How to do conditional polling in primefaces? - primefaces

Question

I want to do conditional Polling in Primefaces (Version:6.0.0).
Here is the polling code:
<p:poll interval="20" update="liveChart,chrtTC_Cnt_Status,chrtStatus" />
For Example, I am field call Status. If status value is 'In-Progress' then only polling should start. Or else it should not do polling.
Here is my field code, if this value changed to 'In-Progress' then polling should start or else not
<p:outputLabel value="Status:" />
<p:outputLabel id="lblCurrentStatus" value="#{backingBean.status}" />
Here is my Xhtml code
<h:panelGrid columns="2" width="400">
<p:outputLabel for="lblStudentName" value="Select Other StudentName: " />
<p:selectOneMenu id="lblStudentName" style="width:250px"
value="#{backingBean.selectedStudent}"
panelStyle="width:180px" effect="fade" filter="true"
filterMatchMode="startsWith">
<f:selectItem itemLabel="Select One" itemValue=""
noSelectionOption="true" />
<f:selectItems value="#{backingBean.studentItemList}" />
<p:ajax
listener="#{backingBean.OnChangeOtherStudentDropDown}"
update=":idForm:tabStatus:p1,:idForm:tabStatus:p4,growl"
process="#form" />
</p:selectOneMenu>
<p:tabView id="tabStatus">
<p:tab title="Status" id="idStatusTab">
<h:panelGrid columns="3" cellpadding="10" id="p1">
<p:growl id="growl" showDetail="true" />
<p:ajaxStatus onstart="PF('statusDialog').show()"
onsuccess="PF('statusDialog').hide()" />
<p:dialog widgetVar="statusDialog" draggable="false"
closable="false" resizable="false" showHeader="false">
<h:graphicImage value="/images/ajax-loader.gif" />
</p:dialog>
<h:panelGrid columns="2" cellpadding="5" id="p2">
<p:outputLabel value="Failed:" />
<p:outputLabel id="lblCurrentFailed"
value="#{backingBean.intCurrentFailedStudent}" />
<p:outputLabel value="Processed:" />
<p:outputLabel id="lblCurrentProcess"
value="#{backingBean.intCurrentPassedStudent}" />
<p:outputLabel value="Status:" />
<p:outputLabel id="lblCurrentStatus"
value="#{backingBean.status}" />
</h:panelGrid>
<h:panelGrid columns="2" cellpadding="10" id="p3">
<p:chart type="pie" model="#{backingBean.pieModel1}"
rendered="#{not empty backingBean.pieModel1}"
id="chrtStatus" style="width:300px;height:200px">
</p:chart>
<br />
</h:panelGrid>
</h:panelGrid>
<h:panelGrid columns="3" cellpadding="10" id="p4">
<p:poll interval="20" update="liveChart,chrtTC_Cnt_Status,chrtStatus" />
<p:chart type="line"
model="#{backingBean.lineCurrentLineChart}"
rendered="#{not empty backingBean.lineCurrentLineChart}"
id="liveChart" style="height:500px;width:500px" />
<p:chart type="bar"
model="#{backingBean.barStatusCountStudent}"
rendered="#{not empty backingBean.barStatusCountStudent}"
id="chrtTC_Cnt_Status" style="width:500px;height:500px">
<p:ajax event="itemSelect" listener="#{backingBean.itemSelect}" />
</p:chart>
</h:panelGrid>
</p:tab>
</p:tabView>
</h:form>

Answer 1

Solution 1:
Wrap your p:poll within h:panelGroup or h:panelGrid, set rendered="#{backingBean.status eq 'In-Progress'}" on panel and update panel on changing of status, that will reset your polling.
Solution 2:
If you want to manually start and stop the polling then you need to set autoStart="false" and add widgetVar="statusPoll" attributes on p:poll and by invoking PF('statusPoll').start(); and PF('statusPoll').stop(); on changing the value of status field.

Answer 2

It is working,
<h:panelGrid columns="1" id="ID_polling" rendered="#{BackingBean.status eq 'In-Progress'}">
<p:poll interval="20" update="liveChart,chrtTC_Cnt_Status,chrtStatus" />
</h:panelGrid>
When I write this Panel, Panel will display only when status = 'In-Progress' or else it will not display.
Thank you again,