--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dwtx/jface/viewers/ILazyTreePathContentProvider.d	Mon Mar 31 00:47:19 2008 +0200
@@ -0,0 +1,101 @@
+/*******************************************************************************
+ * Copyright (c) 2005, 2006 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
+ * Port to the D programming language:
+ *     Frank Benoit <benoit@tionex.de>
+ *******************************************************************************/
+module dwtx.jface.viewers.ILazyTreePathContentProvider;
+
+import dwtx.jface.viewers.IContentProvider;
+import dwtx.jface.viewers.TreePath;
+
+import dwt.dwthelper.utils;
+
+/**
+ * The ILazyTreePathContentProvider is a tree path-based content provider for
+ * tree viewers created using the DWT.VIRTUAL flag that only wish to return
+ * their contents as they are queried.
+ *
+ * @since 3.3
+ */
+public interface ILazyTreePathContentProvider : IContentProvider {
+    /**
+     * Called when a previously-blank item becomes visible in the TreeViewer. If
+     * the content provider knows the child element for the given parent at this
+     * index, it should respond by calling
+     * {@link TreeViewer#replace(Object, int, Object)}. The content provider
+     * should also update the child count for any replaced element by calling
+     * {@link TreeViewer#setChildCount(Object, int)}. If the given current child
+     * count is already correct, setChildCount does not have to be called since
+     * a call to replace will not change the child count.
+     *
+     * <strong>NOTE</strong> #updateElement(int index) can be used to determine
+     * selection values. If TableViewer#replace(Object, int) is not called
+     * before returning from this method, selections may have missing or stale
+     * elements. In this situation it is suggested that the selection is asked
+     * for again after replace() has been called.
+     *
+     * @param parentPath
+     *            The tree path of parent of the element, or if the
+     *            element to update is a root element, an empty tree path
+     * @param index
+     *            The index of the element to update in the tree
+     */
+    public void updateElement(TreePath parentPath, int index);
+
+    /**
+     * Called when the TreeViewer needs an up-to-date child count for the given
+     * tree path, for example from {@link TreeViewer#refresh()} and
+     * {@link TreeViewer#setInput(Object)}. If the content provider knows the
+     * element at the given tree path, it should respond by calling
+     * {@link TreeViewer#setChildCount(Object, int)}. If the given current
+     * child count is already correct, no action has to be taken by this content
+     * provider.
+     *
+     * @param treePath
+     *            The tree path for which an up-to-date child count is needed, or
+     *            if the number of root elements is requested, the empty tree path
+     * @param currentChildCount
+     *            The current child count for the element that needs updating
+     */
+    public void updateChildCount(TreePath treePath, int currentChildCount);
+
+    /**
+     * Called when the TreeViewer needs up-to-date information whether the node
+     * at the given tree path can be expanded. If the content provider knows the
+     * element at the given tree path, it should respond by calling
+     * {@link TreeViewer#setHasChildren(Object, bool)}. The content provider
+     * may also choose to call {@link TreeViewer#setChildCount(Object, int)}
+     * instead if it knows the number of children.
+     *
+     * <p>
+     * Intended as an optimization for when the viewer does not need the actual
+     * children. Clients may be able to implement this more efficiently than
+     * <code>updateChildCount</code>.
+     * </p>
+     *
+     * @param path
+     *            The tree path for which up-to-date information about children
+     *            is needed
+     */
+    public void updateHasChildren(TreePath path);
+
+    /**
+     * Return the possible parent paths for the given element. An empty array
+     * can be returned if the paths cannot be computed. In this case the
+     * tree-structured viewer can't expand a given node correctly if requested.
+     * If the element is a potential child of the input of the viewer, an empty
+     * tree path should be an entry in the returned array.
+     *
+     * @param element
+     *            the element
+     * @return the possible parent paths for the given element
+     */
+    public TreePath[] getParents(Object element);
+}