<zk>
<radiogroup id="group1">
<attribute name="onCheck"><![CDATA[
        Messagebox.show(group1.getSelectedItem().getLabel());
    ]]></attribute>
</radiogroup>
<div id="div"/>
<button label="click" >
    <attribute name="onClick"><![CDATA[
        div.getChildren().clear();
        
        Radio r = new Radio("1");
        r.setRadiogroup(group1);
        div.appendChild(r);
        r = new Radio("2");
        r.setRadiogroup(group1);
        div.appendChild(r);
        //group1.invalidate();
    ]]></attribute>
</button>
</zk>