JavaFx 2按钮2 Listner 1结果

Question

我的小应用程序包含2个按钮，每个按钮都有一个addActionListener入口和其他东西但是使用哪个监听器？ 我后来添加到事件处理程序的那个，但为什么？

以下是我的代码的一些代码：

public class LoginStarter extends Application {

public static void main(String[] args) {
    // TODO Auto-generated method stub

    launch(args);
}

@Override
public void start(Stage primaryStage) {

    TextField usernameField = new TextField();
    usernameField.setLayoutX(426);
    usernameField.setLayoutY(230);
    usernameField.setPromptText("Username");
    usernameField.setMinSize(148, 24);
    usernameField.setMaxSize(148, 24);
    PasswordField passwordField = new PasswordField();
    passwordField.setLayoutX(426);
    passwordField.setLayoutY(260);
    passwordField.setMinSize(148, 24);
    passwordField.setMaxSize(148, 24);
    passwordField.setPromptText("Password");
    Pane gp = new Pane();
    gp.getChildren().add(minimiseBtn());
    gp.getChildren().add(xBtn());
    gp.getChildren().add(usernameField);
    gp.getChildren().add(passwordField);
    gp.setId("pane");

    Scene scene = new Scene(gp, 1000, 550);
    scene.getStylesheets().addAll(
            this.getClass().getResource("gui.css").toExternalForm());
    primaryStage.initStyle(StageStyle.UNDECORATED);
    primaryStage.setTitle("Corp Commander v0.0.1");
    primaryStage.setScene(scene);
    primaryStage.show();

}

public Button minimiseBtn() {

    Button minimiseBtn = new Button();
    minimiseBtn.setText("");
    minimiseBtn.setMaxSize(20, 20);
    minimiseBtn.setMinSize(20, 20);
    minimiseBtn.setId("minimiseBtn");
    minimiseBtn.setLayoutX(956);
    minimiseBtn.setLayoutY(2);
    minimiseBtn.setOnAction(minimiseBtnListener());

    return minimiseBtn;

}

private EventHandler<ActionEvent> minimiseBtnListener() {
    EventHandler<ActionEvent> eh = new EventHandler<ActionEvent>() {

        @Override
        public void handle(ActionEvent arg0) {
            System.out.println("minimise");

        }
    };
    return eh;
}
public Button xBtn() {
    Button xBtn = new Button();
    xBtn.setText("");
    xBtn.setMaxSize(20, 20);
    xBtn.setMinSize(20, 20);
    xBtn.setId("xBtn");
    xBtn.setLayoutX(978);
    xBtn.setLayoutY(2);

    xBtn.setOnAction(xbtnListener());

    return xBtn;
}

private EventHandler<ActionEvent> xbtnListener() {
    EventHandler<ActionEvent> eh = new EventHandler<ActionEvent>() {

        @Override
        public void handle(ActionEvent arg0) {
            System.out.println("exit");
            System.exit(0);

        }
    };
    return eh;
}
}

此CSS用于：

 @CHARSET "ISO-8859-1";
 #pane{
-fx-background-image: url("background_image.jpg");
-fx-background-repeat: stretch;   
-fx-background-size: 1000 550;
-fx-background-position: center center;
-fx-effect: dropshadow(three-pass-box, black, 30, 0.5, 0, 0); 
 opacity: 0.95;
}

#xBtn{
-fx-background-image: url("exitBtn2.png");
-fx-background-repeat: stretch;   
-fx-background-size: 20 20;
-fx-background-position: center center;
-fx-effect: dropshadow(three-pass-box, black, 30, 0.5, 0, 0);
-fx-background-color: transparent;
}

#minimiseBtn{
-fx-background-image: url("minusBtn2.png");
-fx-background-repeat: stretch;   
-fx-background-size: 20 20;
-fx-background-position: center center;
-fx-effect: dropshadow(three-pass-box, black, 30, 0.5, 0, 0);
-fx-background-color: transparent;
}