The JRadioButton that is currently selected in the ButtonGroup set as the default focus component

• download example.jar
• download src.zip
• repository

Code

buttons.setFocusTraversalPolicyProvider(true);
buttons.setFocusTraversalPolicy(new LayoutFocusTraversalPolicy() {
  @Override public Component getDefaultComponent(Container focusCycleRoot) {
    ButtonModel selection = bg.getSelection();
    for (Component c: focusCycleRoot.getComponents()) {
      JRadioButton r = (JRadioButton) c;
      if (r.getModel().equals(selection)) {
        return r;
      }
    }
    return super.getDefaultComponent(focusCycleRoot);
  }
});

References

• [JDK-8033699] Incorrect radio button behavior - Java Bug System
• [JDK-8154043] Fields not reachable anymore by tab-key, because of new tabbing behaviour of radio button groups. - Java Bug System
• java - Get the focus in a ButtonGroup of JRadioButtons to go to the currently selected item instead of first - Stack Overflow
• The JRadioButton that is currently selected in the ButtonGroup set as the default focus component (Japanese)