I am relatively new to JSF thus need some help.
Problem: I have webpage that displays a PDF. Thus I created a xhtml as follow
<p:panel rendered="#{mainAppView.getMessages().isEmpty()}" styleClass="preview-panel">
<div class="document-viewer-wrapper">
<pe:documentViewer
url="#{previewView.previewUrl}"
download="Document.pdf"
id="pdfPreview"/>
</div>
</p:panel>
URL is provided by a BackingBean previewView. Thus when the jsf tries to display the document, it makes a call to WebServlet. The WebServlet downloads the document and displays it and if it fails to download, an error message is shown on the DocumentViewer.
Is there a way to I can notify the ViewScope Bean about the failure? I want to disable a tab on the screen if the document download fails. I read that servlet can't make call to viewScope Bean.
I ended up writing a JS to achieve the desire result. JS monitored the pdfviewer and if it fails to load the document, I updated the message on the pdfviewer.