new home screen, tutorial fxml file and missing javadoc

src/main/java/ch/zhaw/gartenverwaltung/MainFXMLController.java

@@ -4,7 +4,6 @@ import ch.zhaw.gartenverwaltung.bootstrap.AfterInject;
 import ch.zhaw.gartenverwaltung.bootstrap.AppLoader;
 import ch.zhaw.gartenverwaltung.bootstrap.ChangeViewEvent;
 import ch.zhaw.gartenverwaltung.bootstrap.Inject;
-import javafx.event.ActionEvent;
 import javafx.event.EventHandler;
 import javafx.fxml.FXML;
 import javafx.scene.control.*;
@@ -41,26 +40,39 @@ public class MainFXMLController {
     @FXML
     private Button tutorial_button;
 
+    /**
+     * go to home pane
+     */
     @FXML
     void goToHome() {
         showPaneAsMainView("Home.fxml");
         styleChangeButton(home_button);
     }
 
+    /**
+     * go to my garden pane
+     */
     @FXML
     void goToMyPlants() {
         showPaneAsMainView("MyGarden.fxml");
         styleChangeButton(myGarden_button);
     }
 
+    /**
+     * go to the schedule pane
+     */
     @FXML
     void goToMySchedule() {
         showPaneAsMainView("MySchedule.fxml");
         styleChangeButton(mySchedule_button);
     }
 
+    /**
+     * open dialog of the settings
+     * @throws IOException exception
+     */
     @FXML
-    public void openSettings(ActionEvent actionEvent) throws IOException {
+    public void openSettings() throws IOException {
         Dialog<ButtonType> dialog = new Dialog<>();
         dialog.setTitle("Settings");
         dialog.setHeaderText("Settings");
@@ -82,8 +94,11 @@ public class MainFXMLController {
         }
     }
 
-    public void goToTutorial(ActionEvent actionEvent) {
-        //showPaneAsMainView("Tutorial.fxml");
+    /**
+     * go to Tutorial pane
+     */
+    public void goToTutorial() {
+        showPaneAsMainView("Tutorial.fxml");
         styleChangeButton(tutorial_button);
     }
 
@@ -109,10 +124,15 @@ public class MainFXMLController {
 
     private final EventHandler<ChangeViewEvent> changeMainViewHandler = (ChangeViewEvent event) -> showPaneAsMainView(event.view());
 
+    /**
+     * preload all menu bar panes
+     * @throws IOException exception
+     */
     private void preloadPanes() throws IOException {
         appLoader.loadAndCacheFxml("MyGarden.fxml");
         appLoader.loadAndCacheFxml("MySchedule.fxml");
         appLoader.loadAndCacheFxml("Plants.fxml");
+        appLoader.loadAndCacheFxml("Tutorial.fxml");
     }
 
     private void styleChangeButton(Button button) {
@@ -142,7 +162,7 @@ public class MainFXMLController {
     }
 
     /**
-     * adds icon to button
+     * adds icon to given button
      * @param button the button which get the icon
      * @param iconFileName file name of icon
      */