Name: skT88420 Date: 08/03/99


The problem is that if you programatically setVisible(false) on a JFrame on Win32, the focus is lost, ie. nothing has focus. Perhaps this is the desired behavior but I doubt it since this isn't what happens on Solaris. Moreover, once the focus is lost in this manner, if you press TAB without clicking on the visible frame, you get a NullPointerException.

Steps to reproduce the problem:
1. Run the code below.
2. Notice that the visible frame does not have focus.
3. Press TAB and get the following exception:

java.lang.NullPointerException:
at javax.swing.DefaultFocusManager.childrenTabOrder(DefaultFocusManager.java:347)
at javax.swing.DefaultFocusManager.tabOrderNextComponent(DefaultFocusManager.java:296)
at javax.swing.DefaultFocusManager.getComponentAfter(DefaultFocusManager.java:253)
at javax.swing.DefaultFocusManager.getNextComponent(DefaultFocusManager.java:184)
at javax.swing.DefaultFocusManager.getFocusableComponentAfter(DefaultFocusManager.java:158)
at javax.swing.DefaultFocusManager.focusNextComponent(DefaultFocusManager.java:90)
at javax.swing.DefaultFocusManager.processKeyEvent(DefaultFocusManager.java:75)
at javax.swing.JComponent.processKeyEvent(JComponent.java:1527)
at java.awt.Component.processEvent(Component.java:3008)
at java.awt.Container.processEvent(Container.java:990)
at java.awt.Component.dispatchEventImpl(Component.java:2394)
at java.awt.Container.dispatchEventImpl(Container.java:1035)
at java.awt.Component.dispatchEvent(Component.java:2307)
at java.awt.LightweightDispatcher.processKeyEvent(Container.java:1766)
at java.awt.LightweightDispatcher.dispatchEvent(Container.java:1740)
at java.awt.Container.dispatchEventImpl(Container.java:1022)
at java.awt.Window.dispatchEventImpl(Window.java:749)
at java.awt.Component.dispatchEvent(Component.java:2307)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:287)
at java.awt.EventDispatchThread.pumpOneEvent(EventDispatchThread.java:101)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:92)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:83)

-------------------- CODE BELOW -----------------------

import javax.swing.*;

public class FocusTest {

    public static void main(String[] args) {
final JFrame frame1 = new JFrame("Test 1");
final JFrame frame2 = new JFrame("Test 2");
frame1.setSize(200,200);
frame1.show();

SwingUtilities.invokeLater(new Runnable() {
public void run() {
frame2.setBounds(200,200,200,200);
frame2.show();
frame2.setVisible(false);
}
});
    }
    
}

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This is exhibited on WinNT 4.0 Service Pack 5 and on Win98.

The java version is JDK 1.2.2-W
(Review ID: 93404)
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