也許就是這樣。我在handlerLabel中添加了內部類MyLabel和控制檯輸出。在您的main下按Ctrl + v。它將打印以控制每個MyLabels的originalString屬性。
public class MyLabel extends JLabel {
String original;
public MyLabel (String text)
{
super(text);
this.original=text;
}
public String getOriginal() {
return original;
}
public void setOriginal(String original) {
this.original = original;
}
}
public deneme2() {
JPanel panel= new JPanel();
MouseListener listener = (MouseListener) new DragMouseAdapter();
MyLabel label1 = new MyLabel("Label1111111");
handlerLabel(label1);
label1.addMouseListener(listener);
panel.add(label1);
MyLabel label2 = new MyLabel("Label2222222");
handlerLabel(label2);
label2.addMouseListener(listener);
panel.add(label2);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setBounds(100, 100, 450, 300);
contentPane = new JPanel();
contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
contentPane.setLayout(new BorderLayout(0, 0));
contentPane.add(panel);
setContentPane(contentPane);
}
private void handlerLabel(MyLabel lbl) {
lbl.setTransferHandler(new TransferHandler("text") {
@Override
protected void exportDone(JComponent source, Transferable data, int action) {
if (action == COPY) {
System.out.println(((MyLabel) lbl.getDropTarget().getDropTargetContext().getComponent()).getOriginal());
}
}
});
}
編輯：檢查了這一點。在你的主目錄下按Ctrl + V。它將打印到源標籤的文本和目標標籤的文本，也是original屬性。 MyLabel類執行DropTargetListener，然後由new DropTarget(this, this)註冊。然後我們定義覆蓋drop方法會發生什麼。
public class MyLabel extends JLabel implements DropTargetListener {
String original;
public MyLabel(String text) {
super(text);
this.original = text;
new DropTarget(this, this);
this.setTransferHandler(new TransferHandler("text"));
final MouseListener listener = new MouseAdapter() {
@Override
public void mousePressed(final MouseEvent me) {
final MyLabel label = (MyLabel) me.getSource();
final TransferHandler handler = label.getTransferHandler();
handler.exportAsDrag(label, me, TransferHandler.COPY);
}
};
this.addMouseListener(listener);
}
public String getOriginal() {
return original;
}
public void setOriginal(String original) {
this.original = original;
}
@Override
public void dragEnter(DropTargetDragEvent dtde) {
}
@Override
public void dragOver(DropTargetDragEvent dtde) {
}
@Override
public void dropActionChanged(DropTargetDragEvent dtde) {
}
@Override
public void dragExit(DropTargetEvent dte) {
}
@Override
public void drop(DropTargetDropEvent dtde) {
try {
final String sourceString = (String) dtde.getTransferable().getTransferData(new DataFlavor("application/x-java-jvm-local-objectref; class=java.lang.String"));
System.out.println("Source: " + sourceString + " target: " + this.getText());
this.setText(sourceString);
System.out.println("Original target: "+this.getOriginal());
} catch (final UnsupportedFlavorException | IOException | ClassNotFoundException e) {
e.printStackTrace();
}
}
}
public deneme2() {
JPanel panel = new JPanel();
MyLabel label1 = new MyLabel("Label1111111a");
panel.add(label1);
MyLabel label2 = new MyLabel("Label2222222b");
panel.add(label2);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setBounds(100, 100, 450, 300);
contentPane = new JPanel();
contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
contentPane.setLayout(new BorderLayout(0, 0));
contentPane.add(panel);
setContentPane(contentPane);
}
}
EDIT2：下面的代碼生成
這樣的結果
看到這個答案的最終結果是：
或
它還打印original財產安慰。這些可以有不同的組織方式（MyLabel,MyLabelTransferable,MyLabelDropTargetListener,MyLabelTransferHandler類，只是爲了給未來的重構一個想法），但它也以這種方式工作。考慮一下你的用例的quickfix。
所以主類是這樣的：
public class Deneme2 extends JFrame {
private static final int COPY = 0;
private static final int NONE = 0;
public static void main(String[] args) {
Deneme2 mainFrame = new Deneme2();
SwingUtilities.invokeLater(() -> {//let's get that frame on EDT rollin lambda style:)
mainFrame.setVisible(true);
});
}
public Deneme2() {
JPanel panel = new JPanel();
panel.setLayout(new BorderLayout());
MyLabel label1 = new MyLabel("Label1111111a");
panel.add(label1, BorderLayout.WEST);
MyLabel label2 = new MyLabel("Label2222222b");
panel.add(label2, BorderLayout.EAST);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setBounds(100, 100, 450, 300);
panel.setBorder(new EmptyBorder(5, 5, 5, 5));
this.add(panel);
}
}
然後MyLabel.java：
public class MyLabel extends JLabel implements DropTargetListener, Transferable {
String original;
protected static final DataFlavor MYLABEL_DATA_FLAVOR = new DataFlavor(DataFlavor.javaJVMLocalObjectMimeType + "; class=\"" + MyLabel.class.getCanonicalName() + "\"",
"MyLabel label");
protected static final DataFlavor[] SUPPORTED_FLAVORS = {MYLABEL_DATA_FLAVOR};
public MyLabel(String text) {
super(text);
this.original = text;
new DropTarget(this, this);
this.setTransferHandler(new MyLabelTransferHandler()); //here we use our custom TransferHandler
final MouseListener listener = new MouseAdapter() {
@Override
public void mousePressed(final MouseEvent me) {
final MyLabel label = (MyLabel) me.getSource();
final TransferHandler handler = label.getTransferHandler();
handler.exportAsDrag(label, me, TransferHandler.COPY);
}
};
this.addMouseListener(listener);
}
public String getOriginal() {
return original;
}
public void setOriginal(String original) {
this.original = original;
}
@Override
public void dragEnter(DropTargetDragEvent dtde) {
if (dtde.getTransferable().isDataFlavorSupported(MyLabel.MYLABEL_DATA_FLAVOR)) {
System.out.println("Drop accept - MyLabel");
dtde.acceptDrag(DnDConstants.ACTION_COPY_OR_MOVE);
} else {
dtde.rejectDrag();
}
}
@Override
public void dragOver(DropTargetDragEvent dtde) {
//System.out.println("Drag over");
}
@Override
public void dropActionChanged(DropTargetDragEvent dtde) {
System.out.println("Action changed");
}
@Override
public void dragExit(DropTargetEvent dte) {
System.out.println("Exited");
}
@Override
public void drop(DropTargetDropEvent dtde) {
System.out.println("Drop detected");
if (dtde.getTransferable().isDataFlavorSupported(MyLabel.MYLABEL_DATA_FLAVOR)) {
Transferable t = dtde.getTransferable();
if (t.isDataFlavorSupported(MyLabel.MYLABEL_DATA_FLAVOR)) {
try {
Object transferData = t.getTransferData(MyLabel.MYLABEL_DATA_FLAVOR);
if (transferData instanceof MyLabel) {
MyLabel mySourceLabel = (MyLabel) transferData;
if (!(mySourceLabel.equals(this))) {
dtde.acceptDrop(DnDConstants.ACTION_COPY_OR_MOVE);
this.setText(mySourceLabel.getText());
mySourceLabel.setText("Empty");
System.out.println(mySourceLabel.getOriginal() + " " + this.getOriginal());
} else {
dtde.rejectDrop();
System.out.println("Drop rejected - the same MyLabel");
}
} else {
dtde.rejectDrop();
}
} catch (UnsupportedFlavorException | IOException ex) {
dtde.rejectDrop();
}
} else {
dtde.rejectDrop();
}
}
}
@Override
public DataFlavor[] getTransferDataFlavors() {
return SUPPORTED_FLAVORS;
}
@Override
public boolean isDataFlavorSupported(DataFlavor flavor) {
return flavor.equals(MYLABEL_DATA_FLAVOR) || flavor.equals(DataFlavor.stringFlavor);
}
@Override
public Object getTransferData(DataFlavor flavor) throws UnsupportedFlavorException, IOException {
if (flavor.equals(MYLABEL_DATA_FLAVOR)) {
return this;
} else if (flavor.equals(DataFlavor.stringFlavor)) {
return this.getText();
} else {
throw new UnsupportedFlavorException(flavor);
}
}
}
然後MyLabelTransferHandler.java：
public class MyLabelTransferHandler extends TransferHandler {
@Override
public boolean canImport(TransferHandler.TransferSupport support) {
return (support.getComponent() instanceof MyLabel) && support.isDataFlavorSupported(MyLabel.MYLABEL_DATA_FLAVOR);
}
@Override
public boolean importData(JComponent src, Transferable transferable) {
return src instanceof MyLabel;
}
@Override
public int getSourceActions(JComponent c) {
return DnDConstants.ACTION_COPY;
}
@Override
protected Transferable createTransferable(JComponent c) {
Transferable t = (MyLabel)c;
return t;
}
@Override
protected void exportDone(JComponent source, Transferable data, int action) {
System.out.println("Export done.");
}
}
後最終編輯結果如下：
澄清一下：
protected static final DataFlavor MYLABEL_DATA_FLAVOR = new DataFlavor(DataFlavor.javaJVMLocalObjectMimeType + "; class=\"" + MyLabel.class.getCanonicalName() + "\"",
"MyLabel label");
在MyLabel
。這是重要的路線。這將使getTransferData()返回相同的實例MyLabel。如果你會做這樣的：
protected static final DataFlavor MYLABEL_DATA_FLAVOR = new DataFlavor(MyLabel.class, "MyLabel label");
您將無法，改變重寫drop()方法mySourceLabel文本爲「空」，因爲你會被給予該對象的副本。
還Why shouldn't you extend JFrame and other components?。並且您可以提供對「空白」文本的檢查（如果getText()返回「空白」，則不要更改目標MyLabel中的文本）。
如果這有幫助，接受答案:)
謝謝你的回答。但是當我拖動Label11111時，我需要在Label22222中獲取值並檢查它。我無法以這種方式獲得Label22222。如果你能幫助解決這個問題，我將不勝感激。 – MeHcKeR
所以當我拖動Label1111時，我需要在Label2222中獲取Text（）來檢查它。 – MeHcKeR
@MeHcKeR編輯了我的答案。 – bigby