms[i] = ran.nextInt(10); } setLayout(new GridLayout(1, 4, 5, 5)); add(new JLabel(images[threeRandoms[0]])); } public void cards3() { // this.getContentPane().addMouseListener(this); ImageIcon[] images = new ImageIcon[10]; for (int i = 1; i < images.length; i++) { images[i] = new ImageIcon("Drawables//Images2//" + i + ".png"); } int[] threeRandoms = new int[1]; Random ran = new Random(); for (int i = 0; i < threeRandoms.length; i++) { threeRandoms[i] = ran.nextInt(10); } // Labels with gridLayout setLayout(new GridLayout(1, 4, 5, 5)); add(new JLabel(images[threeRandoms[0]])); } public void mouseClicked(MouseEvent e) { System.out.println("The frame was clicked."); new Cards(); } public void mouseEntered(MouseEvent e) { System.out.println("The mouse entered the frame."); } public void mouseExited(MouseEvent e) { System.out.println("The mouse exited the frame."); } public void mousePressed(MouseEvent e) { System.out.println("The left mouse button was pressed."); } public void mouseReleased(MouseEvent e) { System.out.println("The left mouse button was released."); } } 

Answer 1

对不起，我对你的代码感到困惑。 有一件事你的cards1() ， cards1()和cards3()方法看起来都是一样的，如果是这样，为什么有3种不同的方法呢？ 为什么不只是一种方法？ 在这些方法中，您似乎尝试重复添加JLabel。 您是否尝试向GUI添加许多JLabel？ 或者您只是想显示3个在鼠标操作中随机变化的图像？

我建议稍微改变一下结构：

• 如果可能，在类的构造函数中一次读取所有必需的图像，将图像放入ImageIcons，然后根据需要将它们添加到ArrayList或几个ArrayLists中。
• 每次发生鼠标单击时都不要添加新的JLabel。
• 创建一个JPanel，给它一个GridLayout，并在你的类构造函数中添加三个JLabel，它们是实例字段或数组或ArrayList。
• 将此JPanel添加到您的JFrame。
• 将MouseListener添加到每个JLabel
• 在MouseListener的mousePressed(MouseEvent e)方法（不是mouseClicked ）中随机化你的数字并使用该数字在JLabel源上调用setIcon(...) ，通过在MouseEvent参数上调用getSource()获得。

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例如：

 import java.awt.GridLayout; import java.awt.event.MouseAdapter; import java.awt.event.MouseEvent; import java.util.ArrayList; import java.util.List; import java.util.Random; import javax.swing.*; @SuppressWarnings("serial") public class RandomImages extends JPanel { private static final int LABEL_COUNT = 3; private Random random = new Random(); public RandomImages() { setLayout(new GridLayout(1, 3)); for (int i = 0; i < LABEL_COUNT; i++) { final List iconList = new ArrayList<>(); // TODO: get images for the ith list // and fill iconList with ImageIcons from the first grouping // create JLabel and give it the first Icon from the List above final JLabel label = new JLabel(iconList.get(0)); label.addMouseListener(new MouseAdapter() { @Override public void mousePressed(MouseEvent e) { // get random number from random object using iconList.size() // get random Icon from list // set label's icon via setIcon(...) } }); // add to GUI add(label); } } private static void createAndShowGui() { JFrame frame = new JFrame("RandomImages"); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.getContentPane().add(new RandomImages()); frame.pack(); frame.setLocationRelativeTo(null); frame.setVisible(true); } public static void main(String[] args) { SwingUtilities.invokeLater(new Runnable() { public void run() { createAndShowGui(); } }); } } 

具体例子2：

 import java.awt.GridLayout; import java.awt.event.MouseAdapter; import java.awt.event.MouseEvent; import java.awt.image.BufferedImage; import java.io.IOException; import java.net.URL; import java.util.ArrayList; import java.util.List; import java.util.Random; import javax.imageio.ImageIO; import javax.swing.*; @SuppressWarnings("serial") public class RandomChessMen extends JPanel { // for this example I get a sprite sheet that holds several sprite images in it // the images can be found here: http://stackoverflow.com/questions/19209650 private static final String IMAGE_PATH = "http://sofzh.miximages.com/java/memI0.png"; private static final int LABEL_COUNT = 2; private static final int ICON_COLUMNS = 6; private Random random = new Random(); public RandomChessMen() throws IOException { URL url = new URL(IMAGE_PATH); BufferedImage largeImg = ImageIO.read(url); setLayout(new GridLayout(1, 0)); // break down large image into its constituent sprites and place into ArrayList int w = largeImg.getWidth() / ICON_COLUMNS; int h = largeImg.getHeight() / LABEL_COUNT; for (int i = 0; i < LABEL_COUNT; i++) { final List iconList = new ArrayList<>(); int y = (i * largeImg.getHeight()) / LABEL_COUNT; // get 6 icons out of large image for (int j = 0; j < ICON_COLUMNS; j++) { int x = (j * largeImg.getWidth()) / ICON_COLUMNS; // get subImage BufferedImage subImg = largeImg.getSubimage(x, y, w, h); // create ImageIcon and add to list iconList.add(new ImageIcon(subImg)); } // create JLabel final JLabel label = new JLabel("", SwingConstants.CENTER); int eb = 40; label.setBorder(BorderFactory.createEmptyBorder(eb, eb, eb, eb)); // get random index for iconList int randomIndex = random.nextInt(iconList.size()); Icon icon = iconList.get(randomIndex); // use index to get random Icon label.setIcon(icon); // set label's icon label.addMouseListener(new MouseAdapter() { @Override public void mousePressed(MouseEvent e) { Icon secondIcon = label.getIcon(); // so we don't repeat icons while (label.getIcon() == secondIcon) { int randomIndex = random.nextInt(iconList.size()); secondIcon = iconList.get(randomIndex); } label.setIcon(secondIcon); } }); // add to GUI add(label); } } private static void createAndShowGui() { JFrame frame = new JFrame("RandomImages"); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); try { frame.getContentPane().add(new RandomChessMen()); } catch (IOException e) { e.printStackTrace(); System.exit(-1); } frame.pack(); frame.setLocationRelativeTo(null); frame.setVisible(true); } public static void main(String[] args) { SwingUtilities.invokeLater(new Runnable() { public void run() { createAndShowGui(); } }); } } 

Answer 2

我对您的代码进行了以下更改：

• 而不是有三种方法cards1() cards2() cards3() ，我刚刚制作了一种cards()方法。
• 每次单击框架时，都会加载三个随机图像。
• 我已经在JLabel中设置了每个图像，以便于更新它。

以下代码可根据您的需求完美运行。

 package example; import java.awt.Color; import java.awt.Dimension; import java.awt.GridLayout; import java.awt.event.MouseEvent; import java.awt.event.MouseListener; import java.util.Random; import javax.swing.ImageIcon; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JPanel; import javax.swing.SwingConstants; import javax.swing.SwingUtilities; public class Cards extends JFrame implements MouseListener { JPanel subPanel1; JLabel label1, label2, label3; static ImageIcon[] images ; static Random ran ; static int[] threeRandoms; public Cards() { super("Cards"); subPanel1 = new JPanel(); // Set up first subpanel subPanel1.setPreferredSize (new Dimension(400, 400)); //subPanel1.setBackground (Color.cyan); label1 = new JLabel ("image 1",SwingConstants.CENTER); label2 = new JLabel ("image 2", SwingConstants.LEFT); label3 = new JLabel ("image 3", SwingConstants.CENTER); subPanel1.add (label1); subPanel1.add (label2); subPanel1.add (label3); add(subPanel1); addMouseListener(this); setSize(500, 500); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); pack(); setLocationRelativeTo(null); setVisible(true); System.out.println("Success....."); } public void cards() { for (int i = 0; i < threeRandoms.length; i++) threeRandoms[i] = ran.nextInt(3); label1.setIcon(images[threeRandoms[0]]); label2.setIcon(images[threeRandoms[1]]); label3.setIcon(images[threeRandoms[2]]); } @Override public void mouseClicked(MouseEvent e) { System.out.println("mouseClicked"); cards(); } @Override public void mouseEntered(MouseEvent e) { System.out.println("mouseEntered"); } @Override public void mouseExited(MouseEvent e) { System.out.println("mouseExited"); } @Override public void mousePressed(MouseEvent e) { System.out.println("mousePressed"); } @Override public void mouseReleased(MouseEvent e) { System.out.println("mouseReleased"); } public static void loadImages(){ images = new ImageIcon[4]; ran = new Random(); threeRandoms = new int[3]; for (int i = 1; i <= images.length; i++) { images[i-1] = new ImageIcon("Drawables//Images//" + i + ".png"); } } public static void main(String[] args) { loadImages(); SwingUtilities.invokeLater(new Runnable() { public void run() { new Cards(); } }); } }