JavaFX 8 创建未修饰的 TextInputDialog，它在全屏舞台上表现为模态

Question

I have a full screen main application stage and want to make a TextInputDialog appear on top, with a modal style (ie the dialog must be dismissed before giving other input to the stage).

If I set the owner to the stage, and the style to UTILITY, then it works.

But if I want to remove decoration (by setting the style to UNDECORATED) then the dialog doesn't appear at all! I can only get it to appear by not setting the parent.

If I don't set the parent, the dialog appears on top of the stage but if I click anywhere else on the application it disappears behind the full screen stage.

How do I create an undecorated dialog that has modal-like behaviour over a full-screen stage?

// This works, but is decorated
TextInputDialog dialog = new TextInputDialog();
dialog.initOwner(stage);
dialog.initStyle(StageStyle.UTILITY);
dialog.showAndWait();

// This doesn't show at all (probably appears underneath the stage?)
TextInputDialog dialog = new TextInputDialog();
dialog.initOwner(stage);
dialog.initStyle(StageStyle.UNDECORATED);
dialog.showAndWait();

// This still allows clicking in the stage while dialog shown. Also causes
// "exit" of fullscreen by showing task bar when dialog is shown
TextInputDialog dialog = new TextInputDialog();
dialog.initStyle(StageStyle.UNDECORATED);
dialog.showAndWait();

Answer 1

I've made a complete example, which appears to be something you've tried, but isn't working. In my case it works great though. The window shows full screen, and the dialog comes up in the center without window decorations.

public class DialogCheck extends Application{

    public static void main(String[] args){
        launch(args);
    }

    @Override
    public void start(Stage primaryStage) throws Exception {
        primaryStage.setTitle("text field");
        BorderPane root = new BorderPane();
        Button b = new Button("dialog");
        root.setCenter(b);
        Scene scene = new Scene(root);
        primaryStage.setScene(scene);
        primaryStage.setFullScreen(true);
        primaryStage.show();

        b.setOnAction((evt)->{ 
            TextInputDialog dialog = new TextInputDialog();
            dialog.initOwner(primaryStage);
            dialog.initStyle(StageStyle.UNDECORATED);
            dialog.showAndWait();
            });


    }

}

Note that this is with java 11 & openjfx 11 on osx.

For some added debugging:

dialog.setOnShown( sevt ->{
            System.out.println("showing: " + dialog.isShowing() + ", " + dialog.getX());
            TextField field = dialog.getEditor();
            field.requestFocus();
            System.out.println(field.isFocused());
        });

Also note the difference between using 'showAndWait' vs 'show'.

Dialog.showAndWait output:

showing: false, NaN.
false

Dialog.show output:

showing: true, 621.0
true