Stage is hidden when dialog is shown - javafx-2

Question

I have this code which displays confirmation dialog to exit application.
public class DialogPanels
{
public void initClosemainAppDialog(final Stage primaryStage)
{
primaryStage.setOnCloseRequest(new EventHandler<WindowEvent>()
{
#Override
public void handle(WindowEvent event)
{
event.consume(); // Do nothing on close request
// Dialog Stage init
final Stage dialog = new Stage();
dialog.initModality(Modality.APPLICATION_MODAL);
// Frage - Label
Label label = new Label("Exit from the program");
// Button "Yes"
Button okBtn = new Button("Yes");
okBtn.setOnAction(new EventHandler<ActionEvent>()
{
#Override
public void handle(ActionEvent event)
{
//primaryStage.close();
//dialog.close();
//Platform.exit();
System.exit(0);
}
});
// Button "No"
Button cancelBtn = new Button("No");
cancelBtn.setOnAction(new EventHandler<ActionEvent>()
{
#Override
public void handle(ActionEvent event)
{
primaryStage.show();
dialog.close();
}
});
// Layout for the Button
HBox hbox = new HBox();
hbox.setSpacing(10);
hbox.setAlignment(Pos.CENTER);
hbox.getChildren().add(okBtn);
hbox.getChildren().add(cancelBtn);
// Layout for the Label and hBox
VBox vbox = new VBox();
vbox.setAlignment(Pos.CENTER);
vbox.setSpacing(10);
vbox.getChildren().add(label);
vbox.getChildren().add(hbox);
// Stage
Scene scene = new Scene(vbox);
dialog.setScene(scene);
dialog.show();
}
});
}
}
The problem is that when close the main application the dialog box is displayed and the main stage is hidden. I want to display the dialog box in front of the main stage. Can you help me to correct this?
UPDATE
I tested this code, it's working but when the dialog is displayed the mainstage is not responsible(frozen). How I an make the mainstage responsible when I display dialog?

Answer 1

Consume the closing event and set the owner of the stage if you do not want to see another window when the windows are minimized:
#Override
public void handle(WindowEvent event)
{
event.consume(); // Do nothing on close request
// Dialog Stage init
final Stage dialog = new Stage();
dialog.initModality(Modality.APPLICATION_MODAL);
dialog.initOwner(primaryStage);
// other stuff
}
});

Answer 2

You need to set the proper relationships between primaryStage and dialog stage. Here's a hint to get you going:
...
dialog.initOwner(primaryStage);
dialog.initModality(Modality.APPLICATION_MODAL);
dialog.showAndWait();
You can find more information in Oracle's JavaFX 2 JavaDocs.
More example code (edit)
I'm using setOnHiding(..) instead of setOnCloseRequest(..):
stage.setOnHiding(new AskUserIfHeReallyWantsToQuitWindowHandler(stage));
I extracted your code into a seperate event handler class and fixed the issues I mentioned (sorry, I am little short on time right now):
public class AskUserIfHeReallyWantsToQuitWindowHandler implements EventHandler<WindowEvent> {
private final Stage primaryStage;
public AskUserIfHeReallyWantsToQuitWindowHandler(final Stage primaryStage) {
Objects.requireNonNull(primaryStage);
this.primaryStage = primaryStage;
}
#Override
public void handle(final WindowEvent event) {
event.consume();
final Stage dialog = new Stage();
final Button okBtn = new Button("Yes");
okBtn.setOnAction(new EventHandler<ActionEvent>() {
#Override
public void handle(final ActionEvent event) {
dialog.close();
primaryStage.close();
}
});
// Button "No"
final Button cancelBtn = new Button("No");
cancelBtn.setOnAction(new EventHandler<ActionEvent>() {
#Override
public void handle(final ActionEvent event) {
dialog.close();
Platform.runLater(new Runnable() {
#Override
public void run() {
primaryStage.show();
}
});
}
});
// Layout for the Button
final HBox hbox = new HBox();
hbox.setSpacing(10);
hbox.setAlignment(Pos.CENTER);
hbox.getChildren().add(okBtn);
hbox.getChildren().add(cancelBtn);
// Layout for the Label and hBox
final VBox vbox = new VBox();
vbox.setAlignment(Pos.CENTER);
vbox.setSpacing(10);
vbox.getChildren().add(new Label("Do your really want to exit?"));
vbox.getChildren().add(hbox);
// Stage
final Scene scene = new Scene(vbox);
dialog.setScene(scene);
dialog.initOwner(primaryStage);
dialog.initModality(Modality.NONE);
dialog.showAndWait();
}
}