javafx.stage.Modality

JavaFX 2 でダイアログを出す方法なんですが基本的なコードがforums.oracle.comにありました。
javafx.stage.Popup as JOptionPane
API javafx.stage.Modality
モーダルダイアログの一例です

ModalDialog.java

import javafx.stage.*; 
import javafx.scene.*;
import javafx.scene.paint.Color;
import javafx.scene.control.*;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
 
public class ModalDialog {

    private Label label = new Label("What is your name ?");
    private Button btn;
    /*  Mainクラスのインスタンス代入用 */
    private  ModalTest parent;
    /*  MainクラスのStageとMainクラスのインスタンスを受け取るコンストラクタ
      *  この場合はMainクラスをダイアログのownerとしている
      */
    public ModalDialog(final Stage owner_stg, ModalTest mt) {
        
	 parent = mt;
        btn = new Button();
	final TextField tf = new TextField();
     /* ModalDialog にするStage */    
        final  Stage stage = new Stage();   
	
        /*  modalのタイプでStage（ダイアログ）を初期化
	* 他に Modality.WINDOW_MODAL,  Modality.NONEがある
        */
	stage.initModality(Modality.APPLICATION_MODAL);
	
        //ダイアログのownerをセットする
        stage.initOwner(owner_stg);
        stage.setTitle("Dialog Stage");
        Group root = new Group();
         Scene scene = new Scene(root, 380, 250, Color.web("#0000FF", 0.3));
        
         
         btn.setOnAction(new EventHandler<ActionEvent>() {
 
            public void handle(ActionEvent event) {
	        String name = tf.getText();
	        parent.setText_TextArea("Hi ! " + name);
		tf.deleteText(0, name.length());
             //stage.hide();
	         stage.close();
		
	        ConfirmModalDialog Confirm_md =   new ConfirmModalDialog(name, owner_stg, parent); 
                
            }
        });
	
	tf.setOnAction(new EventHandler<ActionEvent>() {

            public void handle(ActionEvent event) {
	      String name2 = tf.getText();
              parent.setText_TextArea(name2);
	      tf.deleteText(0, name2.length());
            }
        });
         
        label.setPrefWidth(200.0);
        label.setLayoutX((scene.getWidth() -200.0) / 2 );
       
        btn.setPrefWidth(50.0);
        btn.setLayoutX((scene.getWidth() -50.0) / 2 );
        label.setLayoutY(scene.getHeight() / 3);     
        btn.setLayoutY(scene.getHeight() / 2);
        btn.setText("OK");
	
	tf.setPrefColumnCount(30);
	tf.setLayoutX((scene.getWidth() -330.0) / 2 );
        tf.setLayoutY(scene.getHeight() / 2 + 50);
       
        root.getChildren().addAll(label, btn, tf);   
        stage.setScene(scene); 
        stage.setResizable(false);       
        stage.show();
 
    }
    
}

ModalTest.java

import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.scene.Group;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.TextArea;
import javafx.scene.paint.Color;
import javafx.stage.Stage;
 
 
public class ModalTest extends Application {
 
    private TextArea ta;
    
    public static void main(String[] args) {
        Application.launch(ModalTest.class, args);
    }
    
    @Override
    public void start(final Stage primaryStage) {
    
        final ModalTest mt = this;
        primaryStage.setTitle("Modal Test");
        Group root = new Group();
        Scene scene = new Scene(root, 500, 450, Color.LIGHTBLUE);
        Button btn = new Button();
        ta = new TextArea();
	ta.setPrefColumnCount(40);
	ta.setPrefRowCount(22);
	ta.setLayoutX(20);
        ta.setLayoutY(10);
        btn.setLayoutX(200);
        btn.setLayoutY(400);
        btn.setText("Show dialog");
        btn.setOnAction(new EventHandler<ActionEvent>() {
 
            public void handle(ActionEvent event) {
	       
                ModalDialog   md =   new ModalDialog(primaryStage, mt);
             
            }
        });
        root.getChildren().addAll(ta, btn);        
        primaryStage.setScene(scene);
	primaryStage.setResizable(false);
        primaryStage.show();
    }
    
    public void setText_TextArea(String s){
       ta.appendText(s + "\n");
       }
}

ConfirmModalDialog.java

import javafx.stage.*; 
import javafx.scene.*;
import javafx.scene.paint.Color;
import javafx.scene.control.*;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
 
public class ConfirmModalDialog {

      private Label label;
      private Button btn;
      private Button yes_btn;
      private Button no_btn;
      private ModalTest parent;
    
    public ConfirmModalDialog(final String name, final Stage owner_stg, ModalTest mt) {
        
	   parent = mt;
           label = new Label(name + ", do you like \"JavaFX\" ?");
	   yes_btn = new Button();
	   no_btn = new Button();
	   final TextField tf = new TextField();
         
           final  Stage stage = new Stage();   
	
        //Initialize the Stage with type of modal
	   stage.initModality(Modality.WINDOW_MODAL);
	
        //Set the owner of the Stage 
           stage.initOwner(owner_stg);
           stage.setTitle("Confirm Dialog Stage");
           Group root = new Group();
           Scene scene = new Scene(root, 380, 250, Color.web("#0000FF", 0.3));
	    
	    yes_btn.setOnAction(new EventHandler<ActionEvent>() {
 
            public void handle(ActionEvent event) {
	    
	     parent.setText_TextArea(tf.getText());
	     parent.setText_TextArea(name + " , Cool !");
             stage.hide();
	    Messege_ModalDialog y_md =   new Messege_ModalDialog(name, "yes", owner_stg, parent);
                
            } });
	    
	    no_btn.setOnAction(new EventHandler<ActionEvent>() {
 
            public void handle(ActionEvent event) {
	    
	     parent.setText_TextArea(tf.getText());
	     parent.setText_TextArea(name + " , Bad Boy !");
            // stage.hide();
	     stage.close();
	   Messege_ModalDialog n_md =   new Messege_ModalDialog(name, "no", owner_stg, parent);
                
            } });
	
	tf.setOnAction(new EventHandler<ActionEvent>() {

            public void handle(ActionEvent event) {
	       String s2 = tf.getText();
               parent.setText_TextArea(s2);
	       tf.deleteText(0, s2.length());
            }
        });
         
        label.setPrefWidth(300.0);
        label.setLayoutX((scene.getWidth() - 300.0) / 2 );
       
        yes_btn.setPrefWidth(50.0);
        yes_btn.setLayoutX((scene.getWidth() -50.0) / 3 );
       
        no_btn.setPrefWidth(50.0);
        no_btn.setLayoutX((scene.getWidth() -50.0) / 3 * 2 );
        label.setLayoutY(scene.getHeight() / 3);
	
	yes_btn.setLayoutY(scene.getHeight() / 2);
        yes_btn.setText("YES");
	
	no_btn.setLayoutY(scene.getHeight() / 2);
        no_btn.setText("NO");
	
	tf.setPrefColumnCount(30);
	tf.setLayoutX((scene.getWidth() -330.0) / 2 );
        tf.setLayoutY(scene.getHeight() / 2 + 50);
       
        root.getChildren().addAll(label, yes_btn, no_btn, tf);   
        stage.setScene(scene); 
        stage.setResizable(false);       
        stage.show();
 
    }
    
 }

Messege_ModalDialog.java

import javafx.stage.*; 
import javafx.scene.*;
import javafx.scene.paint.Color;
import javafx.scene.control.*;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
 
public class Messege_ModalDialog {

     private Label label = new Label();
     private Button btn;
     private ModalTest parent;
    
    public Messege_ModalDialog(String name, String s, final Stage owner_stg, ModalTest mt) {
        
	 parent = mt;
       
       if(s.equals("yes")){
        label.setText(name + " , Cool !");
	}else{
	label.setText(name + " , Bad Boy !");
	}
	btn = new Button("OK");
	
	final TextField tf = new TextField();
         
    final  Stage stage = new Stage();    
       
        //Initialize the Stage with type of modal
	 stage.initModality(Modality.WINDOW_MODAL);
	
        //Set the owner of the Stage 
         stage.initOwner(owner_stg);
         stage.setTitle("Messege Dialog Stage");
         Group root = new Group();
         Scene scene = new Scene(root, 380, 250, Color.web("#0000FF", 0.3));
	    
	    btn.setOnAction(new EventHandler<ActionEvent>() {
 
            public void handle(ActionEvent event) {
	    
	     parent.setText_TextArea(tf.getText());
	     parent.setText_TextArea("OK");
           //  stage.hide();
	     stage.close();
                
            } });
	
	     tf.setOnAction(new EventHandler<ActionEvent>() {

            public void handle(ActionEvent event) {
	      String s2  = tf.getText();
              parent.setText_TextArea(s2);
	      tf.deleteText(0, s2.length());
            }
        });
         
       label.setPrefWidth(200.0);
       label.setLayoutX((scene.getWidth() -200.0) / 2);
       
       btn.setPrefWidth(50.0);
       btn.setLayoutX((scene.getWidth() - 50.0) / 2 );
       
        label.setLayoutY(scene.getHeight() / 3);
	
	btn.setLayoutY(scene.getHeight() / 2);
	
	tf.setPrefColumnCount(30);
	tf.setLayoutX((scene.getWidth() -330.0) / 2 );
        tf.setLayoutY(scene.getHeight() / 2 + 50);
       
        root.getChildren().addAll(label, btn, tf);   
        stage.setScene(scene); 
        stage.setResizable(false);       
        stage.show();
 
    
    }
    
}