<zk xmlns:w="client">
    <tabbox>
        <tabs>
            <tab w:onSelect='alert("select 1")'>Tab 1</tab>
            <tab w:onSelect='alert("select 2")'>Tab 2</tab>
        </tabs>
        <tabpanels>
            <tabpanel >
                <window title="test" border="normal" w:onShow='alert("show 1")' w:onClick='alert("click 1")'>
                    Main Window
                </window>
            </tabpanel>
            <tabpanel>
                <window title="test" border="normal" w:onShow='alert("show 2")' w:onClick='alert("click 2")'>
                    Main Window 2
                </window>              
            </tabpanel>
        </tabpanels>
    </tabbox>
</zk>

<window xmlns:w="http://www.zkoss.org/2005/zk/client">
    <button label="show" onClick="b1.setVisible(true);" />
    <button label="hide" onClick="b1.setVisible(false);" />
    <!--
    onShow is not called when first time rendering.
    It is called while setVisible="false", and then setVisible="true"   
    -->
    <button label="if onShow" id="b1"
        style="position:relative;zoom:1">
        <attribute w:name="onShow">
            alert("listened to onShow");
        </attribute>
        <attribute w:name="bind_">
            function () { this.$bind_(); zWatch.listen({onShow: this});}
        </attribute>
    </button>
</window>