如何在不使用 ComponentListener 或其他侦听器的情况下将 GlassPane 中的 JLabel 粘贴到来自 JProgressBar 的相对浮动坐标,
标准 LayoutManagers 中是否有内置通知器可以通知其内部状态,并且可以覆盖,而不是我尝试使用 ComponentListener 和 NullLayout
.
SSCCE 关于ComponentListener
和与NullLayout
import java.awt.Container;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.GridBagConstraints;
import java.awt.event.ComponentAdapter;
import java.awt.event.ComponentEvent;
import javax.swing.JButton;
import javax.swing.JCheckBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JProgressBar;
import javax.swing.JRadioButton;
import javax.swing.UIManager;
//http://stackoverflow.com/questions/14560680/jprogressbar-low-values-will-not-be-displayed
public class ProgressSample {
private JFrame frame = new JFrame("GlassPane instead of JLayer");
private JLabel label;
private GridBagConstraints gbc = new GridBagConstraints();
private JProgressBar progressSeven;
public ProgressSample() {
frame.setLayout(new FlowLayout());
frame.add(new JButton("test"));
frame.add(new JCheckBox("test"));
frame.add(new JRadioButton("test"));
// Nothing is displayed if value is lover that 6
JProgressBar progressSix = new JProgressBar(0, 100);
progressSix.setValue(2);
frame.add(progressSix);
// but this works value is higher that 6
progressSeven = new JProgressBar(0, 100);
progressSeven.addComponentListener(new ComponentAdapter() {
@Override
public void componentMoved(ComponentEvent e) {
label.setBounds(
(int) progressSeven.getBounds().getX(),
(int) progressSeven.getBounds().getY(),
progressSeven.getPreferredSize().width,
label.getPreferredSize().height);
}
});
progressSeven.setValue(7);
frame.add(progressSeven);
label = new JLabel();
label.setText("<html>Blablabla, Blablablabla<br>"
+ "Blablabla, Blablablabla<br>"
+ "Blablabla, Blablablabla</html>");
label.setPreferredSize(new Dimension(
progressSeven.getPreferredSize().width,
label.getPreferredSize().height));
Container glassPane = (Container) frame.getRootPane().getGlassPane();
glassPane.setVisible(true);
glassPane.setLayout(null);
glassPane.add(label, gbc);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (Exception e) {
e.printStackTrace();
}
ProgressSample dialogTest = new ProgressSample();
}
}