| /******************************************************************************* |
| * Copyright (c) 2000, 2008 IBM Corporation and others. |
| * All rights reserved. This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License v1.0 |
| * which accompanies this distribution, and is available at |
| * http://www.eclipse.org/legal/epl-v10.html |
| * |
| * Contributors: |
| * IBM Corporation - initial API and implementation |
| *******************************************************************************/ |
| package org.eclipse.swt.dnd; |
| |
| import org.eclipse.swt.*; |
| import org.eclipse.swt.graphics.*; |
| import org.eclipse.swt.internal.gtk.*; |
| import org.eclipse.swt.widgets.*; |
| |
| /** |
| * This class provides default implementations to display a source image |
| * when a drag is initiated from a <code>Tree</code>. |
| * |
| * <p>Classes that wish to provide their own source image for a <code>Tree</code> can |
| * extend <code>TreeDragSourceEffect</code> class and override the <code>TreeDragSourceEffect.dragStart</code> |
| * method and set the field <code>DragSourceEvent.image</code> with their own image.</p> |
| * |
| * Subclasses that override any methods of this class must call the corresponding |
| * <code>super</code> method to get the default drag under effect implementation. |
| * |
| * @see DragSourceEffect |
| * @see DragSourceEvent |
| * @see <a href="http://www.eclipse.org/swt/">Sample code and further information</a> |
| * |
| * @since 3.3 |
| */ |
| public class TreeDragSourceEffect extends DragSourceEffect { |
| Image dragSourceImage = null; |
| |
| /** |
| * Creates a new <code>TreeDragSourceEffect</code> to handle drag effect |
| * from the specified <code>Tree</code>. |
| * |
| * @param tree the <code>Tree</code> that the user clicks on to initiate the drag |
| */ |
| public TreeDragSourceEffect(Tree tree) { |
| super(tree); |
| } |
| |
| /** |
| * This implementation of <code>dragFinished</code> disposes the image |
| * that was created in <code>TreeDragSourceEffect.dragStart</code>. |
| * |
| * Subclasses that override this method should call <code>super.dragFinished(event)</code> |
| * to dispose the image in the default implementation. |
| * |
| * @param event the information associated with the drag finished event |
| */ |
| public void dragFinished(DragSourceEvent event) { |
| if (dragSourceImage != null) dragSourceImage.dispose(); |
| dragSourceImage = null; |
| } |
| |
| /** |
| * This implementation of <code>dragStart</code> will create a default |
| * image that will be used during the drag. The image should be disposed |
| * when the drag is completed in the <code>TreeDragSourceEffect.dragFinished</code> |
| * method. |
| * |
| * Subclasses that override this method should call <code>super.dragStart(event)</code> |
| * to use the image from the default implementation. |
| * |
| * @param event the information associated with the drag start event |
| */ |
| public void dragStart(DragSourceEvent event) { |
| event.image = getDragSourceImage(event); |
| } |
| |
| Image getDragSourceImage(DragSourceEvent event) { |
| if (dragSourceImage != null) dragSourceImage.dispose(); |
| dragSourceImage = null; |
| |
| Tree tree = (Tree) control; |
| if (OS.GTK_VERSION < OS.VERSION (2, 2, 0)) return null; |
| //TEMPORARY CODE |
| if (tree.isListening(SWT.EraseItem) || tree.isListening (SWT.PaintItem)) return null; |
| /* |
| * Bug in GTK. gtk_tree_selection_get_selected_rows() segmentation faults |
| * in versions smaller than 2.2.4 if the model is NULL. The fix is |
| * to give a valid pointer instead. |
| */ |
| int /*long*/ handle = tree.handle; |
| int /*long*/ selection = OS.gtk_tree_view_get_selection (handle); |
| int /*long*/ [] model = OS.GTK_VERSION < OS.VERSION (2, 2, 4) ? new int /*long*/ [1] : null; |
| int /*long*/ list = OS.gtk_tree_selection_get_selected_rows (selection, model); |
| if (list == 0) return null; |
| int count = Math.min(10, OS.g_list_length (list)); |
| |
| Display display = tree.getDisplay(); |
| if (count == 1) { |
| int /*long*/ path = OS.g_list_nth_data (list, 0); |
| int /*long*/ pixmap = OS.gtk_tree_view_create_row_drag_icon(handle, path); |
| dragSourceImage = Image.gtk_new(display, SWT.ICON, pixmap, 0); |
| } else { |
| int width = 0, height = 0; |
| int[] w = new int[1], h = new int[1]; |
| int[] yy = new int[count], hh = new int[count]; |
| int /*long*/ [] pixmaps = new int /*long*/ [count]; |
| GdkRectangle rect = new GdkRectangle (); |
| for (int i=0; i<count; i++) { |
| int /*long*/ path = OS.g_list_nth_data (list, i); |
| OS.gtk_tree_view_get_cell_area (handle, path, 0, rect); |
| pixmaps[i] = OS.gtk_tree_view_create_row_drag_icon(handle, path); |
| OS.gdk_drawable_get_size(pixmaps[i], w, h); |
| width = Math.max(width, w[0]); |
| height = rect.y + h[0] - yy[0]; |
| yy[i] = rect.y; |
| hh[i] = h[0]; |
| } |
| int /*long*/ source = OS.gdk_pixmap_new(OS.GDK_ROOT_PARENT(), width, height, -1); |
| int /*long*/ gcSource = OS.gdk_gc_new(source); |
| int /*long*/ mask = OS.gdk_pixmap_new(OS.GDK_ROOT_PARENT(), width, height, 1); |
| int /*long*/ gcMask = OS.gdk_gc_new(mask); |
| GdkColor color = new GdkColor(); |
| color.pixel = 0; |
| OS.gdk_gc_set_foreground(gcMask, color); |
| OS.gdk_draw_rectangle(mask, gcMask, 1, 0, 0, width, height); |
| color.pixel = 1; |
| OS.gdk_gc_set_foreground(gcMask, color); |
| for (int i=0; i<count; i++) { |
| OS.gdk_draw_drawable(source, gcSource, pixmaps[i], 0, 0, 0, yy[i] - yy[0], -1, -1); |
| OS.gdk_draw_rectangle(mask, gcMask, 1, 0, yy[i] - yy[0], width, hh[i]); |
| OS.g_object_unref(pixmaps[i]); |
| } |
| OS.g_object_unref(gcSource); |
| OS.g_object_unref(gcMask); |
| dragSourceImage = Image.gtk_new(display, SWT.ICON, source, mask); |
| } |
| OS.g_list_free (list); |
| |
| return dragSourceImage; |
| } |
| } |