Add new controller friends

src/Client/src/main/java/greenify/client/controller/FriendController.java

@@ -0,0 +1,56 @@
+package greenify.client.controller;
+
+import greenify.client.Friend;
+import greenify.client.rest.UserService;
+import javafx.collections.FXCollections;
+import javafx.collections.ObservableList;
+import javafx.event.ActionEvent;
+import javafx.fxml.FXML;
+import javafx.scene.control.*;
+import javafx.stage.Stage;
+import javafx.stage.Window;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Controller;
+
+@Controller
+public class FriendController {
+    @Autowired
+    UserService userService;
+
+    public static ObservableList<Friend> data = FXCollections.observableArrayList();
+
+    @FXML
+    private Button addButton;
+    @FXML
+    private TextField userNameText;
+
+    /**
+     * Signs up the user.
+     * @param event the click of the sign up button
+     */
+    @FXML
+    public void addFriend(ActionEvent event) {
+        //set the window to the current window (for displaying the alerts)
+        Window owner = addButton.getScene().getWindow();
+        //check if the username field is empty
+        if (userNameText.getText().isEmpty()) {
+            //if so, display an alert
+            UserController.AlertHelper.showAlert(Alert.AlertType.ERROR, owner, "Username Error!",
+                    "Please enter a username!");
+            return;
+        }
+        //add friend to the current user
+        userService.addFriend(userService.currentUser.getName(), userNameText.getText());
+        Friend friend = new Friend(userNameText.getText(),
+                userService.getFootprint(userNameText.getText()));
+        data.add(friend);
+        //close the register window after the user has entered all the credentials
+        Stage current = (Stage) owner;
+        current.close();
+    }
+
+    public static ObservableList<Friend> getData() {
+        return data;
+    }
+
+}