fix viewer

src/assets/www/pdfjs/web/viewer.html

@@ -298,6 +298,9 @@
         </menu>
 
         <div id="viewerContainer" tabindex="0">
+          <div id="loader" style="color: white;font-size: 16px;margin-bottom: -100%;top: 50px;position: relative;/* display: none; */margin-bottom: -18px;/* left: 50px; *//* text-align: center; */height: calc(100% - 0px);justify-content: center;align-items: center;display: flex;position: absolute;top: 0px;left: 0px;width: 100%;z-index: 1111111;text-align: center;">
+            Estamos a preparar a visualização do documento.<br> Por favor aguarde.
+          </div>
           <div id="viewer" class="pdfViewer"></div>
         </div>
 
@@ -407,5 +410,23 @@
     </div> <!-- outerContainer -->
     <div id="printContainer"></div>
   </body>
+  <script>
+    function loader() {
+
+      let viewerContext = document.getElementById("viewer").innerHTML
+      viewerContext = viewerContext.replace(" ", "")
+      if(!viewerContext) {
+        setTimeout(() => {
+          loader()
+        }, 500)
+      } else {
+        document.getElementById("loader").remove()
+      }
+    }
+
+    setTimeout(() => {
+      loader()
+    }, 1000)
+  </script>
 </html>