/**
* Overrides <code>JComponent.removeNotify</code> to check if this button is currently set as the
* default button on the <code>RootPane</code>, and if so, sets the <code>RootPane</code>'s
* default button to <code>null</code> to ensure the <code>RootPane</code> doesn't hold onto an
* invalid button reference.
*/
public void removeNotify() {
JRootPane root = SwingUtilities.getRootPane(this);
if (root != null && root.getDefaultButton() == this) {
root.setDefaultButton(null);
}
super.removeNotify();
}
/**
* If inputComponent is non-null, the focus is requested on that, otherwise request focus on the
* default value
*/
public void selectInitialValue(JOptionPane op) {
if (inputComponent != null) inputComponent.requestFocus();
else {
if (initialFocusComponent != null) initialFocusComponent.requestFocus();
if (initialFocusComponent instanceof JButton) {
JRootPane root = SwingUtilities.getRootPane(initialFocusComponent);
if (root != null) {
root.setDefaultButton((JButton) initialFocusComponent);
}
}
}
}
private static JPanel createPanel(JFrame frame) {
JPanel panel = new JPanel();
JButton button = new JButton("Button");
JButton button2 = new JButton("Button 2");
JButton button3 = new JButton("Button 3");
JRootPane root = frame.getRootPane();
root.setDefaultButton(button);
panel.add(button);
panel.add(button2);
panel.add(button3);
return panel;
}