E HelloDragAndDrop.java

有关描述，请参见实现基本的拖放手势。

法律条款和版权声明

/*
 * 版权所有 (c) 2011, 2014, Oracle及其附属公司。
 * 保留所有权利。使用受许可条款约束。
 *
 * 此文件可在以下许可下使用和许可：
 *
 * 源代码的重新发布和使用，无论是否进行修改，只要满足以下条件：
 *
 *  - 必须保留上述版权声明、此条件列表和以下免责声明。
 *  - 以二进制形式重新发布的代码必须在文档和/或其他提供的材料中复制上述版权声明、此条件列表和以下免责声明。
 *  - 未经特定事先书面许可，不得使用Oracle或其贡献者的名称来认可或推广从本软件派生的产品。
 *
 * 本软件由版权持有人和贡献者“按原样”提供，不提供任何明示或暗示的保证，包括但不限于适销性和适用性的暗示保证。
 * 在任何情况下，版权所有者或贡献者均不对任何直接、间接、偶然、特殊、惩罚性或后果性损害（包括但不限于替代商品或服务的采购、使用损失、数据或利润损失、业务中断）承担任何责任，无论是合同责任、严格责任还是侵权行为（包括疏忽或其他）。
 */

代码

package hellodraganddrop;
 
import javafx.application.Application;
import javafx.event.EventHandler;
import javafx.scene.Group;
import javafx.scene.Scene;
import javafx.scene.input.*;
import javafx.scene.paint.Color;
import javafx.scene.text.Text;
import javafx.stage.Stage;
 
/**
 * Demonstrates a drag-and-drop feature.
 */
public class HelloDragAndDrop extends Application {
 
    @Override 
    public void start(Stage stage) {
        stage.setTitle("Hello Drag And Drop");
 
        Group root = new Group();
        Scene scene = new Scene(root, 400, 200);
        scene.setFill(Color.LIGHTGREEN);
 
        final Text source = new Text(50, 100, "DRAG ME");
        source.setScaleX(2.0);
        source.setScaleY(2.0);
 
        final Text target = new Text(250, 100, "DROP HERE");
        target.setScaleX(2.0);
        target.setScaleY(2.0);
 
        source.setOnDragDetected(new EventHandler <MouseEvent>() {
            @Override
            public void handle(MouseEvent event) {
                /* drag was detected, start drag-and-drop gesture*/
                System.out.println("onDragDetected");
                
                /* allow MOVE transfer mode */
                Dragboard db = source.startDragAndDrop(TransferMode.MOVE);
                
                /* put a string on dragboard */
                ClipboardContent content = new ClipboardContent();
                content.putString(source.getText());
                db.setContent(content);
                
                event.consume();
            }
        });
 
        target.setOnDragOver(new EventHandler <DragEvent>() {
            @Override
            public void handle(DragEvent event) {
                /* data is dragged over the target */
                System.out.println("onDragOver");
                
                /* accept it only if it is  not dragged from the same node 
                 * and if it has a string data */
                if (event.getGestureSource() != target &&
                        event.getDragboard().hasString()) {
                    /* allow for moving */
                    event.acceptTransferModes(TransferMode.MOVE);
                }
                
                event.consume();
            }
        });
 
        target.setOnDragEntered(new EventHandler <DragEvent>() {
            @Override
            public void handle(DragEvent event) {
                /* the drag-and-drop gesture entered the target */
                System.out.println("onDragEntered");
                /* show to the user that it is an actual gesture target */
                if (event.getGestureSource() != target &&
                        event.getDragboard().hasString()) {
                    target.setFill(Color.GREEN);
                }
                
                event.consume();
            }
        });
 
        target.setOnDragExited(new EventHandler <DragEvent>() {
            @Override
            public void handle(DragEvent event) {
                /* mouse moved away, remove the graphical cues */
                target.setFill(Color.BLACK);
                
                event.consume();
            }
        });
        
        target.setOnDragDropped(new EventHandler <DragEvent>() {
            @Override
            public void handle(DragEvent event) {
                /* data dropped */
                System.out.println("onDragDropped");
                /* if there is a string data on dragboard, read it and use it */
                Dragboard db = event.getDragboard();
                boolean success = false;
                if (db.hasString()) {
                    target.setText(db.getString());
                    success = true;
                }
                /* let the source know whether the string was successfully 
                 * transferred and used */
                event.setDropCompleted(success);
                
                event.consume();
            }
        });
 
        source.setOnDragDone(new EventHandler <DragEvent>() {
            @Override
            public void handle(DragEvent event) {
                /* the drag-and-drop gesture ended */
                System.out.println("onDragDone");
                /* if the data was successfully moved, clear it */
                if (event.getTransferMode() == TransferMode.MOVE) {
                    source.setText("");
                }
                
                event.consume();
            }
        });
 
        root.getChildren().add(source);
        root.getChildren().add(target);
        stage.setScene(scene);
        stage.show();
    }
 
    public static void main(String[] args) {
        Application.launch(args);
    }
}