TestD&DTree_e.rar

/* * Created on 2005-4-14 * * TODO To change the template for this generated file go to * Window - Preferences - Java - Code Style - Code Templates */ /** * @author fangkun * Third class : AbstractTreeTransferHandler * This class is the most important. It manages all the DnD behavior. * It is abstract because it contains two abstract methods : * public abstract boolean canPerformAction(DNDTree target, MyDiskInfoTree draggedNode, int action, Point location); * and : * public abstract boolean executeDrop(DNDTree tree, MyDiskInfoTree draggedNode, MyDiskInfoTree newParentNode, int action); * * we have to override to give the required behavior of DnD in your tree. * * TODO To change the template for this generated type comment go to * Window - Preferences - Java - Code Style - Code Templates */ import java.awt.*; import javax.swing.*; import javax.swing.tree.*; import java.awt.dnd.*; import java.awt.datatransfer.*; import java.awt.image.*; public abstract class AbstractTreeTransferHandler implements DragGestureListener, DragSourceListener, DropTargetListener { private DNDTree tree; private DragSource dragSource; // dragsource private DropTarget dropTarget; //droptarget private static MyDiskInfoTree draggedNode; private MyDiskInfoTree draggedNodeParent; private static BufferedImage image = null; //buff image private Rectangle rect2D = new Rectangle(); private boolean drawImage; protected AbstractTreeTransferHandler(DNDTree tree, int action, boolean drawIcon) { this.tree = tree; drawImage = drawIcon; dragSource = new DragSource(); dragSource.createDefaultDragGestureRecognizer(tree, action, this); dropTarget = new DropTarget(tree, action, this); } /* Methods for DragSourceListener */ public void dragDropEnd(DragSourceDropEvent dsde) { if (dsde.getDropSuccess() && dsde.getDropAction()==DnDConstants.ACTION_MOVE && draggedNodeParent != null) { ((DefaultTreeModel)tree.getModel()).nodeStructureChanged(draggedNodeParent); } } public final void dragEnter(DragSourceDragEvent dsde) { int action = dsde.getDropAction(); if (action == DnDConstants.ACTION_COPY) { dsde.getDragSourceContext().setCursor(DragSource.DefaultCopyDrop); } else { if (action == DnDConstants.ACTION_MOVE) { dsde.getDragSourceContext().setCursor(DragSource.DefaultMoveDrop); } else { dsde.getDragSourceContext().setCursor(DragSource.DefaultMoveNoDrop); } } } public final void dragOver(DragSourceDragEvent dsde) { int action = dsde.getDropAction(); if (action == DnDConstants.ACTION_COPY) { dsde.getDragSourceContext().setCursor(DragSource.DefaultCopyDrop); } else { if (action == DnDConstants.ACTION_MOVE) { dsde.getDragSourceContext().setCursor(DragSource.DefaultMoveDrop); } else { dsde.getDragSourceContext().setCursor(DragSource.DefaultMoveNoDrop); } } } public final void dropActionChanged(DragSourceDragEvent dsde) { int action = dsde.getDropAction(); if (action == DnDConstants.ACTION_COPY) { dsde.getDragSourceContext().setCursor(DragSource.DefaultCopyDrop); } else { if (action == DnDConstants.ACTION_MOVE) { dsde.getDragSourceContext().setCursor(DragSource.DefaultMoveDrop); } else { dsde.getDragSourceContext().setCursor(DragSource.DefaultMoveNoDrop); } } } public final void dragExit(DragSourceEvent dse) { dse.getDragSourceContext().setCursor(DragSource.DefaultMoveNoDrop); } /* Methods for DragGestureListener */ public final void dragGestureRecognized(DragGestureEvent dge) { TreePath path = tree.getSelectionPath(); if (path != null) { draggedNode = (MyDiskInfoTree)path.getLastPathComponent(); draggedNodeParent = (MyDiskInfoTree)draggedNode.getParent(); if (drawImage) { Rectangle pathBounds = tree.getPathBounds(path); //getpathbounds of selectionpath JComponent lbl = (JComponent)tree.getCellRenderer().getTreeCellRendererComponent(tree, draggedNode, false , tree.isExpanded(path),((DefaultTreeModel)tree.getModel()).isLeaf(path.getLastPathComponent()), 0,false);//returning the label lbl.setBounds(pathBounds);//setting bounds to lbl image = new BufferedImage(lbl.getWidth(), lbl.getHeight(), java.awt.image.BufferedImage.TYPE_INT_ARGB_PRE);//buffered image reference passing the label's ht and width Graphics2D graphics = image.createGraphics();//creating the graphics for buffered image graphics.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER, 0.5f)); //Sets the Composite for the Graphics2D context lbl.setOpaque(false); lbl.paint(graphics); //painting the graphics to label graphics.dispose(); } dragSource.startDrag(dge, DragSource.DefaultMoveNoDrop , image, new Point(0,0), new TransferableNode(draggedNode), this); } } /* Methods for DropTargetListener */ public final void dragEnter(DropTargetDragEvent dtde) { Point pt = dtde.getLocation(); int action = dtde.getDropAction(); if (drawImage) { paintImage(pt); } if (canPerformAction(tree, draggedNode, action, pt)) { dtde.acceptDrag(action); } else { dtde.rejectDrag(); } } public final void dragExit(DropTargetEvent dte) { if (drawImage) { clearImage(); } } public final void dragOver(DropTargetDragEvent dtde) { Point pt = dtde.getLocation(); int action = dtde.getDropAction(); tree.autoscroll(pt); if (drawImage) { paintImage(pt); } if (canPerformAction(tree, draggedNode, action, pt)) { dtde.acceptDrag(action); } else { dtde.rejectDrag(); } } public final void dropActionChanged(DropTargetDragEvent dtde) { Point pt = dtde.getLocation(); int action = dtde.getDropAction(); if (drawImage) { paintImage(pt); } if (canPerformAction(tree, draggedNode, action, pt)) { dtde.acceptDrag(action); } else { dtde.rejectDrag(); } } public final void drop(DropTargetDropEvent dtde) { try { if (drawImage) { clearImage(); } int action = dtde.getDropAction(); Transferable transferable = dtde.getTransferable(); Point pt = dtde.getLocation(); if (transferable.isDataFlavorSupported(TransferableNode.NODE_FLAVOR) && canPerformAction(tree, draggedNode, action, pt)) { TreePath pathTarget = tree.getPathForLocation(pt.x, pt.y); MyDiskInfoTree node = (MyDiskInfoTree) transferable.getTransferData(TransferableNode.NODE_FLAVOR); MyDiskInfoTree newParentNode =(MyDiskInfoTree)pathTarget.getLastPathComponent(); if (executeDrop(tree, node, newParentNode, action)) { dtde.acceptDrop(action); dtde.dropComplete(true); return; } } dtde.rejectDrop(); dtde.dropComplete(false); } catch (Exception e) { System.out.println(e); dtde.rejectDrop(); dtde.dropComplete(false); } } private final void paintImage(Point pt) { tree.paintImmediately(rect2D.getBounds()); rect2D.setRect((int) pt.getX(),(int) pt.getY(),image.getWidth(),image.getHeight()); tree.getGraphics().drawImage(image,(int) pt.getX(),(int) pt.getY(),tree); } private final void clearImage() { tree.paintImmediately(rect2D.getBounds()); } public abstract boolean canPerformAction(DNDTree target, MyDiskInfoTree draggedNode, int action, Point location); public abstract boolean executeDrop(DNDTree tree, MyDiskInfoTree draggedNode, MyDiskInfoTree newParentNode, int action); }