Potential fix for notifications created before area is shown

src/main/java/com/speedment/component/UserInterfaceComponent.java

@@ -23,6 +23,7 @@
 import com.speedment.ui.config.DocumentProperty;
 import com.speedment.internal.ui.controller.ProjectTreeController;
 import com.speedment.internal.ui.util.OutputUtil;
+import de.jensd.fx.glyphs.fontawesome.FontAwesomeIcon;
 import java.util.Optional;
 import java.util.stream.Stream;
 import javafx.collections.ObservableList;
@@ -33,6 +34,7 @@
 import javafx.scene.control.TreeCell;
 import javafx.scene.control.TreeItem;
 import javafx.scene.image.Image;
+import javafx.scene.paint.Color;
 import javafx.stage.Stage;
 import org.controlsfx.control.PropertySheet;
 
@@ -100,6 +102,8 @@ default Class<UserInterfaceComponent> getComponentClass() {
      */
     ObservableList<Node> getOutputMessages();
 
+
+
     /**
      * Returns a stream of all the css-file that should be used to style the UI.
      * 
@@ -168,6 +172,24 @@ static void apply(UISession session, Scene scene) {
      */
     Brand getBrand();
 
+    /**
+     * Container for the fields required to show a notification in the UI.
+     */
+    interface Notification {
+        FontAwesomeIcon icon();
+        String text();
+        Color color();
+        Runnable onClose();
+    }
+
+    /**
+     * Returns an observable list of the notifications that has yet to be shown 
+     * in the UI.
+     * 
+     * @return  the observable list of notifications
+     */
+    ObservableList<Notification> getNotifications();
+
     /**
      * Installs a new context menu builder that will be used in the 
      * {@link ProjectTreeController} of the GUI. This is useful for plugins

src/main/java/com/speedment/internal/core/platform/component/impl/UserInterfaceComponentImpl.java

@@ -18,7 +18,6 @@
 
 import com.speedment.Speedment;
 import com.speedment.SpeedmentVersion;
-import com.speedment.component.Component;
 import com.speedment.component.UserInterfaceComponent;
 import com.speedment.config.db.trait.HasMainInterface;
 import com.speedment.exception.SpeedmentException;
@@ -58,6 +57,7 @@ public final class UserInterfaceComponentImpl extends InternalOpenSourceComponen
 
     private final ObservableList<PropertySheet.Item> properties;
     private final ObservableList<Node> outputMessages;
+    private final ObservableList<Notification> notifications;
     private final ObservableList<TreeItem<DocumentProperty>> selectedTreeItems;
     private final Map<Class<?>, List<UserInterfaceComponent.ContextMenuBuilder<?>>> contextMenuBuilders;
     private final List<String> stylesheets;
@@ -68,6 +68,7 @@ public UserInterfaceComponentImpl(Speedment speedment) {
         super(speedment);
         properties          = observableArrayList();
         outputMessages      = observableArrayList();
+        notifications       = observableArrayList();
         selectedTreeItems   = observableArrayList();
         contextMenuBuilders = new ConcurrentHashMap<>();
         stylesheets         = new CopyOnWriteArrayList<>(DEFAULT_STYLESHEETS);
@@ -120,6 +121,11 @@ public UISession getUISession() throws SpeedmentException {
             );
         } else return session;
     }
+
+    @Override
+    public ObservableList<Notification> getNotifications() {
+        return notifications;
+    }
 
     @Override
     public <DOC extends DocumentProperty & HasMainInterface> void installContextMenu(Class<? extends DOC> nodeType, ContextMenuBuilder<DOC> menuBuilder) {

src/main/java/com/speedment/internal/ui/UISession.java

@@ -26,6 +26,7 @@
 import com.speedment.exception.SpeedmentException;
 import com.speedment.code.TranslatorManager;
 import com.speedment.component.UserInterfaceComponent.Brand;
+import com.speedment.component.UserInterfaceComponent.Notification;
 import com.speedment.internal.ui.config.ProjectProperty; // Exposes internal -> To if and expose all *Property and Mutators
 import com.speedment.internal.logging.Logger;
 import com.speedment.internal.logging.LoggerManager;
@@ -86,6 +87,7 @@
 import de.jensd.fx.glyphs.fontawesome.FontAwesomeIconView;
 import static java.util.Objects.requireNonNull;
 import java.util.concurrent.ExecutionException;
+import javafx.collections.ObservableList;
 import javafx.scene.control.Button;
 import javafx.scene.paint.Color;
 
@@ -126,6 +128,7 @@ public enum ReuseStage {
     private final String defaultConfigLocation;
     private final ProjectProperty project;
     private final PropertySheetFactory propertySheetFactory;
+    private final ObservableList<Notification> notifications;
 
     private File currentlyOpenFile = null;
 
@@ -135,12 +138,14 @@ public UISession(Speedment speedment, Application application, Stage stage, Stri
 
     public UISession(Speedment speedment, Application application, Stage stage, String defaultConfigLocation, Project project) {
 
-        this.speedment = requireNonNull(speedment);
-        this.application = requireNonNull(application);
-        this.stage = requireNonNull(stage);
+        this.speedment             = requireNonNull(speedment);
+        this.application           = requireNonNull(application);
+        this.stage                 = requireNonNull(stage);
         this.defaultConfigLocation = requireNonNull(defaultConfigLocation);
         this.project               = new ProjectProperty();
         this.propertySheetFactory  = new PropertySheetFactory();
+        this.notifications =
+            speedment.getUserInterfaceComponent().getNotifications();
 
         speedment.getUserInterfaceComponent().setUISession(this);
 
@@ -597,28 +602,63 @@ private void showProgressDialog(String title, ProgressMeasure progress, Completa
         }
     }
 
+    private final static class NotificationImpl implements Notification {
+
+        private final String message;
+        private final FontAwesomeIcon icon;
+        private final Color color;
+        private final Runnable onClose;
+
+        public NotificationImpl(String message, FontAwesomeIcon icon, Color color, Runnable onClose) {
+            this.message = requireNonNull(message);
+            this.icon    = requireNonNull(icon);
+            this.color   = requireNonNull(color);
+            this.onClose = requireNonNull(onClose);
+        }
+
+        @Override
+        public String text() {
+            return message;
+        }
+
+        @Override
+        public FontAwesomeIcon icon() {
+            return icon;
+        }
+
+        @Override
+        public Color color() {
+            return color;
+        }
+
+        @Override
+        public Runnable onClose() {
+            return onClose;
+        }
+    }
+
     public void showNotification(String message) {
-        NotificationController.showNotification(this, message);
+        showNotification(message, FontAwesomeIcon.EXCLAMATION);
     }
 
     public void showNotification(String message, FontAwesomeIcon icon) {
-        NotificationController.showNotification(this, message, icon);
+        showNotification(message, icon, NotificationController.BLUE);
     }
 
     public void showNotification(String message, Runnable action) {
-        NotificationController.showNotification(this, message, action);
+        showNotification(message, FontAwesomeIcon.EXCLAMATION, NotificationController.BLUE, action);
     }
 
     public void showNotification(String message, Color color) {
-        NotificationController.showNotification(this, message, color);
+        showNotification(message, FontAwesomeIcon.EXCLAMATION, color);
     }
 
     public void showNotification(String message, FontAwesomeIcon icon, Color color) {
-        NotificationController.showNotification(this, message, icon, color, () -> {});
+        showNotification(message, icon, color, () -> {});
     }
 
     public void showNotification(String message, FontAwesomeIcon icon, Color color, Runnable action) {
-        NotificationController.showNotification(this, message, icon, color, action);
+        notifications.add(new NotificationImpl(message, icon, color, action));
     }
 
     public <DOC extends DocumentProperty> boolean loadFromDatabase(DbmsProperty dbms, String schemaName) {

src/main/java/com/speedment/internal/ui/controller/AboutController.java

@@ -42,12 +42,6 @@
 import javafx.scene.image.ImageView;
 import static java.util.Objects.requireNonNull;
 import static java.util.stream.Collectors.joining;
-import static java.util.Objects.requireNonNull;
-import static java.util.stream.Collectors.joining;
-import static java.util.Objects.requireNonNull;
-import static java.util.stream.Collectors.joining;
-import static java.util.Objects.requireNonNull;
-import static java.util.stream.Collectors.joining;
 
 /**
  *
@@ -104,8 +98,8 @@ public void initialize(URL location, ResourceBundle resources) {
     public static void createAndShow(UISession session) {
         final Stage dialog = new Stage();
 
-        final Parent root = Loader.create(session, "About", AboutController::new, control -> {
-            control.dialog = dialog;
+        final Parent root = Loader.create(session, "About", control -> {
+            ((AboutController) control).dialog = dialog;
         });
 
         final Brand brand = session.getSpeedment().getUserInterfaceComponent().getBrand();

src/main/java/com/speedment/internal/ui/controller/ComponentsController.java

@@ -54,9 +54,6 @@
 import javafx.scene.control.TreeView;
 import javafx.scene.image.Image;
 import static java.util.Objects.requireNonNull;
-import static java.util.Objects.requireNonNull;
-import static java.util.Objects.requireNonNull;
-import static java.util.Objects.requireNonNull;
 
 /**
  *
@@ -300,8 +297,8 @@ private SoftwareItem createSoftwareItem(Software software) {
     public static void createAndShow(UISession session) {
         final Stage dialog = new Stage();
 
-        final Parent root = Loader.create(session, "Components", ComponentsController::new, control -> {
-            control.dialog = dialog;
+        final Parent root = Loader.create(session, "Components", control -> {
+            ((ComponentsController) control).dialog = dialog;
         });
 
         final UserInterfaceComponent.Brand brand = session.getSpeedment().getUserInterfaceComponent().getBrand();

src/main/java/com/speedment/internal/ui/controller/NotificationAreaController.java

@@ -16,9 +16,14 @@
  */
 package com.speedment.internal.ui.controller;
 
+import com.speedment.component.UserInterfaceComponent.Notification;
+import com.speedment.internal.ui.UISession;
 import com.speedment.internal.ui.util.LayoutAnimator;
 import java.net.URL;
+import static java.util.Objects.requireNonNull;
 import java.util.ResourceBundle;
+import javafx.collections.ListChangeListener;
+import javafx.collections.ObservableList;
 import javafx.fxml.FXML;
 import javafx.fxml.Initializable;
 import javafx.scene.layout.FlowPane;
@@ -31,11 +36,13 @@
  */
 public class NotificationAreaController implements Initializable {
 
+    private final UISession session;
     private final LayoutAnimator animator;
     private @FXML FlowPane notificationArea;
 
-    public NotificationAreaController() {
-        animator = new LayoutAnimator();
+    public NotificationAreaController(UISession session) {
+        this.session  = requireNonNull(session);
+        this.animator = new LayoutAnimator();
     }
 
     /**
@@ -44,5 +51,31 @@ public NotificationAreaController() {
     @Override
     public void initialize(URL url, ResourceBundle rb) {
         animator.observe(notificationArea.getChildren());
+
+        final ObservableList<Notification> notifications = session.getSpeedment()
+                .getUserInterfaceComponent()
+                .getNotifications();
+
+        notifications.addListener((ListChangeListener.Change<? extends Notification> change) -> {
+            while (change.next()) {
+                if (change.wasAdded()) {
+                    change.getAddedSubList().forEach(n -> {
+                        NotificationController.showNotification(
+                            session, n.text(), n.icon(), n.color(), n.onClose()
+                        );
+
+                        notifications.remove(n);
+                    });
+                }
+            }
+        });
+
+        while (!notifications.isEmpty()) {
+            final Notification n = notifications.get(0);
+            NotificationController.showNotification(
+                session, n.text(), n.icon(), n.color(), n.onClose()
+            );
+            notifications.remove(0);
+        }
     }
 }

src/main/java/com/speedment/internal/ui/controller/NotificationController.java

@@ -103,31 +103,17 @@ public void initialize(URL url, ResourceBundle rb) {
             seq.play();
         }
     }
-
-    public static void showNotification(UISession session, String message) {
-        showNotification(session, message, DEFAULT_ICON);
-    }
-
-    public static void showNotification(UISession session, String message, Color color) {
-        showNotification(session, message, DEFAULT_ICON, color, () -> {});
-    }
-
-    public static void showNotification(UISession session, String message, FontAwesomeIcon icon) {
-        showNotification(session, message, icon, DEFAULT_COLOR, () -> {});
-    }
-
-    public static void showNotification(UISession session, String message, Runnable onClose) {
-        showNotification(session, message, DEFAULT_ICON, DEFAULT_COLOR, onClose);
-    }
-
-    public static void showNotification(UISession session, String message, FontAwesomeIcon icon, Color color, Runnable onClose) {
+
+    static void showNotification(UISession session, String message, FontAwesomeIcon icon, Color color, Runnable onClose) {
         final FlowPane area = (FlowPane) session.getStage().getScene().lookup(NOTIFICATION_AREA_ID);
 
         if (area == null) {
-            throw new SpeedmentException(
+            session.showError(
+                "Error Creating Notification",
                 "Could not find the '" + NOTIFICATION_AREA_ID + 
                 "' node in the JavaFX scene."
             );
+            return;
         }
 
         final FXMLLoader loader = new FXMLLoader(NotificationController.class.getResource(NOTIFICATION_FXML));