Question

我正在尝试使用JavaFX构建媒体播放器。首先，我加载了一个视频，接下来我创建了一个暂停按钮，工作正常。当我用打开的按钮加载新视频时（＆＃34; apri＆＃34;）视频正常工作，但暂停按钮无法正常工作-_-这是我的主要课程..我没有使用过场景制作者，但我只尝试使用代码

public class Main extends Application {

public String indirizzo = "file:///C:/Users/ASUS/Desktop/film/prova1.mp4";

@Override
public void start(Stage primaryStage) {
    try {
        /* Creo la scena e mi faccio passare il media da visualizzare */

        /* Creo i pannelli */
        BorderPane bp = new BorderPane();
        StackPane sp = new StackPane();
        HBox hb = new HBox(5);
        VBox vb = new VBox();

        /* Primo video */
        MediaView mv = new MediaView();
        Media m = new Media(indirizzo);
        MediaPlayer mp = new MediaPlayer(m);
        mv.setMediaPlayer(mp);
        mp.play();

        /* Creo gli oggetti nella parte bassa*/
        Slider misc = new Slider();
        Slider sl = new Slider();
        Label volume = new Label("Volume: ");

        Button btn1 = new Button("Apri");
        Button btn2 = new Button("<<");
        Button btn3 = new Button("| |");
        Button btn4 = new Button(">>");

        hb.setAlignment(Pos.CENTER);
        hb.setPadding(new Insets(5,10,5,10));
        /* Dimensioni slider */
        sl.setPrefWidth(70);
        sl.setMinWidth(30);
        sl.setValue(100);

        /* Posiziono i pannelli */
        bp.setCenter(mv);
        hb.getChildren().addAll(btn1,btn2,btn3,btn4,volume,sl);


        vb.getChildren().addAll(misc,hb);
        bp.setBottom(vb);


        /* Se schiaccio il pulsante apri */
        btn1.setOnAction(new EventHandler<ActionEvent>() {
                @Override public void handle(ActionEvent e) {

                    /* Prima metto in pausa il video */

                    FileChooser fc = new FileChooser();
                    ExtensionFilter filtro = new ExtensionFilter("Seleziona media (*.mp4)","*.mp4");
                    fc.getExtensionFilters().add(filtro);

                    /* Apro la finestra di dialogo per caricare il file */
                    File file = fc.showOpenDialog(null);
                    indirizzo = file.toURI().toString();

                    if(file != null){
                        /* Carico il media nel mp */
                        Media m = new Media(indirizzo);

                        MediaPlayer mp = new MediaPlayer(m);
                        mv.setMediaPlayer(mp);
                        /* Imposto dimensione Media View*/
                        mv.setFitHeight(500);   /* Vanno bindate con la scene*/
                        mv.setFitWidth(500);
                        mp.play();

                        DoubleProperty mvw = mv.fitWidthProperty();
                        DoubleProperty mvh = mv.fitHeightProperty();
                        mvw.bind(Bindings.selectDouble(mv.sceneProperty(), "width"));
                        mvh.bind(Bindings.selectDouble(mv.sceneProperty(), "height"));
                        mv.setPreserveRatio(true);


                    }

                }
            });

        btn3.setOnAction((ActionEvent e) -> {
            Status currentStatus = mp.getStatus();

            if(currentStatus == Status.PLAYING)
                mp.pause();
            else if(currentStatus == Status.PAUSED || currentStatus == Status.STOPPED){
                mp.play();
            }

        });


        Scene scena = new Scene(bp,500,500);
        scena.getStylesheets().add(getClass().getResource("application.css").toExternalForm());
        primaryStage.setScene(scena);
        primaryStage.show();
    } catch(Exception e) {
        e.printStackTrace();
    }
}

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

Answer 1

问题在于：

               if(file != null){
                    /* Carico il media nel mp */
                    Media m = new Media(indirizzo);

                    MediaPlayer mp = new MediaPlayer(m);

您正在使用mp处理程序无法看到的新变量btn3.setOnAction()。

要解决这个问题，请MediaPlayer mp一个班级＆＃39;字段并且不要使用mp名称引入新变量。

暂停问题JavaFX

1 个答案: