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    <p>Drag and Drop can be a complex beast, not made any easier by the conflicting information that's available. Personally, I like to avoid the Transfer API, but I'm old school like that.</p> <p>The glue to DnD really is the <code>DataFlavor</code>. I prefer to roll my own, makes life a lot easier.</p> <p>In this example, I've used a single <code>TransferHandler</code>, but realistically, you really should have one for dragging and one for dropping, in particular, you should have one for each component you want to drop onto.</p> <p>The main reason for this is, I put a trap in my <code>canImport</code> method to reject it if your dragging over a <code>JList</code>, so you can only drop it on the <code>JLabel</code>, this is a little hack and probably not the best idea.</p> <pre><code>import java.awt.BorderLayout; import java.awt.Component; import java.awt.EventQueue; import java.awt.GridBagConstraints; 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.io.IOException; import javax.swing.DefaultListModel; import javax.swing.JComponent; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JList; import javax.swing.JPanel; import javax.swing.JScrollPane; import javax.swing.TransferHandler; import javax.swing.UIManager; import javax.swing.UnsupportedLookAndFeelException; public class DnDTransferableTest { public static void main(String[] args) { new DnDTransferableTest(); } public DnDTransferableTest() { EventQueue.invokeLater(new Runnable() { @Override public void run() { try { UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName()); } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) { } JFrame frame = new JFrame("Testing"); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.setLayout(new BorderLayout()); frame.add(new TestPane()); frame.pack(); frame.setLocationRelativeTo(null); frame.setVisible(true); } }); } @SuppressWarnings("serial") public class TestPane extends JPanel { private JList&lt;ListItem&gt; list; private JLabel label; public TestPane() { list = new JList&lt;ListItem&gt;(); list.setDragEnabled(true); list.setTransferHandler(new ListTransferHandler()); DefaultListModel&lt;ListItem&gt; model = new DefaultListModel&lt;ListItem&gt;(); for (int index = 0; index &lt; 10; index++) { model.addElement(new ListItem("Item " + index)); } list.setModel(model); setLayout(new GridBagLayout()); GridBagConstraints gbc = new GridBagConstraints(); gbc.gridx = 0; gbc.gridy = 0; gbc.weighty = 1; gbc.weightx = 1; gbc.fill = GridBagConstraints.BOTH; add(new JScrollPane(list), gbc); label = new JLabel("Drag on me..."); gbc.gridx++; gbc.weightx = 1; gbc.fill = GridBagConstraints.NONE; add(label, gbc); label.setTransferHandler(new ListTransferHandler()); } } @SuppressWarnings("serial") public class ListTransferHandler extends TransferHandler { @Override public boolean canImport(TransferSupport support) { return (support.getComponent() instanceof JLabel) &amp;&amp; support.isDataFlavorSupported(ListItemTransferable.LIST_ITEM_DATA_FLAVOR); } @Override public boolean importData(TransferSupport support) { boolean accept = false; if (canImport(support)) { try { Transferable t = support.getTransferable(); Object value = t.getTransferData(ListItemTransferable.LIST_ITEM_DATA_FLAVOR); if (value instanceof ListItem) { Component component = support.getComponent(); if (component instanceof JLabel) { ((JLabel)component).setText(((ListItem)value).getText()); accept = true; } } } catch (Exception exp) { exp.printStackTrace(); } } return accept; } @Override public int getSourceActions(JComponent c) { return DnDConstants.ACTION_COPY_OR_MOVE; } @Override protected Transferable createTransferable(JComponent c) { Transferable t = null; if (c instanceof JList) { @SuppressWarnings("unchecked") JList&lt;ListItem&gt; list = (JList&lt;ListItem&gt;) c; Object value = list.getSelectedValue(); if (value instanceof ListItem) { ListItem li = (ListItem) value; t = new ListItemTransferable(li); } } return t; } @Override protected void exportDone(JComponent source, Transferable data, int action) { System.out.println("ExportDone"); // Here you need to decide how to handle the completion of the transfer, // should you remove the item from the list or not... } } public static class ListItemTransferable implements Transferable { public static final DataFlavor LIST_ITEM_DATA_FLAVOR = new DataFlavor(ListItem.class, "java/ListItem"); private ListItem listItem; public ListItemTransferable(ListItem listItem) { this.listItem = listItem; } @Override public DataFlavor[] getTransferDataFlavors() { return new DataFlavor[]{LIST_ITEM_DATA_FLAVOR}; } @Override public boolean isDataFlavorSupported(DataFlavor flavor) { return flavor.equals(LIST_ITEM_DATA_FLAVOR); } @Override public Object getTransferData(DataFlavor flavor) throws UnsupportedFlavorException, IOException { return listItem; } } public static class ListItem { private String text; public ListItem(String text) { this.text = text; } public String getText() { return text; } @Override public String toString() { return getText(); } } } </code></pre>
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    1. COThis is exactly what I was looking for, explained perfectly! Thanks!
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    2. CODo you mean single `Transferable` or single `TransferHandler`?
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    3. CO@johnchen902 Who knows what I mean, I think your right, it sounds like TransferHandler
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