拖放后移动组件 [英] move component after drag and drop
本文介绍了拖放后移动组件的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
我见过 code拖放。
问题1：如何才能移动图像（使用鼠标）内下跌后面板的图像将被丢弃。 （图像的目的，我想在这里，我松开鼠标，然后（使用鼠标会更好，或使用按钮来改变位置太 - 。但使用鼠标更好）
Question1: how can we move image inside dropped panel (using mouse pointer) after image will be dropped. (destination of image, I want to be where where I release mouse. and then to change location too (using mouse will be better. or using buttons - but using mouse is better)
问题2：我怎么能放弃结束后改变位置
Question2: how can I change location after dropping end?
P.S我想在这里形象的组成部分。
p.s I want here image to component.
首先，我拖放组件。然后用鼠标指针（移动）改变位置。
first I drag and drop component. then change location using mouse pointer (move it).
这里是code：
import java.awt.BorderLayout;
import java.awt.EventQueue;
import java.awt.GridBagLayout;
import java.awt.datatransfer.DataFlavor;
import java.awt.datatransfer.Transferable;
import java.awt.datatransfer.UnsupportedFlavorException;
import java.awt.dnd.DnDConstants;
import java.awt.dnd.DragGestureEvent;
import java.awt.dnd.DragGestureListener;
import java.awt.dnd.DragGestureRecognizer;
import java.awt.dnd.DragSource;
import java.awt.dnd.DragSourceDragEvent;
import java.awt.dnd.DragSourceDropEvent;
import java.awt.dnd.DragSourceEvent;
import java.awt.dnd.DragSourceListener;
import java.awt.dnd.DropTarget;
import java.awt.dnd.DropTargetDragEvent;
import java.awt.dnd.DropTargetDropEvent;
import java.awt.dnd.DropTargetEvent;
import java.awt.dnd.DropTargetListener;
import java.io.IOException;
import javax.swing.DefaultListModel;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JList;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class TestDnD {
public static void main(String[] args) {
new TestDnD();
}
public TestDnD() {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException ex) {
} catch (InstantiationException ex) {
} catch (IllegalAccessException ex) {
} catch (UnsupportedLookAndFeelException ex) {
}
JFrame frame = new JFrame("Test");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
private JList list;
public TestPane() {
setLayout(new BorderLayout());
list = new JList();
DefaultListModel model = new DefaultListModel();
model.addElement(new User("Shaun"));
model.addElement(new User("Andy"));
model.addElement(new User("Luke"));
model.addElement(new User("Han"));
model.addElement(new User("Liea"));
model.addElement(new User("Yoda"));
list.setModel(model);
add(new JScrollPane(list), BorderLayout.WEST);
DragGestureRecognizer dgr = DragSource.getDefaultDragSource().createDefaultDragGestureRecognizer(
list,
DnDConstants.ACTION_COPY_OR_MOVE,
new DragGestureHandler(list));
JPanel panel = new JPanel(new GridBagLayout());
add(panel);
DropTarget dt = new DropTarget(
panel,
DnDConstants.ACTION_COPY_OR_MOVE,
new DropTargetHandler(panel),
true);
}
}
public static class User {
private String name;
public User(String name) {
this.name = name;
}
public String getName() {
return name;
}
@Override
public String toString() {
return name;
}
}
public static class UserTransferable implements Transferable {
public static final DataFlavor USER_DATA_FLAVOR = new DataFlavor(User.class, "User");
private User user;
public UserTransferable(User user) {
this.user = user;
}
@Override
public DataFlavor[] getTransferDataFlavors() {
return new DataFlavor[]{USER_DATA_FLAVOR};
}
@Override
public boolean isDataFlavorSupported(DataFlavor flavor) {
return USER_DATA_FLAVOR.equals(flavor);
}
@Override
public Object getTransferData(DataFlavor flavor) throws UnsupportedFlavorException, IOException {
Object value = null;
if (USER_DATA_FLAVOR.equals(flavor)) {
value = user;
} else {
throw new UnsupportedFlavorException(flavor);
}
return value;
}
}
protected class DragGestureHandler implements DragGestureListener {
private JList list;
public DragGestureHandler(JList list) {
this.list = list;
}
@Override
public void dragGestureRecognized(DragGestureEvent dge) {
Object selectedValue = list.getSelectedValue();
if (selectedValue instanceof User) {
User user = (User) selectedValue;
Transferable t = new UserTransferable(user);
DragSource ds = dge.getDragSource();
ds.startDrag(dge, null, t, new DragSourceHandler());
}
}
}
protected class DragSourceHandler implements DragSourceListener {
public void dragEnter(DragSourceDragEvent dsde) {
}
public void dragOver(DragSourceDragEvent dsde) {
}
public void dropActionChanged(DragSourceDragEvent dsde) {
}
public void dragExit(DragSourceEvent dse) {
}
public void dragDropEnd(DragSourceDropEvent dsde) {
System.out.println("Drag ended...");
}
}
protected class DropTargetHandler implements DropTargetListener {
private JPanel panel;
public DropTargetHandler(JPanel panel) {
this.panel = panel;
}
public void dragEnter(DropTargetDragEvent dtde) {
if (dtde.getTransferable().isDataFlavorSupported(UserTransferable.USER_DATA_FLAVOR)) {
System.out.println("Accept...");
dtde.acceptDrag(DnDConstants.ACTION_COPY_OR_MOVE);
} else {
System.out.println("Drag...");
dtde.rejectDrag();
}
}
public void dragOver(DropTargetDragEvent dtde) {
}
public void dropActionChanged(DropTargetDragEvent dtde) {
}
public void dragExit(DropTargetEvent dte) {
}
public void drop(DropTargetDropEvent dtde) {
System.out.println("Dropped...");
if (dtde.getTransferable().isDataFlavorSupported(UserTransferable.USER_DATA_FLAVOR)) {
Transferable t = dtde.getTransferable();
if (t.isDataFlavorSupported(UserTransferable.USER_DATA_FLAVOR)) {
try {
Object transferData = t.getTransferData(UserTransferable.USER_DATA_FLAVOR);
if (transferData instanceof User) {
User user = (User) transferData;
dtde.acceptDrop(DnDConstants.ACTION_COPY_OR_MOVE);
panel.add(new JLabel(user.getName()));
panel.revalidate();
panel.repaint();
} else {
dtde.rejectDrop();
}
} catch (UnsupportedFlavorException ex) {
ex.printStackTrace();
dtde.rejectDrop();
} catch (IOException ex) {
ex.printStackTrace();
dtde.rejectDrop();
}
} else {
dtde.rejectDrop();
}
}
}
}
}
推荐答案
这是一个实现拖动，基本上是两个像窗格之间的图片。
This is a implementation of dragging, essentially, images between two like panes.
如果你打算在不允许组件的运动的限制扔 S，你要与确保源和目标容器知道被卡住如何处理拖放（和渲染的结果）
If you're going to throw in the restriction of not allowing the movement of Components, you are going to be stuck with ensure that the source and target containers know how to handle the drag and drop (and render the results)
这已经采取了更好的一部分，4个小时，所以你锤我的更新请求之前，请确保您所做的努力，以了解code和实施自己的更改
This has taken the better part 4 hours, so before you hammer me with update requests, make sure you've made the effort to understand the code and implemented your own changes
实施包装了图片在拖动图像类，维护有关其容器内图像的位置信息，这个用来生产拖动图像...
The implementation wraps the Image in a DragImage class, that maintains information about the image's location within its container, this used to produce the drag image...
import java.awt.AlphaComposite;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.GridLayout;
import java.awt.Image;
import java.awt.Point;
import java.awt.Rectangle;
import java.awt.datatransfer.DataFlavor;
import java.awt.datatransfer.Transferable;
import java.awt.datatransfer.UnsupportedFlavorException;
import java.awt.dnd.DnDConstants;
import java.awt.dnd.DragGestureEvent;
import java.awt.dnd.DragGestureListener;
import java.awt.dnd.DragGestureRecognizer;
import java.awt.dnd.DragSource;
import java.awt.dnd.DragSourceDragEvent;
import java.awt.dnd.DragSourceDropEvent;
import java.awt.dnd.DragSourceEvent;
import java.awt.dnd.DragSourceListener;
import java.awt.dnd.DropTarget;
import java.awt.dnd.DropTargetDragEvent;
import java.awt.dnd.DropTargetDropEvent;
import java.awt.dnd.DropTargetEvent;
import java.awt.dnd.DropTargetListener;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import javax.imageio.ImageIO;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
import javax.swing.border.EmptyBorder;
import javax.swing.border.LineBorder;
public class TestDnD {
public static void main(String[] args) {
new TestDnD();
}
public TestDnD() {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
try {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException ex) {
} catch (InstantiationException ex) {
} catch (IllegalAccessException ex) {
} catch (UnsupportedLookAndFeelException ex) {
}
JFrame frame = new JFrame("Test");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new GridLayout(0, 2, 10, 10));
((JComponent) frame.getContentPane()).setBorder(new EmptyBorder(10, 10, 10, 10));
BufferedImage img = ImageIO.read(new File("issue376.jpg"));
ImagePane imagePane = new ImagePane();
imagePane.addImage(img);
frame.add(imagePane);
frame.add(new ImagePane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
} catch (IOException ex) {
ex.printStackTrace();
System.exit(0);
}
}
});
}
public class ImagePane extends JPanel {
private List<DragImage> images;
private DragImages dropImages;
private Point dragPoint;
public ImagePane() {
setBorder(new LineBorder(Color.GRAY));
images = new ArrayList<>(25);
DragGestureRecognizer dgr = DragSource.getDefaultDragSource().createDefaultDragGestureRecognizer(
this,
DnDConstants.ACTION_COPY_OR_MOVE,
new DragGestureHandler(this));
DropTarget dt = new DropTarget(
this,
DnDConstants.ACTION_COPY_OR_MOVE,
new DropTargetHandler(this),
true);
}
@Override
public Dimension getPreferredSize() {
return new Dimension(200, 200);
}
public DragImage getImageAt(Point p) {
DragImage at = null;
for (DragImage di : images) {
if (di.contains(p)) {
at = di;
break;
}
}
return at;
}
protected boolean contains(Image image) {
boolean contains = false;
for (DragImage di : images) {
if (di.getImage() == image) {
contains = true;
break;
}
}
return contains;
}
public void addImage(Image image) {
if (image != null) {
if (!contains(image)) {
int x = (int) Math.round(Math.random() * getWidth());
int y = (int) Math.round(Math.random() * getHeight());
addImageAt(new Point(x, y), image);
}
}
}
public void addImageAt(Point p, Image image) {
if (p != null && image != null) {
if (!contains(image)) {
DragImage di = new DragImage(image, p);
images.add(di);
repaint();
}
}
}
@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
for (DragImage di : images) {
g2d.drawImage(di.getImage(), di.getLocation().x, di.getLocation().y, this);
}
if (dropImages != null) {
g2d.setComposite(AlphaComposite.SrcOver.derive(0.5f));
Point offset = dropImages.getOffset();
for (DragImage di : dropImages.getImages()) {
Point pp = new Point(dragPoint);
pp.x -= offset.getX();
pp.y -= offset.getY();
g2d.drawImage(di.getImage(), pp.x, pp.y, this);
}
}
g2d.dispose();
}
public void removeImages(List list) {
if (list != null && list.size() > 0) {
for (Object obj : list) {
if (obj instanceof DragImage) {
removeImage((DragImage) obj);
}
}
}
}
public void removeImage(DragImage img) {
images.remove(img);
repaint();
}
protected void setDragImages(DragImages dragImages) {
this.dropImages = dragImages;
repaint();
}
public void addImagesAt(Point location, List images) {
if (images != null && images.size() > 0) {
for (Object obj : images) {
if (obj instanceof Image) {
Image img = (Image) obj;
addImageAt(location, img);
location.x += 10;
location.y += 10;
if (location.x >= getWidth()) {
location.x = 0;
}
if (location.y >= getHeight()) {
location.y = 0;
}
}
}
}
}
protected void addImages(DragImages dragImages) {
for (DragImage di : dragImages.getImages()) {
images.add(di);
}
repaint();
}
protected void addImagesAt(Point dropPoint, DragImages dragImages) {
Point offset = dragImages.getOffset();
for (DragImage di : dragImages.getImages()) {
Point p = di.getLocation();
p.x = dropPoint.x - offset.x;
p.y = dropPoint.y - offset.y;
images.add(di);
}
repaint();
}
protected void setDragPoint(Point location) {
dragPoint = location;
repaint();
}
}
public static class ImageTransferable implements Transferable {
public static final DataFlavor DRAG_IMAGE_DATA_FLAVOR = new DataFlavor(List.class, "Images");
private DragImages dragImages;
public ImageTransferable(DragImages dragImages) {
this.dragImages = dragImages;
}
@Override
public DataFlavor[] getTransferDataFlavors() {
return new DataFlavor[]{DRAG_IMAGE_DATA_FLAVOR};
}
@Override
public boolean isDataFlavorSupported(DataFlavor flavor) {
return DRAG_IMAGE_DATA_FLAVOR.equals(flavor);
}
@Override
public Object getTransferData(DataFlavor flavor) throws UnsupportedFlavorException, IOException {
return dragImages;
}
}
public class DragImage {
private Image image;
private Point p;
public DragImage(Image image, Point p) {
this.image = image;
this.p = p;
}
public Image getImage() {
return image;
}
public Point getLocation() {
return p;
}
public Dimension getSize() {
return new Dimension(image.getWidth(null), image.getHeight(null));
}
public boolean contains(Point p) {
return new Rectangle(getLocation(), getSize()).contains(p);
}
}
public class DragImages {
private Point offset;
private List<DragImage> images;
public DragImages(Point offset, DragImage... images) {
this.offset = offset;
this.images = Arrays.asList(images);
}
public Point getOffset() {
return offset;
}
public List<DragImage> getImages() {
return images;
}
}
protected class DragGestureHandler implements DragGestureListener {
private ImagePane imagePane;
public DragGestureHandler(ImagePane list) {
this.imagePane = list;
}
@Override
public void dragGestureRecognized(DragGestureEvent dge) {
DragImage di = imagePane.getImageAt(dge.getDragOrigin());
if (di != null) {
Point origin = dge.getDragOrigin();
Point p = new Point();
p.x = origin.x - di.getLocation().x;
p.y = origin.y - di.getLocation().y;
Transferable t = new ImageTransferable(new DragImages(p, di));
imagePane.removeImage(di);
DragSource ds = dge.getDragSource();
ds.startDrag(
dge,
null,
t,
new DragSourceHandler(imagePane));
}
}
}
protected class DragSourceHandler implements DragSourceListener {
private ImagePane pane;
public DragSourceHandler(ImagePane pane) {
this.pane = pane;
}
public void dragEnter(DragSourceDragEvent dsde) {
}
public void dragOver(DragSourceDragEvent dsde) {
pane.repaint();
}
public void dropActionChanged(DragSourceDragEvent dsde) {
}
public void dragExit(DragSourceEvent dse) {
}
public void dragDropEnd(DragSourceDropEvent dsde) {
if (!dsde.getDropSuccess()) {
Transferable t = dsde.getDragSourceContext().getTransferable();
if (t != null) {
try {
Object transferData = t.getTransferData(ImageTransferable.DRAG_IMAGE_DATA_FLAVOR);
if (transferData instanceof DragImages) {
DragImages di = (DragImages) transferData;
pane.addImages(di);
}
} catch (UnsupportedFlavorException | IOException ex) {
ex.printStackTrace();
}
}
}
}
}
protected class DropTargetHandler implements DropTargetListener {
private ImagePane panel;
public DropTargetHandler(ImagePane panel) {
this.panel = panel;
}
public void dragEnter(DropTargetDragEvent dtde) {
if (dtde.getTransferable().isDataFlavorSupported(ImageTransferable.DRAG_IMAGE_DATA_FLAVOR)) {
dtde.acceptDrag(DnDConstants.ACTION_COPY_OR_MOVE);
updateDragImages(dtde);
} else {
dtde.rejectDrag();
}
}
public void dragOver(DropTargetDragEvent dtde) {
updateDragImages(dtde);
panel.repaint();
}
public void dropActionChanged(DropTargetDragEvent dtde) {
}
public void dragExit(DropTargetEvent dte) {
panel.setDragImages(null);
}
public void drop(DropTargetDropEvent dtde) {
panel.setDragImages(null);
if (dtde.getTransferable().isDataFlavorSupported(ImageTransferable.DRAG_IMAGE_DATA_FLAVOR)) {
Transferable t = dtde.getTransferable();
if (t.isDataFlavorSupported(ImageTransferable.DRAG_IMAGE_DATA_FLAVOR)) {
try {
Object transferData = t.getTransferData(ImageTransferable.DRAG_IMAGE_DATA_FLAVOR);
if (transferData instanceof DragImages) {
DragImages images = (DragImages) transferData;
dtde.dropComplete(true);
dtde.acceptDrop(DnDConstants.ACTION_COPY_OR_MOVE);
panel.addImagesAt(dtde.getLocation(), images);
} else {
dtde.rejectDrop();
}
} catch (UnsupportedFlavorException ex) {
ex.printStackTrace();
dtde.rejectDrop();
} catch (IOException ex) {
ex.printStackTrace();
dtde.rejectDrop();
}
} else {
dtde.rejectDrop();
}
}
}
protected void updateDragImages(DropTargetDragEvent dtde) {
panel.setDragImages(null);
Transferable t = dtde.getTransferable();
if (t != null) {
try {
Object transferData = t.getTransferData(ImageTransferable.DRAG_IMAGE_DATA_FLAVOR);
if (transferData instanceof DragImages) {
panel.setDragPoint(dtde.getLocation());
panel.setDragImages((DragImages)transferData);
}
} catch (UnsupportedFlavorException | IOException ex) {
ex.printStackTrace();
}
}
}
}
}
这篇关于拖放后移动组件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！
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