Fix: Disable zipManagerBtn during loading

CityDoctorParent/Extensions/CityDoctorGUI/src/main/java/de/hft/stuttgart/citydoctor2/gui/CityDoctorController.java

@@ -79,6 +79,7 @@ public class CityDoctorController {
         try {
             Platform.runLater(() -> {
                 mainWindow.getOpenBtn().setDisable(true);
+                mainWindow.getZipManagerBtn().setDisable(true);
                 mainWindow.getWriteReportButton().setDisable(true);
                 mainWindow.getMeshGroup().getChildren().clear();
 
@@ -90,6 +91,7 @@ public class CityDoctorController {
                 loadCityGmlZipFile(path, numberOfRoundingPlaces, l, useValidation, lowMemory);
                 return;
             }
+            currentZipEntryManager = null;
             currentChecker = null;
             currentConfig = new ParserConfiguration(numberOfRoundingPlaces, useValidation, lowMemory);
             GMLValidationHandler handler = null;
@@ -181,6 +183,7 @@ public class CityDoctorController {
         try {
             Platform.runLater(() -> {
                 mainWindow.getOpenBtn().setDisable(true);
+                mainWindow.getZipManagerBtn().setDisable(true);
                 mainWindow.getWriteReportButton().setDisable(true);
                 mainWindow.getMeshGroup().getChildren().clear();
                 clearTrees();