Mega Code Archive
Drag List Demo
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/* From http://java.sun.com/docs/books/tutorial/index.html */
/*
* Copyright (c) 2006 Sun Microsystems, Inc. All Rights Reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* -Redistribution of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* -Redistribution in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* Neither the name of Sun Microsystems, Inc. or the names of contributors may
* be used to endorse or promote products derived from this software without
* specific prior written permission.
*
* This software is provided "AS IS," without a warranty of any kind. ALL
* EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING
* ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE
* OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN MIDROSYSTEMS, INC. ("SUN")
* AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE
* AS A RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS
* DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR ANY LOST
* REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL,
* INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY
* OF LIABILITY, ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE,
* EVEN IF SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
*
* You acknowledge that this software is not designed, licensed or intended
* for use in the design, construction, operation or maintenance of any
* nuclear facility.
*/
/*
* DragListDemo.java is a 1.4 example that requires the following file:
* ArrayListTransferHandler.java
*/
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.datatransfer.DataFlavor;
import java.awt.datatransfer.Transferable;
import java.awt.datatransfer.UnsupportedFlavorException;
import java.io.IOException;
import java.util.ArrayList;
import javax.swing.BorderFactory;
import javax.swing.DefaultListModel;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JList;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.ListSelectionModel;
import javax.swing.TransferHandler;
public class DragListDemo extends JPanel {
ArrayListTransferHandler arrayListHandler;
public DragListDemo() {
arrayListHandler = new ArrayListTransferHandler();
JList list1, list2;
DefaultListModel list1Model = new DefaultListModel();
list1Model.addElement("0 (list 1)");
list1Model.addElement("1 (list 1)");
list1Model.addElement("2 (list 1)");
list1Model.addElement("3 (list 1)");
list1Model.addElement("4 (list 1)");
list1Model.addElement("5 (list 1)");
list1Model.addElement("6 (list 1)");
list1 = new JList(list1Model);
list1.setSelectionMode(ListSelectionModel.SINGLE_INTERVAL_SELECTION);
list1.setTransferHandler(arrayListHandler);
list1.setDragEnabled(true);
JScrollPane list1View = new JScrollPane(list1);
list1View.setPreferredSize(new Dimension(200, 100));
JPanel panel1 = new JPanel();
panel1.setLayout(new BorderLayout());
panel1.add(list1View, BorderLayout.CENTER);
panel1.setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));
DefaultListModel list2Model = new DefaultListModel();
list2Model.addElement("0 (list 2)");
list2Model.addElement("1 (list 2)");
list2Model.addElement("2 (list 2)");
list2Model.addElement("3 (list 2)");
list2Model.addElement("4 (list 2)");
list2Model.addElement("5 (list 2)");
list2Model.addElement("6 (list 2)");
list2 = new JList(list2Model);
list2.setSelectionMode(ListSelectionModel.SINGLE_INTERVAL_SELECTION);
list2.setTransferHandler(arrayListHandler);
list2.setDragEnabled(true);
JScrollPane list2View = new JScrollPane(list2);
list2View.setPreferredSize(new Dimension(200, 100));
JPanel panel2 = new JPanel();
panel2.setLayout(new BorderLayout());
panel2.add(list2View, BorderLayout.CENTER);
panel2.setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));
setLayout(new BorderLayout());
add(panel1, BorderLayout.LINE_START);
add(panel2, BorderLayout.LINE_END);
setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));
}
/**
* Create the GUI and show it. For thread safety, this method should be
* invoked from the event-dispatching thread.
*/
private static void createAndShowGUI() {
//Make sure we have nice window decorations.
JFrame.setDefaultLookAndFeelDecorated(true);
//Create and set up the window.
JFrame frame = new JFrame("DragListDemo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//Create and set up the content pane.
DragListDemo demo = new DragListDemo();
frame.setContentPane(demo);
//Display the window.
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
//Schedule a job for the event-dispatching thread:
//creating and showing this application's GUI.
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
}
/*
* ArrayListTransferHandler.java is used by the 1.4 DragListDemo.java example.
*/
class ArrayListTransferHandler extends TransferHandler {
DataFlavor localArrayListFlavor, serialArrayListFlavor;
String localArrayListType = DataFlavor.javaJVMLocalObjectMimeType
+ ";class=java.util.ArrayList";
JList source = null;
int[] indices = null;
int addIndex = -1; //Location where items were added
int addCount = 0; //Number of items added
public ArrayListTransferHandler() {
try {
localArrayListFlavor = new DataFlavor(localArrayListType);
} catch (ClassNotFoundException e) {
System.out
.println("ArrayListTransferHandler: unable to create data flavor");
}
serialArrayListFlavor = new DataFlavor(ArrayList.class, "ArrayList");
}
public boolean importData(JComponent c, Transferable t) {
JList target = null;
ArrayList alist = null;
if (!canImport(c, t.getTransferDataFlavors())) {
return false;
}
try {
target = (JList) c;
if (hasLocalArrayListFlavor(t.getTransferDataFlavors())) {
alist = (ArrayList) t.getTransferData(localArrayListFlavor);
} else if (hasSerialArrayListFlavor(t.getTransferDataFlavors())) {
alist = (ArrayList) t.getTransferData(serialArrayListFlavor);
} else {
return false;
}
} catch (UnsupportedFlavorException ufe) {
System.out.println("importData: unsupported data flavor");
return false;
} catch (IOException ioe) {
System.out.println("importData: I/O exception");
return false;
}
//At this point we use the same code to retrieve the data
//locally or serially.
//We'll drop at the current selected index.
int index = target.getSelectedIndex();
//Prevent the user from dropping data back on itself.
//For example, if the user is moving items #4,#5,#6 and #7 and
//attempts to insert the items after item #5, this would
//be problematic when removing the original items.
//This is interpreted as dropping the same data on itself
//and has no effect.
if (source.equals(target)) {
if (indices != null && index >= indices[0] - 1
&& index <= indices[indices.length - 1]) {
indices = null;
return true;
}
}
DefaultListModel listModel = (DefaultListModel) target.getModel();
int max = listModel.getSize();
if (index < 0) {
index = max;
} else {
index++;
if (index > max) {
index = max;
}
}
addIndex = index;
addCount = alist.size();
for (int i = 0; i < alist.size(); i++) {
listModel.add(index++, alist.get(i));
}
return true;
}
protected void exportDone(JComponent c, Transferable data, int action) {
if ((action == MOVE) && (indices != null)) {
DefaultListModel model = (DefaultListModel) source.getModel();
//If we are moving items around in the same list, we
//need to adjust the indices accordingly since those
//after the insertion point have moved.
if (addCount > 0) {
for (int i = 0; i < indices.length; i++) {
if (indices[i] > addIndex) {
indices[i] += addCount;
}
}
}
for (int i = indices.length - 1; i >= 0; i--)
model.remove(indices[i]);
}
indices = null;
addIndex = -1;
addCount = 0;
}
private boolean hasLocalArrayListFlavor(DataFlavor[] flavors) {
if (localArrayListFlavor == null) {
return false;
}
for (int i = 0; i < flavors.length; i++) {
if (flavors[i].equals(localArrayListFlavor)) {
return true;
}
}
return false;
}
private boolean hasSerialArrayListFlavor(DataFlavor[] flavors) {
if (serialArrayListFlavor == null) {
return false;
}
for (int i = 0; i < flavors.length; i++) {
if (flavors[i].equals(serialArrayListFlavor)) {
return true;
}
}
return false;
}
public boolean canImport(JComponent c, DataFlavor[] flavors) {
if (hasLocalArrayListFlavor(flavors)) {
return true;
}
if (hasSerialArrayListFlavor(flavors)) {
return true;
}
return false;
}
protected Transferable createTransferable(JComponent c) {
if (c instanceof JList) {
source = (JList) c;
indices = source.getSelectedIndices();
Object[] values = source.getSelectedValues();
if (values == null || values.length == 0) {
return null;
}
ArrayList alist = new ArrayList(values.length);
for (int i = 0; i < values.length; i++) {
Object o = values[i];
String str = o.toString();
if (str == null)
str = "";
alist.add(str);
}
return new ArrayListTransferable(alist);
}
return null;
}
public int getSourceActions(JComponent c) {
return COPY_OR_MOVE;
}
public class ArrayListTransferable implements Transferable {
ArrayList data;
public ArrayListTransferable(ArrayList alist) {
data = alist;
}
public Object getTransferData(DataFlavor flavor)
throws UnsupportedFlavorException {
if (!isDataFlavorSupported(flavor)) {
throw new UnsupportedFlavorException(flavor);
}
return data;
}
public DataFlavor[] getTransferDataFlavors() {
return new DataFlavor[] { localArrayListFlavor,
serialArrayListFlavor };
}
public boolean isDataFlavorSupported(DataFlavor flavor) {
if (localArrayListFlavor.equals(flavor)) {
return true;
}
if (serialArrayListFlavor.equals(flavor)) {
return true;
}
return false;
}
}
}
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