a problem for use p:print

[darkcloud8027]

I try to print some components in my page by using p:print

could somebody tell me how to identify a component id in a page.
my code as following. but when I run it, then throw error

<h:panelGrid columns="2" style="width:600px" >
<h:panelGroup>
............
</h:panelGroup>
<h:panelGroup>
<h:commandButton id="btn" value="Print">
<p:printer target="dataPic" />
</h:commandButton>
</h:panelGroup>
</h:panelGroup>

<h:panelGrid id="chartPanel" columns="2" style="width:900px">
<p:graphicImage id="dataPic" value="#{wealthBean.displinechart}" />
</h:panelGroup>
....

[cagatay.civici]

What is the error you are getting?

[darkcloud8027]

cannot find dicPic

[darkcloud8027]

cannot find id dataPic

[cagatay.civici]

Can't replicate the issue.