Content of JInternalFrame packed too tightly

Question

When I call pack() on a JInternalFrame it is not packed correctly, mostly too tight.

Edit:

Here is a minimal example that shows the behavior described above. It also seems to depend on the used lookandfeel (here: Nimbus).

import javax.swing.*;

public class JInternalFrameTester {

  public static void main(String[] args) {
    try {
      UIManager.setLookAndFeel("com.sun.java.swing.plaf.nimbus.NimbusLookAndFeel");
    }
    catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
      System.err.println("Failed setting NimbusLookAndFeel");
    }
    JFrame frame = new JFrame();
    JDesktopPane desktop = new JDesktopPane();
    desktop.setOpaque(true);
    frame.setContentPane(desktop);
    frame.setSize(250, 250);
    frame.setVisible(true);

    JInternalFrame iframe = new JInternalFrame("Internal Frame");
    JTextField textfield = new JTextField("Any text here");
    iframe.add(textfield);
    iframe.setVisible(true);
    /* XXX If placed here, it crashes the layouts */
    iframe.pack();
    desktop.add(iframe);
    /* XXX If placed here, the layout is right */
    //iframe.pack();
  }
}

Answer 1

将JInternalFrame添加到相应的JDesktopPane 之后，必须调用pack() 。