Unable to hide primefaces blockui after pdf generation - jsf-2

Question

I am generating pdf and displaying it in separate window/tab using the approach described in The BalusC Code: PDF handling.I need to display blockui ajax loader when i select the commandlink to display pdf.The pdf gets generated but the ajax loader image remains as it is.I need to manually refresh the page to hide it.Is there any way using which it can be hidden as soon as the pdf gets displayed.
My code snippet is as below
JSF page
<h:form id="subFrm">
<p:commandLink value="Download PDF" action="#{pdfBean.downloadPDF}"
onclick="blkUi.show()" oncomplete="blkUi.hide()" id="cmdLink"
ajax="false" />
<p:blockUI block="subFrm" trigger="cmdLink" widgetVar="blkUi">
processing...<br />
<p:graphicImage value="/images/ajaxLoader.gif" />
</p:blockUI>
</h:form>
snippet of Managed bean which is of request scope
#ManagedBean
#RequestScoped
public class PdfBean {
// Constants ----------------------------------------------------------------------------------
private static final int DEFAULT_BUFFER_SIZE = 10240; // 10KB.
// Actions ------------------------------------------------------------------------------------
public void downloadPDF() throws IOException {
// Prepare.
FacesContext facesContext = FacesContext.getCurrentInstance();
ExternalContext externalContext = facesContext.getExternalContext();
HttpServletResponse response = (HttpServletResponse) externalContext.getResponse();
String filePath=externalContext.getRealPath("/pdf");
File file = new File(filePath, "modified.pdf");
BufferedInputStream input = null;
BufferedOutputStream output = null;
try {
// Open file.
input = new BufferedInputStream(new FileInputStream(file), DEFAULT_BUFFER_SIZE);
// Init servlet response.
response.reset();
response.setHeader("Content-Type", "application/pdf");
response.setHeader("Content-Length", String.valueOf(file.length()));
response.setHeader("Content-Disposition", "inline; filename=\"" + "modified.pdf" + "\"");
output = new BufferedOutputStream(response.getOutputStream(), DEFAULT_BUFFER_SIZE);
// Write file contents to response.
byte[] buffer = new byte[DEFAULT_BUFFER_SIZE];
int length;
while ((length = input.read(buffer)) > 0) {
output.write(buffer, 0, length);
}
// Finalize task.
output.flush();
} finally {
// Gently close streams.
close(output);
close(input);
}
// Inform JSF that it doesn't need to handle response.
// This is very important, otherwise you will get the following exception in the logs:
// java.lang.IllegalStateException: Cannot forward after response has been committed.
//externalContext.redirect(((HttpServletRequest)externalContext.getRequest()).getRequestURI());
facesContext.responseComplete();
/*FacesContext.getCurrentInstance().getExternalContext()
.redirect("index.xhtml");*/
}
// Helpers (can be refactored to public utility class) ----------------------------------------
private static void close(Closeable resource) {
if (resource != null) {
try {
resource.close();
} catch (IOException e) {
// Do your thing with the exception. Print it, log it or mail it. It may be useful to
// know that this will generally only be thrown when the client aborted the download.
e.printStackTrace();
}
}
}
}

Answer 1

You don't need to open the blockui explicitly. Just remove the code from your commandLink
onclick="blkUi.show()" oncomplete="blkUi.hide()"
remove above. The BlockUI will show up and hides itself.