我一直在努力解决这个问题，我可以通过一般的主动监听器来切换图片，但是无法选择可点击区域的区域以允许切换。我希望创建一个带有边界的矩形，这将允许我有一个可点击区域来更改图片。我试图这样做但不确定如何设置一个动作监听器在jpanel的特定区域工作。任何帮助将不胜感激，谢谢！
public class drawPictures {
Random random = new Random();
int one = random.nextInt(1200)+1;
int two = random.nextInt(600)+1;
public static void main(String[] args) {
new drawPictures();
}
public drawPictures() {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
frame.add(new ImageViewPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class ImageViewPane extends JPanel {
private ImagePane imagePane;
private File[] fileList;
private int currentIndex = -1;
public ImageViewPane() {
fileList = new File("/Di/rec/tory").listFiles(new FileFilter() {
@Override
public boolean accept(File pathname) {
return pathname.isFile();
}
});
imagePane = new ImagePane();
imagePane.addMouseListener(new MouseAdapter() {
@Override
public void mouseClicked(MouseEvent e) {
Rectangle bounds = new Rectangle(one, two, 100, 100);
if (bounds.contains((e).getPoint())){
// Image was clicked...
currentIndex++;
if (currentIndex >= fileList.length) {
currentIndex = 0;
}
nextImage();
}
setLayout(new GridBagLayout());
add(imagePane);
nextImage();
}});}
public void nextImage() {
if (fileList != null && fileList.length > 0) {
currentIndex++;
if (currentIndex < 0 || currentIndex >= fileList.length) {
currentIndex = 0;
}
Image image = null;
/*
Because I don't know the contents of the folder, this is a little
more complicated then it really needs to be.
If you know the file is an image, you can simply use ImageIO.read(file)
*/
while (image == null && currentIndex < fileList.length) {
System.out.println("Loading next image: " + currentIndex);
try {
ImageInputStream iis = ImageIO.createImageInputStream(fileList[currentIndex]);
if (iis != null) {
Iterator<ImageReader> imageReaders = ImageIO.getImageReaders(iis);
if (imageReaders != null && imageReaders.hasNext()) {
ImageReader imageReader = imageReaders.next();
imageReader.setInput(iis);
image = imageReader.read(0);
} else {
currentIndex++;
}
} else {
currentIndex++;
}
} catch (Exception e) {
e.printStackTrace();
currentIndex++;
}
}
imagePane.setImage(image);
invalidate();
repaint();
}
}
}
public class ImagePane extends JPanel {
private Image image;
private JLabel label;
public ImagePane() {
setLayout(new GridBagLayout());
label = new JLabel("No image available");
add(label);
}
public void setImage(Image value) {``
if (image != value) {
image = value;
label.setVisible(image == null);
repaint();
}
}
@Override
public Dimension getPreferredSize() {
return image == null ? super.getPreferredSize() : new Dimension(image.getWidth(this)+140, image.getHeight(this)+200);
}
@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
if (image != null) {
int width = getWidth();
int height = getHeight();
int x = (width - image.getWidth(this)) / 2 -500 + one;
int y = (height - image.getHeight(this)) / 2- 300 + two;
g.drawImage(image, x, y, this);
}
}
}
}
答案 0 :(得分：2)
让我们从显而易见的事情开始......
你从未真正将ImagePane添加到任何内容中（首先，您尝试在点击后添加它，但如果它没有被添加到任何内容，它会如何被点击？）
//...
public ImageViewPane() {
//...
imagePane = new ImagePane();
imagePane.addMouseListener(new MouseAdapter() {
@Override
public void mouseClicked(MouseEvent e) {
//...
}
});
// And... nothing
}
你的MouseListener中有很多事情真的不需要在那里......
imagePane.addMouseListener(new MouseAdapter() {
@Override
public void mouseClicked(MouseEvent e) {
Rectangle bounds = new Rectangle(one, two, 100, 100);
if (bounds.contains((e).getPoint())) {
// Image was clicked...
currentIndex++;
if (currentIndex >= fileList.length) {
currentIndex = 0;
}
nextImage();
}
setLayout(new GridBagLayout());
add(imagePane);
nextImage();
}
});
您的来电nextImage至少一次，如果不是两次。一旦用户在您的可访问框内单击一次，并在方法结束时单击一次。尽管currentIndex无论如何都会这样做，但您也在递增nextImage值。您似乎也尝试将imagePane添加到容器中......再次...
这可以简化为......
imagePane.addMouseListener(new MouseAdapter() {
@Override
public void mouseClicked(MouseEvent e) {
Rectangle bounds = new Rectangle(one, two, 100, 100);
if (bounds.contains((e).getPoint())) {
// Image was clicked...
nextImage();
}
}
});
接下来，您的nextImage方法......
public void nextImage() {
if (fileList != null && fileList.length > 0) {
currentIndex++;
if (currentIndex < 0 || currentIndex >= fileList.length) {
currentIndex = 0;
}
Image image = null;
/*
Because I don't know the contents of the folder, this is a little
more complicated then it really needs to be.
If you know the file is an image, you can simply use ImageIO.read(file)
*/
while (image == null && currentIndex < fileList.length) {
System.out.println("Loading next image: " + currentIndex);
try {
ImageInputStream iis = ImageIO.createImageInputStream(fileList[currentIndex]);
if (iis != null) {
Iterator<ImageReader> imageReaders = ImageIO.getImageReaders(iis);
if (imageReaders != null && imageReaders.hasNext()) {
ImageReader imageReader = imageReaders.next();
imageReader.setInput(iis);
image = imageReader.read(0);
} else {
currentIndex++;
}
} else {
currentIndex++;
}
} catch (Exception e) {
e.printStackTrace();
currentIndex++;
}
}
imagePane.setImage(image);
invalidate();
repaint();
}
}
好的，这实际上并不坏，通过过滤掉那些你知道不是文件的文件，可以简化阅读图像的“绒毛”
fileList = new File("/a/directory/somewhere").listFiles(new FileFilter() {
@Override
public boolean accept(File pathname) {
return pathname.isFile()
&& (pathname.getName().toLowerCase().endsWith(".jpg")
|| pathname.getName().toLowerCase().endsWith(".bmp")
|| pathname.getName().toLowerCase().endsWith(".png")
|| pathname.getName().toLowerCase().endsWith(".gif"));
}
});
让我们假装我们生活在一个扩展实际意义上的世界。你可以尝试在这里阅读图像，如果它不是图像，则丢弃它，但这是非常耗费时间......
这样可以让nextImage更像......
public void nextImage() {
if (fileList != null && fileList.length > 0) {
currentIndex++;
if (currentIndex < 0 || currentIndex >= fileList.length) {
currentIndex = 0;
}
try {
Image image = ImageIO.read(fileList[currentIndex]);
imagePane.setImage(image);
invalidate();
repaint();
} catch (IOException ex) {
ex.printStackTrace();
}
}
}
现在，就个人而言，我File中的List，File每次Image无法生成List，我会将其从@Override
public Dimension getPreferredSize() {
return new Dimension(1200, 600);
}
，但那就是我
最后添加，您还应该添加...
ImageViewPane到你的int x = (width - image.getWidth(this)) / 2 - 500 + one;
int y = (height - image.getHeight(this)) / 2 - 300 + two;
课程，这将允许你打包它周围的框架（我在测试过程中不断丢失我的“魔术”方块，因为窗口很小）
我不完全确定这是做什么......
int x = one + ((100 - image.getWidth(this)) / 2);
int y = two + ((100 - image.getHeight(this)) / 2);
但是，像是......
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.GridBagLayout;
import java.awt.Image;
import java.awt.Rectangle;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.io.File;
import java.io.FileFilter;
import java.io.IOException;
import java.util.Iterator;
import java.util.Random;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.imageio.ImageIO;
import javax.imageio.ImageReader;
import javax.imageio.stream.ImageInputStream;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class DrawPictures {
Random random = new Random();
int one = random.nextInt(1200) + 1;
int two = random.nextInt(600) + 1;
public static void main(String[] args) {
new DrawPictures();
}
public DrawPictures() {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
frame.add(new ImageViewPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class ImageViewPane extends JPanel {
private ImagePane imagePane;
private File[] fileList;
private int currentIndex = -1;
public ImageViewPane() {
fileList = new File("...").listFiles(new FileFilter() {
@Override
public boolean accept(File pathname) {
return pathname.isFile()
&& (pathname.getName().toLowerCase().endsWith(".jpg")
|| pathname.getName().toLowerCase().endsWith(".bmp")
|| pathname.getName().toLowerCase().endsWith(".png")
|| pathname.getName().toLowerCase().endsWith(".gif"));
}
});
imagePane = new ImagePane() {
@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.setColor(Color.BLACK);
g.drawRect(one, two, 100, 100);
}
};
imagePane.addMouseListener(new MouseAdapter() {
@Override
public void mouseClicked(MouseEvent e) {
Rectangle bounds = new Rectangle(one, two, 100, 100);
if (bounds.contains((e).getPoint())) {
// Image was clicked...
nextImage();
}
}
});
setLayout(new BorderLayout());
add(imagePane);
}
@Override
public Dimension getPreferredSize() {
return new Dimension(1200, 600);
}
public void nextImage() {
if (fileList != null && fileList.length > 0) {
currentIndex++;
if (currentIndex < 0 || currentIndex >= fileList.length) {
currentIndex = 0;
}
try {
Image image = ImageIO.read(fileList[currentIndex]);
imagePane.setImage(image);
invalidate();
repaint();
} catch (IOException ex) {
ex.printStackTrace();
}
}
}
}
public class ImagePane extends JPanel {
private Image image;
private JLabel label;
public ImagePane() {
setLayout(new GridBagLayout());
label = new JLabel("No image available");
add(label);
}
public void setImage(Image value) {
if (image != value) {
image = value;
label.setVisible(image == null);
repaint();
}
}
@Override
public Dimension getPreferredSize() {
return image == null ? super.getPreferredSize() : new Dimension(image.getWidth(this) + 140, image.getHeight(this) + 200);
}
@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
if (image != null) {
int width = getWidth();
int height = getHeight();
int x = one + ((100 - image.getWidth(this)) / 2);
int y = two + ((100 - image.getHeight(this)) / 2);
g.drawImage(image, x, y, this);
}
}
}
}
将允许您将图像置于“魔术”方块中心......
最后，因为一堆不符合上下文的代码很难恢复到位......
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Audio Tag</title>
</head>
<body>
<!--Before HTML5, Developer can add audio tag by Plug-in like FLASH. But HTML5 introduces an audio tag for embedded an audio media in a web page**strong text**-->
<audio controls="controls">
<source src="Allegro%20from%20Duet%20in%20C%20Major.mp3" type="audio/mp3">
</audio>
</body>
</html>