+ * <p>A {@link Ext.form.FieldContainer field container} which has a specialized layout for arranging
+ * {@link Ext.form.field.Radio} controls into columns, and provides convenience {@link Ext.form.field.Field} methods
+ * for {@link #getValue getting}, {@link #setValue setting}, and {@link #validate validating} the group
+ * of radio buttons as a whole.</p>
+ * <p><b>Validation:</b> Individual radio buttons themselves have no default validation behavior, but
+ * sometimes you want to require a user to select one of a group of radios. RadioGroup
+ * allows this by setting the config <tt>{@link #allowBlank}:false</tt>; when the user does not check at
+ * one of the radio buttons, the entire group will be highlighted as invalid and the
+ * {@link #blankText error message} will be displayed according to the {@link #msgTarget} config.</p>
+ * <p><b>Layout:</b> The default layout for RadioGroup makes it easy to arrange the radio buttons into
+ * columns; see the {@link #columns} and {@link #vertical} config documentation for details. You may also
+ * use a completely different layout by setting the {@link #layout} to one of the other supported layout
+ * types; for instance you may wish to use a custom arrangement of hbox and vbox containers. In that case
+ * the Radio components at any depth will still be managed by the RadioGroup's validation.</p>
+ * <p>Example usage:</p>
+ * <pre><code>
+var myRadioGroup = new Ext.form.RadioGroup({
+ id: 'myGroup',
+ xtype: 'radiogroup',
+ fieldLabel: 'Single Column',
+ // Arrange radio buttons into three columns, distributed vertically
+ columns: 3,
+ vertical: true,
+ items: [
+ {boxLabel: 'Item 1', name: 'rb', inputValue: '1'},
+ {boxLabel: 'Item 2', name: 'rb', inputValue: '2', checked: true},
+ {boxLabel: 'Item 3', name: 'rb', inputValue: '3'}
+ {boxLabel: 'Item 4', name: 'rb', inputValue: '4'}
+ {boxLabel: 'Item 5', name: 'rb', inputValue: '5'}
+ {boxLabel: 'Item 6', name: 'rb', inputValue: '6'}
+ ]
+});
+ * </code></pre>