Java tutorial
/* * Copyright (c) 1995, 2008, Oracle and/or its affiliates. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * - Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * - Redistributions 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 Oracle or the names of its * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ package dnd; import javax.swing.*; import javax.swing.tree.*; import javax.swing.event.*; import java.awt.*; import java.awt.datatransfer.*; import java.awt.event.*; import java.io.*; public class LocationSensitiveDemo extends JFrame { private DefaultListModel model = new DefaultListModel(); private int count = 0; private JTree tree; private JComboBox indicateCombo; private DefaultTreeModel treeModel; private TreePath namesPath; private static DefaultTreeModel getDefaultTreeModel() { DefaultMutableTreeNode root = new DefaultMutableTreeNode("things"); DefaultMutableTreeNode parent; DefaultMutableTreeNode nparent; parent = new DefaultMutableTreeNode("colors"); root.add(parent); parent.add(new DefaultMutableTreeNode("red")); parent.add(new DefaultMutableTreeNode("yellow")); parent.add(new DefaultMutableTreeNode("green")); parent.add(new DefaultMutableTreeNode("blue")); parent.add(new DefaultMutableTreeNode("purple")); parent = new DefaultMutableTreeNode("names"); root.add(parent); nparent = new DefaultMutableTreeNode("men"); nparent.add(new DefaultMutableTreeNode("jack")); nparent.add(new DefaultMutableTreeNode("kieran")); nparent.add(new DefaultMutableTreeNode("william")); nparent.add(new DefaultMutableTreeNode("jose")); parent.add(nparent); nparent = new DefaultMutableTreeNode("women"); nparent.add(new DefaultMutableTreeNode("jennifer")); nparent.add(new DefaultMutableTreeNode("holly")); nparent.add(new DefaultMutableTreeNode("danielle")); nparent.add(new DefaultMutableTreeNode("tara")); parent.add(nparent); parent = new DefaultMutableTreeNode("sports"); root.add(parent); parent.add(new DefaultMutableTreeNode("basketball")); parent.add(new DefaultMutableTreeNode("soccer")); parent.add(new DefaultMutableTreeNode("football")); nparent = new DefaultMutableTreeNode("hockey"); parent.add(nparent); nparent.add(new DefaultMutableTreeNode("ice hockey")); nparent.add(new DefaultMutableTreeNode("roller hockey")); nparent.add(new DefaultMutableTreeNode("floor hockey")); nparent.add(new DefaultMutableTreeNode("road hockey")); parent = new DefaultMutableTreeNode("food"); root.add(parent); parent.add(new DefaultMutableTreeNode("pizza")); parent.add(new DefaultMutableTreeNode("wings")); parent.add(new DefaultMutableTreeNode("pasta")); nparent = new DefaultMutableTreeNode("fruit"); parent.add(nparent); nparent.add(new DefaultMutableTreeNode("bananas")); nparent.add(new DefaultMutableTreeNode("apples")); nparent.add(new DefaultMutableTreeNode("grapes")); nparent.add(new DefaultMutableTreeNode("pears")); return new DefaultTreeModel(root); } public LocationSensitiveDemo() { super("Location Sensitive Drag and Drop Demo"); treeModel = getDefaultTreeModel(); tree = new JTree(treeModel); tree.setBorder(BorderFactory.createEmptyBorder(2, 4, 2, 4)); tree.getSelectionModel().setSelectionMode(TreeSelectionModel.DISCONTIGUOUS_TREE_SELECTION); tree.setDropMode(DropMode.ON); namesPath = tree.getPathForRow(2); tree.expandRow(2); tree.expandRow(1); tree.setRowHeight(0); tree.setTransferHandler(new TransferHandler() { public boolean canImport(TransferHandler.TransferSupport info) { // for the demo, we'll only support drops (not clipboard paste) if (!info.isDrop()) { return false; } String item = (String) indicateCombo.getSelectedItem(); if (item.equals("Always")) { info.setShowDropLocation(true); } else if (item.equals("Never")) { info.setShowDropLocation(false); } // we only import Strings if (!info.isDataFlavorSupported(DataFlavor.stringFlavor)) { return false; } // fetch the drop location JTree.DropLocation dl = (JTree.DropLocation) info.getDropLocation(); TreePath path = dl.getPath(); // we don't support invalid paths or descendants of the names folder if (path == null || namesPath.isDescendant(path)) { return false; } return true; } public boolean importData(TransferHandler.TransferSupport info) { // if we can't handle the import, say so if (!canImport(info)) { return false; } // fetch the drop location JTree.DropLocation dl = (JTree.DropLocation) info.getDropLocation(); // fetch the path and child index from the drop location TreePath path = dl.getPath(); int childIndex = dl.getChildIndex(); // fetch the data and bail if this fails String data; try { data = (String) info.getTransferable().getTransferData(DataFlavor.stringFlavor); } catch (UnsupportedFlavorException e) { return false; } catch (IOException e) { return false; } // if child index is -1, the drop was on top of the path, so we'll // treat it as inserting at the end of that path's list of children if (childIndex == -1) { childIndex = tree.getModel().getChildCount(path.getLastPathComponent()); } // create a new node to represent the data and insert it into the model DefaultMutableTreeNode newNode = new DefaultMutableTreeNode(data); DefaultMutableTreeNode parentNode = (DefaultMutableTreeNode) path.getLastPathComponent(); treeModel.insertNodeInto(newNode, parentNode, childIndex); // make the new node visible and scroll so that it's visible tree.makeVisible(path.pathByAddingChild(newNode)); tree.scrollRectToVisible(tree.getPathBounds(path.pathByAddingChild(newNode))); // demo stuff - remove for blog model.removeAllElements(); model.insertElementAt("String " + (++count), 0); // end demo stuff return true; } }); JList dragFrom = new JList(model); dragFrom.setFocusable(false); dragFrom.setPrototypeCellValue("String 0123456789"); model.insertElementAt("String " + count, 0); dragFrom.setDragEnabled(true); dragFrom.setBorder(BorderFactory.createLoweredBevelBorder()); JPanel p = new JPanel(); p.setLayout(new BoxLayout(p, BoxLayout.X_AXIS)); JPanel wrap = new JPanel(); wrap.add(new JLabel("Drag from here:")); wrap.add(dragFrom); p.add(Box.createHorizontalStrut(4)); p.add(Box.createGlue()); p.add(wrap); p.add(Box.createGlue()); p.add(Box.createHorizontalStrut(4)); getContentPane().add(p, BorderLayout.NORTH); getContentPane().add(new JScrollPane(tree), BorderLayout.CENTER); indicateCombo = new JComboBox(new String[] { "Default", "Always", "Never" }); indicateCombo.setSelectedItem("INSERT"); p = new JPanel(); p.setLayout(new BoxLayout(p, BoxLayout.X_AXIS)); wrap = new JPanel(); wrap.add(new JLabel("Show drop location:")); wrap.add(indicateCombo); p.add(Box.createHorizontalStrut(4)); p.add(Box.createGlue()); p.add(wrap); p.add(Box.createGlue()); p.add(Box.createHorizontalStrut(4)); getContentPane().add(p, BorderLayout.SOUTH); getContentPane().setPreferredSize(new Dimension(400, 450)); } private static void increaseFont(String type) { Font font = UIManager.getFont(type); font = font.deriveFont(font.getSize() + 4f); UIManager.put(type, font); } private static void createAndShowGUI() { //Create and set up the window. LocationSensitiveDemo test = new LocationSensitiveDemo(); test.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); //Display the window. test.pack(); test.setVisible(true); } public static void main(String[] args) { SwingUtilities.invokeLater(new Runnable() { public void run() { try { UIManager.setLookAndFeel("com.sun.java.swing.plaf.windows.WindowsLookAndFeel"); increaseFont("Tree.font"); increaseFont("Label.font"); increaseFont("ComboBox.font"); increaseFont("List.font"); } catch (Exception e) { } //Turn off metal's use of bold fonts UIManager.put("swing.boldMetal", Boolean.FALSE); createAndShowGUI(); } }); } }