One Click Case Label Generation - Visualforce page

One Click Case Label Generation - Visualforce page.xml

<apex:page standardController="Case" extensions="NewShipmentCaseController" action="{! processBulkShipment }">
    <apex:form >
    	<apex:outputPanel id="blockId">
    		<apex:pageMessages escape="false"/>
	        <apex:image url="{! URLFOR($Resource.Spinner) }" rendered="{! startPoller }"/>
	        <apex:outputLink value="/{! caseId }" rendered="{! NOT(startPoller) }">Back to Case</apex:outputLink>
	        <apex:actionPoller action="{! checkBatchStatus }" reRender="blockId" interval="5"
	        	enabled="{!startPoller}"/>
    	</apex:outputPanel>
    </apex:form>
</apex:page>