如何在控制器类中引用Stage？ [英] How to reference Stage in controller class?

问题描述

Main.class

Main.class

public class Main extends Application {
    @Override
    public void start(Stage primaryStage) {
        try {
            Parent root = FXMLLoader.load(getClass().getResource("/application/Main.fxml"));
            Scene scene = new Scene(root);
            scene.getStylesheets().add(getClass().getResource("application.css").toExternalForm());
            primaryStage.setScene(scene);
            primaryStage.show();
        } catch(Exception e) {
            e.printStackTrace();
        }
    }

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

MainController.class

MainController.class

    public class MainController implements Initializable {

    @FXML private MediaView mv;
    private MediaPlayer mp;
    private Media me;

    @FXML Slider volumeSlider;

    DoubleProperty width;
    DoubleProperty height;

    Stage stage;

    @Override
    public void initialize(URL location, ResourceBundle resources) {
        // TODO Auto-generated method stub
        String path = new File("src/media/my.mp4").getAbsolutePath();
        me = new Media(new File(path).toURI().toString());
        mp = new MediaPlayer(me);
        mv.setMediaPlayer(mp);
        //mp.setAutoPlay(true);

        stage = (Stage) mv.getScene().getWindow();  // Error occured

        width = mv.fitWidthProperty();
        height = mv.fitHeightProperty();
        width.bind(Bindings.selectDouble(mv.sceneProperty(), "width"));
        height.bind(Bindings.selectDouble(mv.sceneProperty(), "height"));

        volumeSlider.setValue(mp.getVolume() * 100);
        volumeSlider.valueProperty().addListener(new InvalidationListener() {

            @Override
            public void invalidated(Observable observable) {
                // TODO Auto-generated method stub
                mp.setVolume(volumeSlider.getValue() / 100);
            }
        });
    }

    public void play(ActionEvent event){
        mp.play();
        mp.setRate(1);
    }
    public void pause(ActionEvent event){
        mp.pause();
    }
    public void fast(ActionEvent event){
        mp.setRate(2);
    }
    public void slow(ActionEvent event){
        mp.setRate(.5);
    }
    public void reload(ActionEvent event){
        mp.seek(mp.getStartTime());
        mp.play();
    }
    public void start(ActionEvent event){
        mp.seek(mp.getStartTime());
        mp.stop();
    }
    public void last(ActionEvent event){
        mp.seek(mp.getTotalDuration());
        mp.stop();
    }
    public void fullScreen(ActionEvent event){

    }
}

错误

Error

javafx.fxml.LoadException: 
/C:/Users/SOONMYUN/workspace/MediaPlayer/bin/application/Main.fxml

    at javafx.fxml.FXMLLoader.constructLoadException(FXMLLoader.java:2601)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:2579)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:2441)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3214)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3175)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3148)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3124)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3104)
    at javafx.fxml.FXMLLoader.load(FXMLLoader.java:3097)
    at application.Main.start(Main.java:17)
    at com.sun.javafx.application.LauncherImpl.lambda$launchApplication1$162(LauncherImpl.java:863)
    at com.sun.javafx.application.PlatformImpl.lambda$runAndWait$175(PlatformImpl.java:326)
    at com.sun.javafx.application.PlatformImpl.lambda$null$173(PlatformImpl.java:295)
    at java.security.AccessController.doPrivileged(Native Method)
    at com.sun.javafx.application.PlatformImpl.lambda$runLater$174(PlatformImpl.java:294)
    at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:95)
    at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
    at com.sun.glass.ui.win.WinApplication.lambda$null$148(WinApplication.java:191)
    at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.NullPointerException
    at application.MainController.initialize(MainController.java:44)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:2548)
    ... 17 more

我想从主课程到舞台控制器类，但失败了。

I want to get the Stage from Main class to Controller class but it was failed.

因为我应该在Controller类中使用setFullScreen函数。

Because I should use the setFullScreen function in Controller class.

推荐答案

我正在回答如何将阶段对象从主类传递到控制器类
在控制器类中创建一个函数

i am answering how to pass stage object from main class to your controller class create a function in your controller class

public void setStage(Stage stage){
this.stage=stage;
}

现在在你的主类中调用这个函数，就像这样

now call this function in your main class like this

 FXMLLoader fxmlLoader = new FXMLLoader(getClass().getResource("/application/Main.fxml"));
                Parent root = (Parent) fxmlLoader.load();
  ((MainController) fxmlLoader.getController()).setStage(primaryStage);

如果你想获得舞台对象而不将它从主类传递到类到控制器类你可以做这样

if you want to get the stage object without passing it from main to class to controller class you can do this way

1.给你的AnchorPane ID，例如 fx：id =ap然后在您的Controller类中

1.Give id to your AnchorPane e.g. fx:id="ap" then in your Controller class

@FXML
AnchorPane ap;

2.你想要的对象

Stage stage = (Stage) ap.getScene.getWindow();

这篇关于如何在控制器类中引用Stage？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！