Add about feature

src/main/java/app/Main.java

@@ -58,6 +58,7 @@ public class Main extends Application {
     MainController mainController = fxmlLoader.getController();
     mainController.getEventBus().post(new LanguageChangedEvent("Java"));
     mainController.getEventBus().post(new FileSaveStateChangedEvent(true));
+    mainController.setHostServices(getHostServices());
   }
 
   /**
@@ -75,6 +76,8 @@ public class Main extends Application {
 
     window.setScene(scene);
     window.show();
+
+    getHostServices().showDocument("https://google.com");
   }
 
 }

src/main/java/app/MainController.java

@@ -10,7 +10,9 @@ import com.google.common.eventbus.Subscribe;
 import app.controllers.*;
 import app.events.ExitApplicationEvent;
 import app.events.LanguageChangedEvent;
+import app.events.OpenLinkInBrowserEvent;
 import app.model.Model;
+import javafx.application.HostServices;
 import javafx.application.Platform;
 import javafx.fxml.FXML;
 import javafx.fxml.Initializable;
@@ -30,6 +32,7 @@ public class MainController implements Initializable {
   private MenubarController menubarController;
 
   private EventBus eventBus;
+  private HostServices hostServices;
 
   @Override
   public void initialize(URL url, ResourceBundle resourceBundle) {
@@ -53,6 +56,15 @@ public class MainController implements Initializable {
     return this.eventBus;
   }
 
+
+  public HostServices getHostServices() {
+    return hostServices;
+  }
+
+  public void setHostServices(HostServices hostServices) {
+    this.hostServices = hostServices;
+  }
+
   /**
    * Change the CSS according to which language is being used.
    * @param event
@@ -73,6 +85,12 @@ public class MainController implements Initializable {
     Model.getScene().getStylesheets().add(nextStyleSheet);
   }
 
+
+  @Subscribe
+  private void handle(OpenLinkInBrowserEvent event) {
+    this.getHostServices().showDocument(event.getLink());
+  }
+
   /**
    * Handle an exit request for the whole program.
    * @param event

src/main/java/app/controllers/MenubarController.java

@@ -9,6 +9,7 @@ import com.google.common.eventbus.Subscribe;
 
 import app.events.ExitApplicationEvent;
 import app.events.LanguageChangedEvent;
+import app.events.OpenLinkInBrowserEvent;
 import app.events.ToggleCommentEvent;
 import javafx.event.ActionEvent;
 import javafx.fxml.FXML;
@@ -120,6 +121,11 @@ public class MenubarController implements Initializable, Controller {
   /*                                   ABOUT                                  */
   /* ------------------------------------------------------------------------ */
 
+  @FXML
+  private void handleAbout(ActionEvent event) {
+    String aboutLink = "https://gitlab.stud.idi.ntnu.no/oysteikt/tdt4100-project-2021v/-/blob/master/README.md";
+    this.eventBus.post(new OpenLinkInBrowserEvent(aboutLink));
+  }
 
   /* ------------------------------------------------------------------------ */
   /*                               SUBSCRIPTIONS                              */

src/main/java/app/events/OpenLinkInBrowserEvent.java

@@ -0,0 +1,15 @@
+package app.events;
+
+public class OpenLinkInBrowserEvent extends Event {
+
+  private String link;
+
+  public OpenLinkInBrowserEvent(String link) {
+    this.link = link;
+  }
+
+  public String getLink() {
+    return link;
+  }
+  
+}

src/main/resources/fxml/components/Menubar.fxml

@@ -67,7 +67,7 @@
       <items>
         <MenuItem mnemonicParsing="false" text="Tips and tricks" accelerator="f1"/>
         <MenuItem mnemonicParsing="false" text="Keyboard Shortcut list" accelerator="f2"/>
-        <MenuItem mnemonicParsing="false" text="About" accelerator="f3"/>
+        <MenuItem mnemonicParsing="false" text="About" accelerator="f3" onAction="#handleAbout"/>
       </items>
     </Menu>
   </menus>