Get value from another Window Modal and fill in textbox

<?xml version="1.0" encoding="UTF-8"?>
<?init class="org.zkoss.zkplus.databind.AnnotateDataBinderInit" root="./window1" ?>
<?variable-resolver class="org.zkoss.zkplus.spring.DelegatingVariableResolver"?>
<zk xmlns="http://www.zkoss.org/2005/zul"                                       xmlns:h="http://www.w3.org/1999/xhtml"
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"   xsi:schemaLocation="http://www.zkoss.org/2005/zul
       http://www.zkoss.org/2005/zul/zul.xsd">

<zscript>
<![CDATA[
    import controller.window1Controller;
    import controller.window2Controller;
]]>
</zscript>

    <window id="window1t" width="650px"   title="Input" border="normal" apply="${Window1Controller}">
        <textbox id="txtDisc" /> <!-- I wan fill this textboxt from window2 
        <button id="btnShowWindow2"   label="Show Window2" forward="onClick=onBtnClick(evt)" />

    </window>
</zk>

@org.springframework.stereotype.Component("Window1Controller")
@Scope("prototype")
public class Window1Controller extends GenericForwardComposer {

@Override
    public void doAfterCompose(Component comp) throws Exception {
        super.doAfterCompose(comp);
   }

 public void onBtnClick(Event evt) {
       try {

              //show window2
            Executions.createComponents("/WEB-INF/zk/Windows2.zul",window1,null);

        } catch (Exception ex) {
            ex.printStackTrace();
         }
    }
}

<?xml version="1.0" encoding="UTF-8"?>
<?init class="org.zkoss.zkplus.databind.AnnotateDataBinderInit" root="./window2" ?>
<?variable-resolver class="org.zkoss.zkplus.spring.DelegatingVariableResolver"?>

<zk xmlns="http://www.zkoss.org/2005/zul"
    xmlns:h="http://www.w3.org/1999/xhtml"  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://www.zkoss.org/2005/zul  http://www.zkoss.org/2005/zul/zul.xsd">


    <zscript>
<![CDATA[
    import controller.Windows2Controller;
    ]]>
    </zscript>

    <window id="window2 title="List" border="normal" width="400px"  height="450px" closable="true"
        mode="modal" apply="${Window2Controller"}>


            <div>
                <button id="btnClose"   label="Close"  forward="onClick=onClickClose(evt)" />
            </div>

        </window>
    </zk>

@org.springframework.stereotype.Component("Window2Controller")
@Scope("prototype")
public class Window2Controller extends GenericForwardComposer {

    //close window2
    public void onClickClose(Event evt) {
     
      String typeDisc="InternalDisc"; //this value i want send to Window1, and fill in textbox txtDisc
                                                              //when this window close
      
       Window window2=(Window) evt.getTarget();
       window2.detach();

    }
}