when data is loaded from server info icon appears in the client app

frontend-js/src/main/js/gui/leftPanel/Footer.js

@@ -59,26 +59,57 @@ Footer.prototype._createFooterGui = function() {
   link.href = ServerConnector.getServerBaseUrl() + "/export.xhtml?id=" + projectId;
   self.getElement().appendChild(link);
 
+  var loadingDiv = Functions.createElement({
+    type : "div",
+    style : "display:none; ",
+  });
+  loadingDiv.style.height = "100%";
+  loadingDiv.style.float = "right";
+  self.getElement().appendChild(loadingDiv);
+
   var loadingImg = Functions.createElement({
     type : "img",
-    style : "display:none; ",
     src : 'resources/images/icons/ajax-loader.gif',
   });
   loadingImg.style.height = "100%";
-  loadingImg.style.float = "right";
-  self.getElement().appendChild(loadingImg);
-  this.setControlElement(PanelControlElementType.FOOTER_LOADING_DIV, loadingImg);
+  loadingDiv.appendChild(loadingImg);
+  this.setControlElement(PanelControlElementType.FOOTER_LOADING_DIV, loadingDiv);
 
 };
 
+Footer.prototype.addLoadMessage = function(message) {
+  var self = this;
+  self._loadMessages.push(message);
+};
+Footer.prototype.removeLoadMessage = function(message) {
+  var self = this;
+  var index = self._loadMessages.indexOf(message);
+  if (index > -1) {
+    self._loadMessages.splice(index, 1);
+  } else {
+    logger.warn("Removing message that is not there: " + message);
+  }
+};
+
 Footer.prototype.init = function() {
   var self = this;
   return new Promise(function(resolve) {
+    var div = self.getControlElement(PanelControlElementType.FOOTER_LOADING_DIV);
+
+    self._loadMessages = [];
     self._onDataLoadStart = function(e) {
-      logger.debug("Loading started: " + e.arg);
+      self.addLoadMessage(e.arg);
+      div.style.display = "block";
+      div.title = e.arg;
     }
+
     self._onDataLoadStop = function(e) {
-      logger.debug("Loading finished: " + e.arg);
+      self.removeLoadMessage(e.arg);
+      if (self._loadMessages.length > 0) {
+        div.title = self._loadMessages[0];
+      } else {
+        div.style.display = "none";
+      }
     }
     ServerConnector.addListener("onDataLoadStart", self._onDataLoadStart);
     ServerConnector.addListener("onDataLoadStop", self._onDataLoadStop);