在Javafx 2.0中拖放事件

我正在使用javafx 2.0和netbean 7.1，在通過ImageView拖放圖像時遇到了問題，.i將圖像保存爲源（一個圖像）和2個目標點（2個盒子作爲目標點）。當第一次嘗試拖動圖像時，它的工作正常，並且在源圖像輸入到目標box.and後再次嘗試拖動圖像，下面的錯誤被修改爲「java.lang .IllegalArgumentException：錯誤的字節緩衝區大小18x15 [1080]！= 0「在Javafx 2.0中拖放事件

一旦圖像移動到目標對象，我需要設置偵聽器將其更改爲源，我覺得它在這個地方拋出錯誤..

正在使用的代碼

public class DragandDropEx extends Application { 

    /** 
    * @param args the command line arguments 
    */ 
    GridPane Board; 
    ImageView deactivateImageView = new ImageView(); 
    ImageView newImageView = new ImageView(); 




    final Rectangle target = new Rectangle(0, 0, 50, 50); 
    final Rectangle target2 = new Rectangle(0, 0, 50, 50); 


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

    @Override 
    public void start(Stage primaryStage) { 
     target.setFill(Color.CHOCOLATE); 
     target2.setFill(Color.BLUE); 
     Image image = new Image(getClass().getResourceAsStream("triangle.png")); 
     getDeactivateImageView().setImage(image); 
     Board = new GridPane(); 
     primaryStage.setTitle("Drag and Drop"); 



     createSource(getDeactivateImageView()); 



     target.setOnDragOver(new EventHandler<DragEvent>() { 

      @Override 
      public void handle(DragEvent events) { 
       events.acceptTransferModes(TransferMode.MOVE); 
       events.consume(); 

        createTargetDrop(target,0,8); 
      } 
     }); 
     target2.setOnDragOver(new EventHandler<DragEvent>() { 

      @Override 
      public void handle(DragEvent events) { 
       events.acceptTransferModes(TransferMode.MOVE); 
       events.consume(); 
       createTargetDrop(target2,0,9); 
      } 
     }); 






     Board.add(getDeactivateImageView(), 0, 1); 
     Board.add(target, 0, 8); 
     Board.add(target2, 0, 9); 

     StackPane root = new StackPane(); 
     root.getChildren().add(Board); 
     primaryStage.setScene(new Scene(root, 300, 250)); 
     primaryStage.show(); 
    } 

    private void createSource(final ImageView imageView) { 
     imageView.setOnDragDetected(new EventHandler<MouseEvent>() { 
      @Override 
      public void handle(MouseEvent events) { 
       Dragboard storeImage =imageView.startDragAndDrop(TransferMode.MOVE); 
       ClipboardContent content = new ClipboardContent(); 
       content.putImage(imageView.getImage()); 
       storeImage.setContent(content);      **// here i am getting error** 
       events.consume(); 


      } 
     }); 
    } 

    private void createTargetDrop(final Rectangle target,final int xCordination,final int yCordination) { 

     target.setOnDragDropped(new EventHandler<DragEvent>() { 

      @Override 
      public void handle(DragEvent event) { 
       Dragboard db = event.getDragboard(); 
       Image dragedImage = db.getImage(); 
       getNewImageView().setImage(dragedImage); 
       getDeactivateImageView().setVisible(false); 
       setDeactivateImageView(getNewImageView()); 
       Board.add(getDeactivateImageView(),xCordination,yCordination); 
       event.consume(); 
       createSource(getDeactivateImageView());           // setting listener to new image 

      } 
     }); 

    } 
}

來源

2012-03-07 karthik selvaraj