reset primefaces calendar date to system date - jsf

Question

I am designing a page technology using jsf 2.0 and primefaces. In my page I insert a prime faces calendar. When the user click on calendar to change the default date, a warning message shown which is a dialog box containing two command button. Now what I am trying to do is when the user click on cancel command button, the date should be changed back to the default date which was populated from the first time page when the page loaded. I wrote a java script but its not working.
<label>Date<label>
<p:calendar readonlyInput="true" widgetVar="calDate" yearRange="c-20:c+20" navigator="true" id="b1incomeeffectfrom#{incmStatus.index}" value="#{userDate.effectiveFrom}" pattern="dd/mm/yyyy">
<p:ajax event="dateSelect" oncomplete="checkForDefault(this);" global="false"/>
</p:calendar>
<p:dialog rendered="#{user.Lock}" widgetVar="dlg1" header="Warning" modal="true">
<h:panelGroup layout="block" styleClass="modal-dialog">
<h:panelGroup layout="block" styleClass="modal-content">
<h:panelGroup layout="block" styleClass="modal-body">
<div class="form-horizontal">
<h:panelGroup layout="block" styleClass="form-group">
<h:outputLabel styleClass="col-xs-8 control-label">Are you sure want to change?</h:outputLabel>
</h:panelGroup>
</div>
</h:panelGroup>
<h:panelGroup layout="block" styleClass="modal-footer">
<p:commandButton value="Ok" type="button" styleClass="btn btn-primary" onclick="PF('dlg1').hide();PF('dlg2').show();" />
<p:commandButton value="Cancel" type="button" styleClass="btn btn-primary" onclick="resetDate();" />
</h:panelGroup>
</h:panelGroup>
</h:panelGroup>
</p:dialog>
javascript
function resetDate(){
PF('dlg1').hide();
calDate.setDate(null);
}

Answer 1

Your calendar value is coming from your backing bean (userDate.effectiveFrom). You will have to change the value there to take effect
<p:commandButton value="Cancel" type="button" styleClass="btn btn-primary"
onsuccess="PF('dlg1').hide()" action="#{userDate.resetDate()}" update="calDate" />
class UserDate{
[..]
public void resetDate(){
this.effectiveFrom = initialDate;
}
[..]
}