[prmr#538] Add dark mode for Properties and Alert dialogs.

src/org/jetuml/gui/DiagramCanvas.java

@@ -209,7 +209,7 @@ public void editSelected()
 		Optional<DiagramElement> edited = getLastSelected();
 		if( edited.isPresent() )
 		{
-			PropertyEditorDialog dialog = new PropertyEditorDialog((Stage)getScene().getWindow(), 
+			PropertyEditorDialog dialog = new PropertyEditorDialog( ((EditorFrame) getScene().getRoot()).getDialogStage(), 
 					edited.get(), ()-> paintPanel());
 
 			CompoundOperation operation = dialog.show();

src/org/jetuml/gui/DiagramTab.java

@@ -45,6 +45,7 @@
 import javafx.scene.image.Image;
 import javafx.scene.layout.BorderPane;
 import javafx.scene.layout.StackPane;
+import javafx.stage.Stage;
 
 /**
  * A tab holding a single diagram.

src/org/jetuml/gui/DialogStage.java

@@ -9,20 +9,24 @@
 
 /**
  * A Stage that is to be shared by different dialogs.
- * Different dialogs sharing a common stage simplifies 
- * applying the dark mode theme to the dialogs.
+ * Different dialogs sharing a common stage simplifies applying 
+ * the dark mode theme to the dialogs. There is only one DialogStage
+ * in the program's life cycle.
  */
 public class DialogStage extends Stage
 {		
 	/**
 	 * Creates the stage for different dialogs.
+	 * Dialogs that use this stage should not change the scene - doing
+	 * so will stop applying the dark theme to dialogs. Instead,
+	 * dialogs can customize the UI by reassigning the root of the scene.
 	 * 
 	 * @param pOwner The main JetUML stage.
 	 */
 	public DialogStage(Stage pOwner)
 	{
-		Scene dialogScene = new Scene(new GridPane());
-		setScene(dialogScene);
+		// The root is defined only for compilation.
+		setScene(new Scene(new GridPane()));
 		setResizable(false);
 		initModality(Modality.WINDOW_MODAL);
 		initOwner(pOwner);

src/org/jetuml/gui/EditorFrame.java

@@ -320,6 +320,7 @@ private void open(File pFile)
 		{
 			Alert alert = new DeserializationErrorAlert(exception);
 			alert.initOwner(aMainStage);
+			applyDarkTheme(alert);
 			alert.showAndWait();
 		}
 	}
@@ -441,6 +442,7 @@ private void close()
 			alert.initOwner(aMainStage);
 			alert.setTitle(RESOURCES.getString("dialog.close.title"));
 			alert.setHeaderText(RESOURCES.getString("dialog.close.title"));
+			applyDarkTheme(alert);
 			alert.showAndWait();
 
 			if(alert.getResult() == ButtonType.YES) 
@@ -469,6 +471,7 @@ public void close(DiagramTab pDiagramTab)
 			alert.initOwner(aMainStage);
 			alert.setTitle(RESOURCES.getString("dialog.close.title"));
 			alert.setHeaderText(RESOURCES.getString("dialog.close.title"));
+			applyDarkTheme(alert);
 			alert.showAndWait();
 
 			if(alert.getResult() == ButtonType.YES) 
@@ -507,6 +510,7 @@ private void save()
 		{
 			Alert alert = new Alert(AlertType.ERROR, RESOURCES.getString("error.save_file"), ButtonType.OK);
 			alert.initOwner(aMainStage);
+			applyDarkTheme(alert);
 			alert.showAndWait();
 		}
 	}
@@ -552,6 +556,7 @@ private void saveAs()
 		{
 			Alert alert = new Alert(AlertType.ERROR, RESOURCES.getString("error.save_file"), ButtonType.OK);
 			alert.initOwner(aMainStage);
+			applyDarkTheme(alert);
 			alert.showAndWait();
 		}
 	}
@@ -623,6 +628,7 @@ else if("bmp".equals(format))	// to correct the BufferedImage type
 		{
 			Alert alert = new Alert(AlertType.ERROR, RESOURCES.getString("error.save_file"), ButtonType.OK);
 			alert.initOwner(aMainStage);
+			applyDarkTheme(alert);
 			alert.showAndWait();
 		}
 	}
@@ -684,6 +690,7 @@ public void exit()
 			alert.initOwner(aMainStage);
 			alert.setTitle(RESOURCES.getString("dialog.exit.title"));
 			alert.setHeaderText(RESOURCES.getString("dialog.exit.title"));
+			applyDarkTheme(alert);
 			alert.showAndWait();
 
 			if(alert.getResult() == ButtonType.YES) 
@@ -699,6 +706,16 @@ public void exit()
 		}
 	}		
 
+	/**
+	 * Getter for the dialog stage.
+	 * 
+	 * @return The dialog stage.
+	 */
+	public Stage getDialogStage()
+	{
+		return aDialogStage;
+	}
+
 	private List<Tab> tabs()
 	{
 		return ((TabPane) getCenter()).getTabs();
@@ -749,7 +766,13 @@ private void removeGraphFrameFromTabbedPane(DiagramTab pTab)
 		showWelcomeTabIfNecessary();
 	}
 
-
+	private void applyDarkTheme(Alert pAlert)
+	{
+		if( UserPreferences.instance().getBoolean(BooleanPreference.darkMode) )
+		{
+			pAlert.getDialogPane().getStylesheets().add(aDarkModeURL);
+		}
+	}
 
 	@Override
 	public void booleanPreferenceChanged(BooleanPreference pPreference)

src/org/jetuml/gui/PropertyEditorDialog.java

@@ -37,6 +37,7 @@
 import javafx.scene.control.Button;
 import javafx.scene.image.Image;
 import javafx.scene.layout.BorderPane;
+import javafx.scene.layout.Pane;
 import javafx.stage.Modality;
 import javafx.stage.Stage;
 
@@ -48,34 +49,32 @@ public class PropertyEditorDialog
 {
 	private static final int LAYOUT_PADDING = 20;
 
-	private final Stage aStage = new Stage();
+	private final Stage aStage;
 	private final DiagramElement aElement;
 
 	/**
 	 * Creates a new dialog.
 	 * 
-	 * @param pOwner The stage that owns this stage.
+	 * @param pDialogStage The stage that owns this stage.
 	 * @param pElement The element to edit with this dialog.
 	 * @param pPropertyChangeListener A callback to run whenever a property changes.
 	 */
-	public PropertyEditorDialog( Stage pOwner, DiagramElement pElement, 
+	public PropertyEditorDialog( Stage pDialogStage, DiagramElement pElement, 
 			PropertySheet.PropertyChangeListener pPropertyChangeListener )
 	{
+		aStage = pDialogStage;
 		aElement = pElement;
-		prepareStage(pOwner);
-		aStage.setScene(createScene(pPropertyChangeListener));
+		prepareStage();
+		aStage.getScene().setRoot(createRoot(pPropertyChangeListener));
 	}
 
-	private void prepareStage(Stage pOwner) 
+	private void prepareStage() 
 	{
-		aStage.setResizable(false);
-		aStage.initModality(Modality.APPLICATION_MODAL);
-		aStage.initOwner(pOwner);
 		aStage.setTitle(RESOURCES.getString("dialog.properties"));
 		aStage.getIcons().add(new Image(RESOURCES.getString("application.icon")));
 	}
 
-	private Scene createScene(PropertySheet.PropertyChangeListener pPropertyChangeListener) 
+	private Pane createRoot(PropertySheet.PropertyChangeListener pPropertyChangeListener) 
 	{
 		PropertySheet sheet = new PropertySheet(aElement, pPropertyChangeListener);
 
@@ -92,7 +91,7 @@ private Scene createScene(PropertySheet.PropertyChangeListener pPropertyChangeLi
 		layout.setCenter(sheet);
 		layout.setBottom(button);
 
-		return new Scene(layout);
+		return layout;
 	}
 
 	private PropertySheet getPropertySheet()

src/org/jetuml/gui/tips/TipDialog.java

@@ -170,7 +170,7 @@ private static HBox createEmptyTipMenu()
 	{
 		HBox tipMenu = new HBox();
 		tipMenu.setPadding(new Insets(PADDING));
-		tipMenu.setStyle("-fx-background-color: gainsboro;");
+		tipMenu.setStyle("-fx-background-color: slategrey;");
 
 		BorderStroke bs = new BorderStroke(Color.DARKGRAY, BorderStrokeStyle.SOLID,
 										   CornerRadii.EMPTY, BorderWidths.DEFAULT);