p:dialog appears on bottom when p:blockUI targets it - jsf

Question

I have a PrimeFaces dialog, that has two command buttons that executes some code in the backing bean. I want to block the dialog within the action.
I managed to do it using blockUI, but when the blockUI is present, and I open the dialog, it appears at the bottom of the page.
If I remove the blockUI component, the dialog opens at the center of the page, as I want. But I want it to be centered and with the blockUI.
<p:dialog header="Attention" id="dialog" position="center"
widgetVar="dialog" modal="true" closable="false"
dynamic="true" closeOnEscape="false">
<div class="internal-margin-top">
<h:outputText value="Location" styleClass="ui-outputtext" />
<p:inputText value="#{activityBean.location}"
id="inputLocation" maxlength="15">
</p:inputText>
</div>
<div class="internal-margin-bottom">
<p:commandButton id="closureYes" value="Yes"
styleClass="btn-green"
onstart="PF('block').show();"
oncomplete="PF('dialog').hide(); PF('block').hide();"
action="#{activityBean.processItem()}" process="#all">
</p:commandButton>
<p:commandButton id="closureNo" value="No"
styleClass="btn-red"
onstart="PF('block').show();"
oncomplete="PF('dialog').hide(); PF('block').hide();"
action="#{activityBean.processActivity()}" process="#all" />
</div>
</p:dialog>
<p:blockUI block="scrapDialog" widgetVar="block">
<p:graphicImage library="images" name="loading_bar.gif" />
</p:blockUI>
Thanks in advance.

Answer 1

Example with a centered modal dialog:
<p:dialog header="Header" position="center" widgetVar="wv_dialog" modal="true" closable="false" dynamic="true" closeOnEscape="false">
<h:form id="dialogform">
<p:panelGrid columns="1">
<p:inputText value="test"/>
<p:inputText value="test"/>
<p:inputText value="test"/>
<p:inputText value="test"/>
</p:panelGrid>
<p:commandButton id="closebutton"
value="Close"
oncomplete="PF('wv_dialog').hide();"
action="#{testBean.actionTest()}"
process="#form"/>
<p:blockUI block="dialogform" trigger="closebutton"/>
</h:form>
</p:dialog>