AbbruchButton als Link mittig unterhalb der LoginBox eingefügt.

(Zur Sicherstellung der Anforderung, dass alle Vorgänge abbrechbar sein sollen)

src/main/java/org/s4s/gui/views/LoginView.java

@@ -4,6 +4,7 @@ import com.vaadin.navigator.ViewChangeListener;
 import com.vaadin.server.FontAwesome;
 import com.vaadin.shared.ui.label.ContentMode;
 import com.vaadin.ui.*;
+import com.vaadin.ui.themes.ValoTheme;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 import org.s4s.dao.KundenDAO;
@@ -53,19 +54,34 @@ public class LoginView extends TemplateView {
 
         Button button = new Button("Login", FontAwesome.BEER);
         Button buttonReg = new Button("Registrieren", FontAwesome.BEER);
+        Button abbruch = new Button("Abbruch");
+        abbruch.setIcon(FontAwesome.STOP_CIRCLE);
+        abbruch.addStyleName(ValoTheme.BUTTON_LINK);
         hLay.addComponent(button);
         Label lbl = new Label("&nbsp", ContentMode.HTML);
         hLay.addComponent(lbl);
         hLay.addComponent(buttonReg);
         layout.addComponent(label);
         layout.addComponent(hLay);
-
+        
+        VerticalLayout box = new VerticalLayout();
         HorizontalLayout horSpacer = new HorizontalLayout();
         horSpacer.addComponent(layout);
-        this.addComponent(horSpacer);
+        box.addComponent(horSpacer);
         horSpacer.setComponentAlignment(layout, Alignment.MIDDLE_CENTER);
 
-        this.setComponentAlignment(horSpacer, Alignment.MIDDLE_CENTER);
+        box.setComponentAlignment(horSpacer, Alignment.MIDDLE_CENTER);
+        
+        HorizontalLayout abbruchSpacer = new HorizontalLayout();
+        abbruchSpacer.addComponent(abbruch);
+        Label lb = new Label("&nbsp", ContentMode.HTML);
+        box.addComponent(lb);
+        box.addComponent(abbruchSpacer);
+        
+        box.setComponentAlignment(abbruchSpacer, Alignment.MIDDLE_CENTER);
+        
+        this.addComponent(box);
+        this.setComponentAlignment(box, Alignment.MIDDLE_CENTER);
         button.addClickListener((Button.ClickEvent event) -> {
             String login = userLogin.getValue();
             String password = passwordField.getValue();
@@ -91,6 +107,9 @@ public class LoginView extends TemplateView {
         buttonReg.addClickListener((Button.ClickEvent event) -> {
             UI.getCurrent().getNavigator().navigateTo(Views.REGISTRIERUNG);
         });
+         abbruch.addClickListener(e -> {
+            UI.getCurrent().getNavigator().navigateTo(Views.WELCOME);
+        });
     }
 
 }