Java tutorial
/******************************************************************************* * Copyright (c) 2004, 2015 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 * Tom Schindl <tom.schindl@bestsolution.at> - concept of ViewerRow, * refactoring (bug 153993), bug 167323, 191468, 205419 * Matthew Hall - bug 221988 * Pawel Piech, WindRiver - bug 296573 * Lars Vogel <Lars.Vogel@gmail.com> - Bug 430873 *******************************************************************************/ package org.eclipse.jface.viewers; import java.util.Arrays; import java.util.Iterator; import java.util.LinkedList; import java.util.List; import org.eclipse.jface.util.Policy; import org.eclipse.swt.SWT; import org.eclipse.swt.events.TreeEvent; import org.eclipse.swt.events.TreeListener; import org.eclipse.swt.graphics.Point; import org.eclipse.swt.widgets.Composite; import org.eclipse.swt.widgets.Control; import org.eclipse.swt.widgets.Item; import org.eclipse.swt.widgets.Tree; import org.eclipse.swt.widgets.TreeItem; import org.eclipse.swt.widgets.Widget; /** * A concrete viewer based on an SWT <code>Tree</code> control. * <p> * This class is not intended to be subclassed outside the viewer framework. It * is designed to be instantiated with a pre-existing SWT tree control and * configured with a domain-specific content provider, label provider, element * filter (optional), and element sorter (optional). * </p> * <p> * As of 3.2, TreeViewer supports multiple equal elements (each with a * different parent chain) in the tree. This support requires that clients * enable the element map by calling <code>setUseHashLookup(true)</code>. * </p> * <p> * Content providers for tree viewers must implement either the * {@link ITreeContentProvider} interface, (as of 3.2) the * {@link ILazyTreeContentProvider} interface, or (as of 3.3) the * {@link ILazyTreePathContentProvider}. If the content provider is an * <code>ILazyTreeContentProvider</code> or an * <code>ILazyTreePathContentProvider</code>, the underlying Tree must be * created using the {@link SWT#VIRTUAL} style bit, the tree viewer will not * support sorting or filtering, and hash lookup must be enabled by calling * {@link #setUseHashlookup(boolean)}. * </p> * <p> * Users setting up an editable tree with more than 1 column <b>have</b> to pass the * SWT.FULL_SELECTION style bit * </p> * @noextend This class is not intended to be subclassed by clients. */ public class TreeViewer extends AbstractTreeViewer { private static final String VIRTUAL_DISPOSE_KEY = Policy.JFACE + ".DISPOSE_LISTENER"; //$NON-NLS-1$ /** * This viewer's control. */ private Tree tree; /** * Flag for whether the tree has been disposed of. */ private boolean treeIsDisposed = false; private boolean contentProviderIsLazy; private boolean contentProviderIsTreeBased; /** * The row object reused */ private TreeViewerRow cachedRow; /** * true if we are inside a preservingSelection() call */ private boolean insidePreservingSelection; /** * Creates a tree viewer on a newly-created tree control under the given * parent. The tree control is created using the SWT style bits * <code>MULTI, H_SCROLL, V_SCROLL,</code> and <code>BORDER</code>. The * viewer has no input, no content provider, a default label provider, no * sorter, and no filters. * * @param parent * the parent control */ public TreeViewer(Composite parent) { this(parent, SWT.MULTI | SWT.H_SCROLL | SWT.V_SCROLL | SWT.BORDER); } /** * Creates a tree viewer on a newly-created tree control under the given * parent. The tree control is created using the given SWT style bits. The * viewer has no input, no content provider, a default label provider, no * sorter, and no filters. * * @param parent * the parent control * @param style * the SWT style bits used to create the tree. */ public TreeViewer(Composite parent, int style) { this(new Tree(parent, style)); } /** * Creates a tree viewer on the given tree control. The viewer has no input, * no content provider, a default label provider, no sorter, and no filters. * * @param tree * the tree control */ public TreeViewer(Tree tree) { super(); this.tree = tree; hookControl(tree); } @Override protected void addTreeListener(Control c, TreeListener listener) { ((Tree) c).addTreeListener(listener); } @Override protected Widget getColumnViewerOwner(int columnIndex) { if (columnIndex < 0 || (columnIndex > 0 && columnIndex >= getTree().getColumnCount())) { return null; } if (getTree().getColumnCount() == 0)// Hang it off the table if it return getTree(); return getTree().getColumn(columnIndex); } @Override protected Item[] getChildren(Widget o) { if (o instanceof TreeItem) { return ((TreeItem) o).getItems(); } if (o instanceof Tree) { return ((Tree) o).getItems(); } return null; } @Override public Control getControl() { return tree; } @Override protected boolean getExpanded(Item item) { return ((TreeItem) item).getExpanded(); } @Override protected Item getItemAt(Point p) { TreeItem[] selection = tree.getSelection(); if (selection.length == 1) { int columnCount = tree.getColumnCount(); for (int i = 0; i < columnCount; i++) { if (selection[0].getBounds(i).contains(p)) { return selection[0]; } } } return getTree().getItem(p); } @Override protected int getItemCount(Control widget) { return ((Tree) widget).getItemCount(); } @Override protected int getItemCount(Item item) { return ((TreeItem) item).getItemCount(); } @Override protected Item[] getItems(Item item) { return ((TreeItem) item).getItems(); } /** * The tree viewer implementation of this <code>Viewer</code> framework * method ensures that the given label provider is an instance of either * <code>ITableLabelProvider</code> or <code>ILabelProvider</code>. If * it is an <code>ITableLabelProvider</code>, then it provides a separate * label text and image for each column. If it is an * <code>ILabelProvider</code>, then it provides only the label text and * image for the first column, and any remaining columns are blank. */ @Override public IBaseLabelProvider getLabelProvider() { return super.getLabelProvider(); } @Override protected Item getParentItem(Item item) { return ((TreeItem) item).getParentItem(); } @Override protected Item[] getSelection(Control widget) { return ((Tree) widget).getSelection(); } /** * Returns this tree viewer's tree control. * * @return the tree control */ public Tree getTree() { return tree; } @Override protected void hookControl(Control control) { super.hookControl(control); Tree treeControl = (Tree) control; if ((treeControl.getStyle() & SWT.VIRTUAL) != 0) { treeControl.addDisposeListener(e -> { treeIsDisposed = true; unmapAllElements(); }); treeControl.addListener(SWT.SetData, event -> { if (contentProviderIsLazy) { TreeItem item = (TreeItem) event.item; TreeItem parentItem = item.getParentItem(); int index = event.index; virtualLazyUpdateWidget(parentItem == null ? (Widget) getTree() : parentItem, index); } }); } } @Override protected ColumnViewerEditor createViewerEditor() { return new TreeViewerEditor(this, null, new ColumnViewerEditorActivationStrategy(this), ColumnViewerEditor.DEFAULT); } @Override protected Item newItem(Widget parent, int flags, int ix) { TreeItem item; if (parent instanceof TreeItem) { item = (TreeItem) createNewRowPart(getViewerRowFromItem(parent), flags, ix).getItem(); } else { item = (TreeItem) createNewRowPart(null, flags, ix).getItem(); } return item; } @Override protected void removeAll(Control widget) { ((Tree) widget).removeAll(); } @Override protected void setExpanded(Item node, boolean expand) { ((TreeItem) node).setExpanded(expand); if (contentProviderIsLazy) { // force repaints to happen getControl().update(); } } @Override protected void setSelection(List items) { Item[] current = getSelection(getTree()); // Don't bother resetting the same selection if (isSameSelection(items, current)) { return; } TreeItem[] newItems = new TreeItem[items.size()]; items.toArray(newItems); getTree().setSelection(newItems); } @Override protected void showItem(Item item) { getTree().showItem((TreeItem) item); } @Override protected Item getChild(Widget widget, int index) { if (widget instanceof TreeItem) { return ((TreeItem) widget).getItem(index); } if (widget instanceof Tree) { return ((Tree) widget).getItem(index); } return null; } @Override protected void assertContentProviderType(IContentProvider provider) { if (provider instanceof ILazyTreeContentProvider || provider instanceof ILazyTreePathContentProvider) { return; } super.assertContentProviderType(provider); } @Override protected Object[] getRawChildren(Object parent) { if (contentProviderIsLazy) { return new Object[0]; } return super.getRawChildren(parent); } @Override void preservingSelection(Runnable updateCode, boolean reveal) { if (insidePreservingSelection || !getPreserveSelection()) { // avoid preserving the selection if called reentrantly, // see bug 172640 updateCode.run(); return; } insidePreservingSelection = true; try { super.preservingSelection(updateCode, reveal); } finally { insidePreservingSelection = false; } } /** * For a TreeViewer with a tree with the VIRTUAL style bit set, set the * number of children of the given element or tree path. To set the number * of children of the invisible root of the tree, you can pass the input * object or an empty tree path. * * @param elementOrTreePath * the element, or tree path * @param count * * @since 3.2 */ public void setChildCount(final Object elementOrTreePath, final int count) { if (checkBusy()) return; preservingSelection(() -> { if (internalIsInputOrEmptyPath(elementOrTreePath)) { getTree().setItemCount(count); return; } Widget[] items = internalFindItems(elementOrTreePath); for (Widget item : items) { TreeItem treeItem = (TreeItem) item; treeItem.setItemCount(count); } }); } /** * For a TreeViewer with a tree with the VIRTUAL style bit set, replace the * given parent's child at index with the given element. If the given parent * is this viewer's input or an empty tree path, this will replace the root * element at the given index. * <p> * This method should be called by implementers of ILazyTreeContentProvider * to populate this viewer. * </p> * * @param parentElementOrTreePath * the parent of the element that should be updated, or the tree * path to that parent * @param index * the index in the parent's children * @param element * the new element * * @see #setChildCount(Object, int) * @see ILazyTreeContentProvider * @see ILazyTreePathContentProvider * * @since 3.2 */ public void replace(final Object parentElementOrTreePath, final int index, final Object element) { if (checkBusy()) return; Item[] selectedItems = getSelection(getControl()); TreeSelection selection = (TreeSelection) getSelection(); Widget[] itemsToDisassociate; if (parentElementOrTreePath instanceof TreePath) { TreePath elementPath = ((TreePath) parentElementOrTreePath).createChildPath(element); itemsToDisassociate = internalFindItems(elementPath); } else { itemsToDisassociate = internalFindItems(element); } if (internalIsInputOrEmptyPath(parentElementOrTreePath)) { if (index < tree.getItemCount()) { TreeItem item = tree.getItem(index); selection = adjustSelectionForReplace(selectedItems, selection, item, element, getRoot()); // disassociate any different item that represents the // same element under the same parent (the tree) for (Widget widget : itemsToDisassociate) { if (widget instanceof TreeItem) { TreeItem itemToDisassociate = (TreeItem) widget; if (itemToDisassociate != item && itemToDisassociate.getParentItem() == null) { int indexToDisassociate = getTree().indexOf(itemToDisassociate); disassociate(itemToDisassociate); getTree().clear(indexToDisassociate, true); } } } Object oldData = item.getData(); updateItem(item, element); if (!TreeViewer.this.equals(oldData, element)) { item.clearAll(true); } } } else { Widget[] parentItems = internalFindItems(parentElementOrTreePath); for (Widget widget : parentItems) { TreeItem parentItem = (TreeItem) widget; if (index < parentItem.getItemCount()) { TreeItem item = parentItem.getItem(index); selection = adjustSelectionForReplace(selectedItems, selection, item, element, parentItem.getData()); // disassociate any different item that represents the // same element under the same parent (the tree) for (Widget widgetToDisassociate : itemsToDisassociate) { if (widgetToDisassociate instanceof TreeItem) { TreeItem itemToDisassociate = (TreeItem) widgetToDisassociate; if (itemToDisassociate != item && itemToDisassociate.getParentItem() == parentItem) { int indexToDisaccociate = parentItem.indexOf(itemToDisassociate); disassociate(itemToDisassociate); parentItem.clear(indexToDisaccociate, true); } } } Object oldData = item.getData(); updateItem(item, element); if (!TreeViewer.this.equals(oldData, element)) { item.clearAll(true); } } } } // Restore the selection if we are not already in a nested preservingSelection: if (!insidePreservingSelection) { setSelectionToWidget(selection, false); // send out notification if old and new differ ISelection newSelection = getSelection(); if (!newSelection.equals(selection)) { handleInvalidSelection(selection, newSelection); } } } /** * Fix for bug 185673: If the currently replaced item was selected, add it * to the selection that is being restored. Only do this if its getData() is * currently null * * @param selectedItems * @param selection * @param item * @param element * @return the adjusted selection */ private TreeSelection adjustSelectionForReplace(Item[] selectedItems, TreeSelection selection, TreeItem item, Object element, Object parentElement) { if (item.getData() != null || selectedItems.length == selection.size() || parentElement == null) { // Don't do anything - we are not seeing an instance of bug 185673 return selection; } for (Item selectedItem : selectedItems) { if (item == selectedItem) { // The current item was selected, but its data is null. // The data will be replaced by the given element, so to keep // it selected, we have to add it to the selection. TreePath[] originalPaths = selection.getPaths(); int length = originalPaths.length; TreePath[] paths = new TreePath[length + 1]; System.arraycopy(originalPaths, 0, paths, 0, length); // set the element temporarily so that we can call getTreePathFromItem item.setData(element); paths[length] = getTreePathFromItem(item); item.setData(null); return new TreeSelection(paths, selection.getElementComparer()); } } // The item was not selected, return the given selection return selection; } @Override public boolean isExpandable(Object element) { if (contentProviderIsLazy) { TreeItem treeItem = (TreeItem) internalExpand(element, false); if (treeItem == null) { return false; } virtualMaterializeItem(treeItem); return treeItem.getItemCount() > 0; } return super.isExpandable(element); } @Override protected Object getParentElement(Object element) { boolean oldBusy = isBusy(); setBusy(true); try { if (contentProviderIsLazy && !contentProviderIsTreeBased && !(element instanceof TreePath)) { ILazyTreeContentProvider lazyTreeContentProvider = (ILazyTreeContentProvider) getContentProvider(); return lazyTreeContentProvider.getParent(element); } if (contentProviderIsLazy && contentProviderIsTreeBased && !(element instanceof TreePath)) { ILazyTreePathContentProvider lazyTreePathContentProvider = (ILazyTreePathContentProvider) getContentProvider(); TreePath[] parents = lazyTreePathContentProvider.getParents(element); if (parents != null && parents.length > 0) { return parents[0]; } } return super.getParentElement(element); } finally { setBusy(oldBusy); } } @Override void createChildren(Widget widget, boolean materialize) { if (contentProviderIsLazy) { Object element = widget.getData(); if (element == null && widget instanceof TreeItem) { // parent has not been materialized virtualMaterializeItem((TreeItem) widget); // try getting the element now that updateElement was called element = widget.getData(); } if (element == null) { // give up because the parent is still not materialized return; } Item[] children = getChildren(widget); if (children.length == 1 && children[0].getData() == null) { // found a dummy node virtualLazyUpdateChildCount(widget, children.length); children = getChildren(widget); } // touch all children to make sure they are materialized for (int i = 0; i < children.length; i++) { if (children[i].getData() == null) { if (materialize) { virtualLazyUpdateWidget(widget, i); } else { ((TreeItem) children[i]).clearAll(true); } } } return; } super.createChildren(widget, materialize); } @Override protected void internalAdd(Widget widget, Object parentElement, Object[] childElements) { if (contentProviderIsLazy) { if (widget instanceof TreeItem) { TreeItem ti = (TreeItem) widget; int count = ti.getItemCount() + childElements.length; ti.setItemCount(count); ti.clearAll(false); } else { Tree t = (Tree) widget; t.setItemCount(t.getItemCount() + childElements.length); t.clearAll(false); } return; } super.internalAdd(widget, parentElement, childElements); } private void virtualMaterializeItem(TreeItem treeItem) { if (treeItem.getData() != null) { // already materialized return; } if (!contentProviderIsLazy) { return; } int index; Widget parent = treeItem.getParentItem(); if (parent == null) { parent = treeItem.getParent(); } Object parentElement = parent.getData(); if (parentElement != null) { if (parent instanceof Tree) { index = ((Tree) parent).indexOf(treeItem); } else { index = ((TreeItem) parent).indexOf(treeItem); } virtualLazyUpdateWidget(parent, index); } } @Override protected void internalRefreshStruct(Widget widget, Object element, boolean updateLabels) { if (contentProviderIsLazy) { // clear all starting with the given widget if (widget instanceof Tree) { ((Tree) widget).clearAll(true); } else if (widget instanceof TreeItem) { ((TreeItem) widget).clearAll(true); } int index = 0; Widget parent = null; if (widget instanceof TreeItem) { TreeItem treeItem = (TreeItem) widget; parent = treeItem.getParentItem(); if (parent == null) { parent = treeItem.getParent(); } if (parent instanceof Tree) { index = ((Tree) parent).indexOf(treeItem); } else { index = ((TreeItem) parent).indexOf(treeItem); } } virtualRefreshExpandedItems(parent, widget, element, index); return; } super.internalRefreshStruct(widget, element, updateLabels); } /** * Traverses the visible (expanded) part of the tree and updates child * counts. * * @param parent the parent of the widget, or <code>null</code> if the widget is the tree * @param widget * @param element * @param index the index of the widget in the children array of its parent, or 0 if the widget is the tree */ private void virtualRefreshExpandedItems(Widget parent, Widget widget, Object element, int index) { if (widget instanceof Tree) { if (element == null) { ((Tree) widget).setItemCount(0); return; } virtualLazyUpdateChildCount(widget, getChildren(widget).length); } else if (((TreeItem) widget).getExpanded()) { // prevent SetData callback ((TreeItem) widget).setText(" "); //$NON-NLS-1$ virtualLazyUpdateWidget(parent, index); } else { return; } Item[] items = getChildren(widget); for (int i = 0; i < items.length; i++) { Item item = items[i]; Object data = item.getData(); virtualRefreshExpandedItems(widget, item, data, i); } } /* * To unmap elements correctly, we need to register a dispose listener with * the item if the tree is virtual. */ @Override protected void mapElement(Object element, final Widget item) { super.mapElement(element, item); // make sure to unmap elements if the tree is virtual if ((getTree().getStyle() & SWT.VIRTUAL) != 0) { // only add a dispose listener if item hasn't already on assigned // because it is reused if (item.getData(VIRTUAL_DISPOSE_KEY) == null) { item.setData(VIRTUAL_DISPOSE_KEY, Boolean.TRUE); item.addDisposeListener(e -> { if (!treeIsDisposed) { Object data = item.getData(); if (usingElementMap() && data != null) { unmapElement(data, item); } } }); } } } @Override protected ViewerRow getViewerRowFromItem(Widget item) { if (cachedRow == null) { cachedRow = new TreeViewerRow((TreeItem) item); } else { cachedRow.setItem((TreeItem) item); } return cachedRow; } /** * Create a new ViewerRow at rowIndex * * @param parent * @param style * @param rowIndex * @return ViewerRow */ private ViewerRow createNewRowPart(ViewerRow parent, int style, int rowIndex) { if (parent == null) { if (rowIndex >= 0) { return getViewerRowFromItem(new TreeItem(tree, style, rowIndex)); } return getViewerRowFromItem(new TreeItem(tree, style)); } if (rowIndex >= 0) { return getViewerRowFromItem(new TreeItem((TreeItem) parent.getItem(), SWT.NONE, rowIndex)); } return getViewerRowFromItem(new TreeItem((TreeItem) parent.getItem(), SWT.NONE)); } @Override protected void internalInitializeTree(Control widget) { if (contentProviderIsLazy) { if (widget instanceof Tree && widget.getData() != null) { virtualLazyUpdateChildCount(widget, 0); return; } } super.internalInitializeTree(tree); } @Override protected void updatePlus(Item item, Object element) { if (contentProviderIsLazy) { Object data = item.getData(); int itemCount = 0; if (data != null) { // item is already materialized itemCount = ((TreeItem) item).getItemCount(); } virtualLazyUpdateHasChildren(item, itemCount); } else { super.updatePlus(item, element); } } /** * Removes the element at the specified index of the parent. The selection is updated if required. * * @param parentOrTreePath the parent element, the input element, or a tree path to the parent element * @param index child index * @since 3.3 */ public void remove(final Object parentOrTreePath, final int index) { if (checkBusy()) return; final List oldSelection = new LinkedList(Arrays.asList(((TreeSelection) getSelection()).getPaths())); preservingSelection(() -> { TreePath removedPath = null; if (internalIsInputOrEmptyPath(parentOrTreePath)) { Tree tree = (Tree) getControl(); if (index < tree.getItemCount()) { TreeItem item1 = tree.getItem(index); if (item1.getData() != null) { removedPath = getTreePathFromItem(item1); disassociate(item1); } item1.dispose(); } } else { Widget[] parentItems = internalFindItems(parentOrTreePath); for (Widget parentWidget : parentItems) { TreeItem parentItem = (TreeItem) parentWidget; if (parentItem.isDisposed()) continue; if (index < parentItem.getItemCount()) { TreeItem item2 = parentItem.getItem(index); if (item2.getData() == null) { // If getData()==null and index == 0, and the // parent item is collapsed, then we are // being asked to remove the dummy node. We'll // just ignore the request to remove the dummy // node (bug 292322 and bug 296573). if (index > 0 || parentItem.getExpanded()) { item2.dispose(); } } else { removedPath = getTreePathFromItem(item2); disassociate(item2); item2.dispose(); } } } } if (removedPath != null) { boolean removed = false; for (Iterator it = oldSelection.iterator(); it.hasNext();) { TreePath path = (TreePath) it.next(); if (path.startsWith(removedPath, getComparer())) { it.remove(); removed = true; } } if (removed) { setSelection( new TreeSelection((TreePath[]) oldSelection.toArray(new TreePath[oldSelection.size()]), getComparer()), false); } } }); } @Override protected void handleTreeExpand(TreeEvent event) { // Fix for Bug 271744 because windows expanding doesn't fire a focus lost if (isCellEditorActive()) { applyEditorValue(); } if (contentProviderIsLazy) { if (event.item.getData() != null) { Item[] children = getChildren(event.item); if (children.length == 1 && children[0].getData() == null) { // we have a dummy child node, ask for an updated child // count virtualLazyUpdateChildCount(event.item, children.length); } fireTreeExpanded(new TreeExpansionEvent(this, event.item.getData())); } return; } super.handleTreeExpand(event); } @Override protected void handleTreeCollapse(TreeEvent event) { // Fix for Bug 271744 because windows is firing collapse before // focus lost event if (isCellEditorActive()) { applyEditorValue(); } super.handleTreeCollapse(event); } /** * Sets the content provider used by this <code>TreeViewer</code>. * <p> * Content providers for tree viewers must implement either * {@link ITreeContentProvider}, or {@link ITreePathContentProvider}, or * {@link ILazyTreeContentProvider}, or * {@link ILazyTreePathContentProvider}. */ @Override public void setContentProvider(IContentProvider provider) { contentProviderIsLazy = (provider instanceof ILazyTreeContentProvider) || (provider instanceof ILazyTreePathContentProvider); contentProviderIsTreeBased = provider instanceof ILazyTreePathContentProvider; super.setContentProvider(provider); } /** * For a TreeViewer with a tree with the VIRTUAL style bit set, inform the * viewer about whether the given element or tree path has children. Avoid * calling this method if the number of children has already been set. * * @param elementOrTreePath * the element, or tree path * @param hasChildren * * @since 3.3 */ public void setHasChildren(final Object elementOrTreePath, final boolean hasChildren) { if (checkBusy()) return; preservingSelection(() -> { if (internalIsInputOrEmptyPath(elementOrTreePath)) { if (hasChildren) { virtualLazyUpdateChildCount(getTree(), getChildren(getTree()).length); } else { setChildCount(elementOrTreePath, 0); } return; } Widget[] items = internalFindItems(elementOrTreePath); for (Widget widget : items) { TreeItem item = (TreeItem) widget; if (!hasChildren) { item.setItemCount(0); } else { if (!item.getExpanded()) { item.setItemCount(1); TreeItem child = item.getItem(0); if (child.getData() != null) { disassociate(child); } item.clear(0, true); } else { virtualLazyUpdateChildCount(item, item.getItemCount()); } } } }); } /** * Update the widget at index. * @param widget * @param index */ private void virtualLazyUpdateWidget(Widget widget, int index) { boolean oldBusy = isBusy(); setBusy(false); try { if (contentProviderIsTreeBased) { TreePath treePath; if (widget instanceof Item) { if (widget.getData() == null) { // we need to materialize the parent first // see bug 167668 // however, that would be too risky // see bug 182782 and bug 182598 // so we just ignore this call altogether // and don't do this: virtualMaterializeItem((TreeItem) widget); return; } treePath = getTreePathFromItem((Item) widget); } else { treePath = TreePath.EMPTY; } ((ILazyTreePathContentProvider) getContentProvider()).updateElement(treePath, index); } else { ((ILazyTreeContentProvider) getContentProvider()).updateElement(widget.getData(), index); } } finally { setBusy(oldBusy); } } /** * Update the child count * @param widget * @param currentChildCount */ private void virtualLazyUpdateChildCount(Widget widget, int currentChildCount) { boolean oldBusy = isBusy(); setBusy(false); try { if (contentProviderIsTreeBased) { TreePath treePath; if (widget instanceof Item) { treePath = getTreePathFromItem((Item) widget); } else { treePath = TreePath.EMPTY; } ((ILazyTreePathContentProvider) getContentProvider()).updateChildCount(treePath, currentChildCount); } else { ((ILazyTreeContentProvider) getContentProvider()).updateChildCount(widget.getData(), currentChildCount); } } finally { setBusy(oldBusy); } } /** * Update the item with the current child count. * @param item * @param currentChildCount */ private void virtualLazyUpdateHasChildren(Item item, int currentChildCount) { boolean oldBusy = isBusy(); setBusy(false); try { if (contentProviderIsTreeBased) { TreePath treePath; treePath = getTreePathFromItem(item); if (currentChildCount == 0 || !((TreeItem) item).getExpanded()) { // item is not expanded (but may have a plus currently) ((ILazyTreePathContentProvider) getContentProvider()).updateHasChildren(treePath); } else { ((ILazyTreePathContentProvider) getContentProvider()).updateChildCount(treePath, currentChildCount); } } else { ((ILazyTreeContentProvider) getContentProvider()).updateChildCount(item.getData(), currentChildCount); } } finally { setBusy(oldBusy); } } @Override protected void disassociate(Item item) { if (contentProviderIsLazy) { // avoid causing a callback: item.setText(" "); //$NON-NLS-1$ } super.disassociate(item); } @Override protected int doGetColumnCount() { return tree.getColumnCount(); } /** * Sets a new selection for this viewer and optionally makes it visible. * <p> * <b>Currently the <code>reveal</code> parameter is not honored because * {@link Tree} does not provide an API to only select an item without * scrolling it into view</b> * </p> * * @param selection * the new selection * @param reveal * <code>true</code> if the selection is to be made visible, * and <code>false</code> otherwise */ @Override public void setSelection(ISelection selection, boolean reveal) { super.setSelection(selection, reveal); } @Override public void editElement(Object element, int column) { if (element instanceof TreePath) { try { getControl().setRedraw(false); setSelection(new TreeSelection((TreePath) element)); TreeItem[] items = tree.getSelection(); if (items.length == 1) { ViewerRow row = getViewerRowFromItem(items[0]); if (row != null) { ViewerCell cell = row.getCell(column); if (cell != null) { triggerEditorActivationEvent(new ColumnViewerEditorActivationEvent(cell)); } } } } finally { getControl().setRedraw(true); } } else { super.editElement(element, column); } } }