print-pdf using callback iso timer

Use window.callPhantom icw page. onCallback to wait for pdf-ready event.
From: http://stackoverflow.com/a/28925479/129269

plugin/print-pdf/print-pdf.js

@@ -6,6 +6,7 @@
  *
  * @author Manuel Bieh (https://github.com/manuelbieh)
  * @author Hakim El Hattab (https://github.com/hakimel)
+ * @author Manuel Riezebosch (https://github.com/riezebosch)
  */
 
 // html2pdf.js
@@ -21,11 +22,11 @@ if( outputFile.match( /\.pdf$/gi ) === null ) {
 	outputFile += '.pdf';
 }
 
-console.log( 'Export PDF: Reading reveal.js config [1/3]' );
+console.log( 'Export PDF: Reading reveal.js config [1/4]' );
 
 probePage.open( inputFile, function( status ) {
 
-	console.log( 'Export PDF: Preparing print layout [2/3]' );
+	console.log( 'Export PDF: Preparing print layout [2/4]' );
 
 	var config = probePage.evaluate( function() {
 		return Reveal.getConfig();
@@ -40,14 +41,22 @@ probePage.open( inputFile, function( status ) {
 		};
 
 		printPage.open( inputFile, function( status ) {
-			window.setTimeout( function() {
-				console.log( 'Export PDF: Writing file [3/3]' );
+			console.log( 'Export PDF: Preparing pdf [3/4]')
+			printPage.evaluate(function() {
+				Reveal.isReady() ? window.callPhantom() : Reveal.addEventListener( 'pdf-ready', window.callPhantom );
+			});
+		} );
+
+		printPage.onCallback = function(data) {
+			// For some reason we need to "jump the queue" for syntax highlighting to work.
+			// See: http://stackoverflow.com/a/3580132/129269
+			setTimeout(function() {
+				console.log( 'Export PDF: Writing file [4/4]' );
 				printPage.render( outputFile );
 				console.log( 'Export PDF: Finished successfully!' );
 				phantom.exit();
-			}, 1000 );
-		} );
-
+			}, 0);
+		};
 	}
 	else {
 
@@ -55,7 +64,6 @@ probePage.open( inputFile, function( status ) {
         phantom.exit(1);
 
     }
-
 } );