Name: rlT66838 Date: 07/30/97


It appears as if JDK 1.1.3 has trouble calculating
the correct Insets for a Frame if that Frame
contains a MenuBar. This makes it working with
LayoutManagers particularly troublesome.

The following app displays a Frame containing three
buttons. The Insets for the Frame are reported as
[t=23,l=4,b=4,r=4] which effectively results in a
4-pixel border around the window.


import java.awt.*;

public class TestApp1 extends Frame {

  public TestApp1()
  {
    setLayout(new FlowLayout());

    add(new Button("One"));
    add(new Button("Two"));
    add(new Button("Three"));

    pack();
    System.out.println(this.getInsets());
  }

  public static void main(String[] args)
  {
    TestApp1 app = new TestApp1();
    app.show();
  }
}

The following application adds a simple MenuBar to
the application above. When the MenuBar is added,
the Insets for the Frame are reported as [42,4,-15,4]
which causes the LayoutManager to position the
buttons so that they are not completely visible!


import java.awt.*;
import java.awt.event.*;

public class TestApp2 extends Frame {

  public TestApp2()
  {
    setLayout(new FlowLayout());

    MenuBar mbar = new MenuBar();
    Menu file = new Menu("File");
    mbar.add(file);

    MenuItem quit = new MenuItem("Quit", new MenuShortcut(KeyEvent.VK_Q));
    quit.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent e) { System.exit(0);}
    });
    file.add(quit);
    
    setMenuBar(mbar);

    add(new Button("One"));
    add(new Button("Two"));
    add(new Button("Three"));

    pack();
    System.out.println(this.getInsets());
  }

  public static void main(String[] args)
  {
    TestApp2 app = new TestApp2();
    app.show();
  }
}


One might also argue that the default Insets for
a Frame should provide a 0 pixel border around
the edge of the frame. This would allow clients
to draw across the entire Frame without having to
jump through any hoops...
company - Actioneer, Inc. , email - ###@###.###
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