message in uploaf_folder

src/js/control-view.js

@@ -538,12 +538,12 @@ module.exports = {
     upload_folder: async function (e) {
       this.uploadFolder = true;
       this.filesUploaded = 0;
-      this.totalFiles = files.length;
 
       const files = e.target.files || e.dataTransfer.files;
       if (!files.length) {
         return;
       }
+      this.totalFiles = files.length;
       const folderName = files[0].webkitRelativePath.split("/")[0];
 
       this.config.non_macros_list = [...this.state.non_macros_list];

src/pug/templates/control-view.pug

@@ -275,12 +275,11 @@ script#control-view-template(type="text/x-template")
             .fa.fa-stop-circle-o
 
           message(:show.sync="uploadFolder")
-            h3(slot="header") Uploading
+            h3(slot="header") Files uploading
             div(slot="body") 
-              h3 Uploading files is currently in progress
-              p 
-               |  {{filesUploaded}} files uploaded. 
-               | Do not close window.
+              h3 Please wait...
+              p The files are currently being uploaded.
+              p Do not close the window.
             div(slot="footer")
 
           button.pure-button(title="Execute one program step.", @click="step",