Java 如何使用image fill BorderLayout.CENTER制作JLabel
我得到了一个JFrame并将LayoutManager设置为BorderLayout，然后继续添加带有图像的JLabel。但是，当我调整帧的大小时，JLabel不会调整大小。我没有向North、S、E等添加任何组件。我只是想让标签里的图像填满整个画面，当然，让我的菜单保持得体。请原谅我的傲慢，但我没有别的事情要做 我做了一个快速样品 查看图像周围的红线，这是Java 如何使用image fill BorderLayout.CENTER制作JLabel,java,swing,Java,Swing,我得到了一个JFrame并将LayoutManager设置为BorderLayout，然后继续添加带有图像的JLabel。但是，当我调整帧的大小时，JLabel不会调整大小。我没有向North、S、E等添加任何组件。我只是想让标签里的图像填满整个画面，当然，让我的菜单保持得体。请原谅我的傲慢，但我没有别的事情要做 我做了一个快速样品 查看图像周围的红线，这是JLabel的边框。如您所见，标签已重新调整大小以填充整个区域 这是我用来生成示例的代码 public class LayoutFram
JLabelpublic class LayoutFrame extends JFrame {
public LayoutFrame() throws HeadlessException {
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
Image image = null;
URL url = getClass().getResource("/layout/issue78.jpg");
try {
image = ImageIO.read(url);
} catch (IOException ex) {
ex.printStackTrace();
}
JLabel label = new JLabel(new ImageIcon(image));
label.setHorizontalAlignment(JLabel.CENTER);
label.setVerticalAlignment(JLabel.CENTER);
label.setBorder(new LineBorder(Color.RED, 4));
setLayout(new BorderLayout());
add(label);
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException ex) {
} catch (InstantiationException ex) {
} catch (IllegalAccessException ex) {
} catch (UnsupportedLookAndFeelException ex) {
}
LayoutFrame frame = new LayoutFrame();
frame.setSize(200, 200);
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
});
}
}
public class ImagePane extends JPanel {
protected static final Object RESIZE_LOCK = new Object();
private BufferedImage image;
private BufferedImage scaledImage;
private Timer resizeTimer;
public ImagePane() {
URL url = getClass().getResource("/layout/issue78.jpg");
try {
image = ImageIO.read(url);
} catch (IOException ex) {
ex.printStackTrace();
}
resizeTimer = new Timer(250, new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
// Simple thread factory to start a slightly lower
// priority thread.
CoreThreadFactory.getUIInstance().execute(new ResizeTask());
}
});
resizeTimer.setCoalesce(true);
resizeTimer.setRepeats(false);
}
@Override
public void setBounds(int x, int y, int width, int height) {
super.setBounds(x, y, width, height);
resizeTimer.restart();
}
@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g;
if (scaledImage != null) {
// This simply returns a rectangle that takes into consideration
//the containers insets
Rectangle safeBounds = UIUtilities.getSafeBounds(this);
System.out.println("scaledImage = " + scaledImage.getWidth() + "x" + scaledImage.getWidth());
int x = ((safeBounds.width - scaledImage.getWidth()) / 2) + safeBounds.x;
int y = ((safeBounds.height - scaledImage.getHeight()) / 2) + safeBounds.y;
g2d.drawImage(scaledImage, x, y, this);
}
}
protected class ResizeTask implements Runnable {
@Override
public void run() {
synchronized (RESIZE_LOCK) {
if (image != null) {
int width = getWidth();
int height = getHeight();
System.out.println("width = " + width);
System.out.println("height = " + height);
// A simple divide and conquer resize implementation
// this will scale the image so that it will fit within
// the supplied bounds
scaledImage = ImageUtilities.getScaledInstanceToFit(image, new Dimension(width, height), ImageUtilities.RenderQuality.High);
System.out.println("scaledImage = " + scaledImage.getWidth() + "x" + scaledImage.getWidth());
repaint(); // this is one of the few thread safe calls
}
}
}
}
}
最好的选择是对ImageIcon进行子类化，并覆盖其paintIcon方法，以便使用Graphics.paint（x、y、width、height…）简单地绘制图像。我希望所讨论的图像足够大，能够占用空间。请看一看，是的，图像足够大，不是一个小图标或任何东西。标签的图标不调整大小；）thanx代表样品。它的问题是它接管了一切，其他组件丢失了，比如菜单。你是对的，我的问题是标签没有调整其中的图标大小。这不应该影响你的菜单：P@trashgod不知道OP的知识水平，我不想听起来像是居高临下，但我不知道尝试了什么，所以我别无选择，只能从基础开始：可以说图标的非法实现：getIconWidth/Height被记录为返回一个指定图标固定宽度的整数-动态调整大小是不可能的…我想你最好使用某种
工厂图标图标