我正在尝试制作一个仅包含单个标签的弹出窗口。理想情况下，我会指定弹出窗口的最大宽度和要显示的字符串，并且弹出窗口会自动调整自身大小，以便文本在超过指定的最大宽度时会换行，并且它将是正确的高度。如果不使用复杂的 FontMetrics 来暴力计算，在 Swing 中是否可以做到这样的事情？这是我正在尝试做的一个示例:
import java.awt.Color;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.FlowLayout;
import java.awt.Point;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.Popup;
import javax.swing.PopupFactory;
import javax.swing.SpringLayout;
public class PopupTest extends JFrame {
private static final String FOX_MESSAGE = "<html>The lithe, quick, brown fox jumps " +
"happily and steadily over the fat, slobbery, " +
"lazy dogs</html>";
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
PopupTest frame = new PopupTest();
frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
public PopupTest() {
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setBounds(100, 100, 450, 300);
final JPanel contentPane = new JPanel();
setContentPane(contentPane);
contentPane.setLayout(new FlowLayout(FlowLayout.CENTER, 5, 5));
final JButton btnLaunch = new JButton("Launch popup");
btnLaunch.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
Point btnLoc = btnLaunch.getLocationOnScreen();
FoxPopup popup = new FoxPopup(FOX_MESSAGE, 200);
popup.launch(contentPane, btnLoc.x, btnLoc.y + btnLaunch.getHeight());
}
});
contentPane.add(btnLaunch);
}
public class FoxPopup extends JPanel {
private static final int ARBITRARILY_TALL = 9999;
private Popup popup;
public FoxPopup(String message, int width) {
setBackground(Color.pink);
// SpringLayout springLayout = new SpringLayout();
// setLayout(springLayout);
JLabel lblDescription = new JLabel(message);
// springLayout.putConstraint(SpringLayout.NORTH, lblDescription, 5, SpringLayout.NORTH, this);
// springLayout.putConstraint(SpringLayout.WEST, lblDescription, 5, SpringLayout.WEST, this);
// springLayout.putConstraint(SpringLayout.EAST, lblDescription, -5, SpringLayout.EAST, this);
add(lblDescription);
// setPreferredSize(new Dimension(width, 65));
setMaximumSize(new Dimension(width, ARBITRARILY_TALL));
}
public void launch(Component owner, int x, int y) {
popup = PopupFactory.getSharedInstance().getPopup(owner, this, x, y);
popup.show();
}
}
}
如果我编译并运行上面的代码，那么我会得到一个宽弹出窗口(比我请求的最大 200 像素更宽)，所有文本都在一行上。如果我取消注释所有注释行，那么我会得到所需的行为，但我必须在 setPreferredSize() 调用中指定宽度和高度，所以它是处理不同输入消息的鲁棒性不强。
根据下面 Andrew Thompson 的答案编辑解决方案
public class PopupTest extends JFrame {
private static final String FOX_MESSAGE = "The lithe, quick, brown fox jumps " +
"happily and steadily over the fat, slobbery, " +
"lazy dogs";
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
PopupTest frame = new PopupTest();
frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
public PopupTest() {
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setBounds(100, 100, 450, 300);
final JPanel contentPane = new JPanel();
setContentPane(contentPane);
contentPane.setLayout(new FlowLayout(FlowLayout.CENTER, 5, 5));
final JButton btnLaunch = new JButton("Launch popup");
btnLaunch.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
Point btnLoc = btnLaunch.getLocationOnScreen();
FoxPopup popup = new FoxPopup(FOX_MESSAGE, 200);
popup.launch(contentPane, btnLoc.x, btnLoc.y + btnLaunch.getHeight());
}
});
contentPane.add(btnLaunch);
}
public static class FoxPopup extends JPanel {
private Popup popup;
public FoxPopup(String message, int width) {
setBackground(Color.pink);
JLabel lblDescription = new JLabel(formatMessage(message, width));
add(lblDescription);
}
private static String formatMessage(String message, int width) {
return String.format("<html><body style='width: %d'>%s</body></html>", width, message);
}
public void launch(Component owner, int x, int y) {
popup = PopupFactory.getSharedInstance().getPopup(owner, this, x, y);
popup.show();
}
}
}
最佳答案
参见FixedWidthText它使用 CSS 来固定宽度:
关于java - 如何制作带有换行文本的自动调整大小的 Swing 弹出窗口？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/25266847/