An example of how to use the confirmation pop up in JSF

 
function checkInput(objectSource) { 
if(objectSource.onclick){ 
objectSource.oldOnClick = objectSource.onclick; 
objectSource.onclick = null; 
} 

var attachfile = $('#attachment').val(); 
if(content.indexOf(" The attachment ") != -1 && attachfile == undefined) { 
if(!confirm( ' Your email mentions attachments, but you may have forgotten to add them. ')){ 
return false; 
} 
} 
objectSource.oldOnClick(); 
}