org.eclipse.jface.viewers.AbstractTreeViewer Maven / Gradle / Ivy
/*******************************************************************************
* Copyright (c) 2000, 2010 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 - bug 153993, bug 167323, bug 175192
* Lasse Knudsen, bug 205700
* Micah Hainline, bug 210448
* Michael Schneider, bug 210747
* Bruce Sutton, bug 221768
* Matthew Hall, bug 221988
*******************************************************************************/
package org.eclipse.jface.viewers;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import org.eclipse.core.runtime.Assert;
import org.eclipse.core.runtime.ListenerList;
import org.eclipse.jface.internal.util.SerializableListenerList;
import org.eclipse.jface.util.SafeRunnable;
import org.eclipse.swt.SWT;
import org.eclipse.swt.custom.BusyIndicator;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.events.SelectionListener;
import org.eclipse.swt.events.TreeEvent;
import org.eclipse.swt.events.TreeListener;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Item;
import org.eclipse.swt.widgets.Widget;
/**
* Abstract base implementation for tree-structure-oriented viewers (trees and
* table trees).
*
* Nodes in the tree can be in either an expanded or a collapsed state,
* depending on whether the children on a node are visible. This class
* introduces public methods for controlling the expanding and collapsing of
* nodes.
*
*
* As of 3.2, AbstractTreeViewer supports multiple equal elements (each with a
* different parent chain) in the tree. This support requires that clients
* enable the element map by calling setUseHashLookup(true).
*
*
* Content providers for abstract tree viewers must implement one of the
* interfaces ITreeContentProvider or (as of 3.2, to support
* multiple equal elements) ITreePathContentProvider.
*
*
* @see TreeViewer
*/
public abstract class AbstractTreeViewer extends ColumnViewer {
/**
* Constant indicating that all levels of the tree should be expanded or
* collapsed.
*
* @see #expandToLevel(int)
* @see #collapseToLevel(Object, int)
*/
public static final int ALL_LEVELS = -1;
/**
* List of registered tree listeners (element type:
* TreeListener).
*/
private ListenerList treeListeners = new SerializableListenerList();
/**
* The level to which the tree is automatically expanded each time the
* viewer's input is changed (that is, by setInput). A value
* of 0 means that auto-expand is off.
*
* @see #setAutoExpandLevel
*/
private int expandToLevel = 0;
/**
* Safe runnable used to update an item.
*/
class UpdateItemSafeRunnable extends SafeRunnable {
private Object element;
private Item item;
UpdateItemSafeRunnable(Item item, Object element) {
this.item = item;
this.element = element;
}
public void run() {
doUpdateItem(item, element);
}
}
/**
* Creates an abstract tree viewer. The viewer has no input, no content
* provider, a default label provider, no sorter, no filters, and has
* auto-expand turned off.
*/
protected AbstractTreeViewer() {
// do nothing
}
/**
* Adds the given child elements to this viewer as children of the given
* parent element. If this viewer does not have a sorter, the elements are
* added at the end of the parent's list of children in the order given;
* otherwise, the elements are inserted at the appropriate positions.
*
* This method should be called (by the content provider) when elements have
* been added to the model, in order to cause the viewer to accurately
* reflect the model. This method only affects the viewer, not the model.
*
*
* @param parentElementOrTreePath
* the parent element
* @param childElements
* the child elements to add
*/
public void add(Object parentElementOrTreePath, Object[] childElements) {
Assert.isNotNull(parentElementOrTreePath);
assertElementsNotNull(childElements);
if (checkBusy())
return;
Widget[] widgets = internalFindItems(parentElementOrTreePath);
// If parent hasn't been realized yet, just ignore the add.
if (widgets.length == 0) {
return;
}
for (int i = 0; i < widgets.length; i++) {
internalAdd(widgets[i], parentElementOrTreePath, childElements);
}
}
/**
* Find the items for the given element of tree path
*
* @param parentElementOrTreePath
* the element or tree path
* @return the items for that element
*
* @since 1.0
*/
final protected Widget[] internalFindItems(Object parentElementOrTreePath) {
Widget[] widgets;
if (parentElementOrTreePath instanceof TreePath) {
TreePath path = (TreePath) parentElementOrTreePath;
Widget w = internalFindItem(path);
if (w == null) {
widgets = new Widget[] {};
} else {
widgets = new Widget[] { w };
}
} else {
widgets = findItems(parentElementOrTreePath);
}
return widgets;
}
/**
* Return the item at the given path or null
*
* @param path
* the path
* @return {@link Widget} the item at that path
*/
private Widget internalFindItem(TreePath path) {
Widget[] widgets = findItems(path.getLastSegment());
for (int i = 0; i < widgets.length; i++) {
Widget widget = widgets[i];
if (widget instanceof Item) {
Item item = (Item) widget;
TreePath p = getTreePathFromItem(item);
if (p.equals(path)) {
return widget;
}
}
}
return null;
}
/**
* Adds the given child elements to this viewer as children of the given
* parent element.
*
* EXPERIMENTAL. Not to be used except by JDT. This method was added to
* support JDT's explorations into grouping by working sets. This method
* cannot be removed without breaking binary backwards compatibility, but
* should not be called by clients.
*
*
* @param widget
* the widget for the parent element
* @param parentElementOrTreePath
* the parent element
* @param childElements
* the child elements to add
* @since 1.0
*/
protected void internalAdd(Widget widget, Object parentElementOrTreePath,
Object[] childElements) {
Object parent;
TreePath path;
if (parentElementOrTreePath instanceof TreePath) {
path = (TreePath) parentElementOrTreePath;
parent = path.getLastSegment();
} else {
parent = parentElementOrTreePath;
path = null;
}
// optimization!
// if the widget is not expanded we just invalidate the subtree
if (widget instanceof Item) {
Item ti = (Item) widget;
if (!getExpanded(ti)) {
boolean needDummy = isExpandable(ti, path, parent);
boolean haveDummy = false;
// remove all children
Item[] items = getItems(ti);
for (int i = 0; i < items.length; i++) {
if (items[i].getData() != null) {
disassociate(items[i]);
items[i].dispose();
} else {
if (needDummy && !haveDummy) {
haveDummy = true;
} else {
items[i].dispose();
}
}
}
// append a dummy if necessary
if (needDummy && !haveDummy) {
newItem(ti, SWT.NULL, -1);
}
return;
}
}
if (childElements.length > 0) {
// TODO: Add filtering back?
Object[] filtered = filter(parentElementOrTreePath, childElements);
ViewerComparator comparator = getComparator();
if (comparator != null) {
if (comparator instanceof TreePathViewerSorter) {
TreePathViewerSorter tpvs = (TreePathViewerSorter) comparator;
if (path == null) {
path = internalGetSorterParentPath(widget, comparator);
}
tpvs.sort(this, path, filtered);
} else {
comparator.sort(this, filtered);
}
}
createAddedElements(widget, filtered);
}
}
/**
* Filter the children elements.
*
* @param parentElementOrTreePath
* the parent element or path
* @param elements
* the child elements
* @return the filter list of children
*/
private Object[] filter(Object parentElementOrTreePath, Object[] elements) {
ViewerFilter[] filters = getFilters();
if (filters != null) {
ArrayList filtered = new ArrayList(elements.length);
for (int i = 0; i < elements.length; i++) {
boolean add = true;
for (int j = 0; j < filters.length; j++) {
add = filters[j].select(this, parentElementOrTreePath,
elements[i]);
if (!add) {
break;
}
}
if (add) {
filtered.add(elements[i]);
}
}
return filtered.toArray();
}
return elements;
}
/**
* Create the new elements in the parent widget. If the child already exists
* do nothing.
*
* @param widget
* @param elements
* Sorted list of elements to add.
*/
private void createAddedElements(Widget widget, Object[] elements) {
if (elements.length == 1) {
if (equals(elements[0], widget.getData())) {
return;
}
}
ViewerComparator comparator = getComparator();
TreePath parentPath = internalGetSorterParentPath(widget, comparator);
Item[] items = getChildren(widget);
// Optimize for the empty case
if (items.length == 0) {
for (int i = 0; i < elements.length; i++) {
createTreeItem(widget, elements[i], -1);
}
return;
}
// Optimize for no comparator
if (comparator == null) {
for (int i = 0; i < elements.length; i++) {
Object element = elements[i];
if (itemExists(items, element)) {
internalRefresh(element);
} else {
createTreeItem(widget, element, -1);
}
}
return;
}
// As the items are sorted already we optimize for a
// start position. This is the insertion position relative to the
// original item array.
int indexInItems = 0;
// Count of elements we have added. See bug 205700 for why this is needed.
int newItems = 0;
elementloop: for (int i = 0; i < elements.length; i++) {
Object element = elements[i];
// update the index relative to the original item array
indexInItems = insertionPosition(items, comparator,
indexInItems, element, parentPath);
if (indexInItems == items.length) {
createTreeItem(widget, element, -1);
newItems++;
} else {
// Search for an item for the element. The comparator might
// regard elements as equal when they are not.
// Use a separate index variable to search within the existing
// elements that compare equally, see
// TreeViewerTestBug205700.testAddEquallySortedElements.
int insertionIndexInItems = indexInItems;
while( insertionIndexInItems < items.length
&& internalCompare(comparator, parentPath, element,
items[insertionIndexInItems].getData()) == 0) {
// As we cannot assume the sorter is consistent with
// equals() - therefore we can
// just check against the item prior to this index (if
// any)
if (items[insertionIndexInItems].getData().equals(element)) {
// Found the item for the element.
// Refresh the element in case it has new children.
internalRefresh(element);
// Do not create a new item - continue with the next element.
continue elementloop;
}
insertionIndexInItems++;
}
// Did we get to the end?
if (insertionIndexInItems == items.length) {
createTreeItem(widget, element, -1);
newItems++;
} else {
// InsertionIndexInItems is the index in the original array. We
// need to correct by the number of new items we have
// created. See bug 205700.
createTreeItem(widget, element, insertionIndexInItems + newItems);
newItems++;
}
}
}
}
/**
* See if element is the data of one of the elements in items.
*
* @param items
* @param element
* @return true if the element matches.
*/
private boolean itemExists(Item[] items, Object element) {
if (usingElementMap()) {
Widget[] existingItems = findItems(element);
// optimization for two common cases
if (existingItems.length == 0) {
return false;
} else if (existingItems.length == 1) {
if (items.length > 0 && existingItems[0] instanceof Item) {
Item existingItem = (Item) existingItems[0];
return getParentItem(existingItem) == getParentItem(items[0]);
}
}
}
for (int i = 0; i < items.length; i++) {
if (items[i].getData().equals(element)) {
return true;
}
}
return false;
}
/**
* Returns the index where the item should be inserted. It uses sorter to
* determine the correct position, if sorter is not assigned, returns the
* index of the element after the last.
*
* @param items
* the items to search
* @param comparator
* The comparator to use.
* @param lastInsertion
* the start index to start search for position from this allows
* optimizing search for multiple elements that are sorted
* themselves.
* @param element
* element to find position for.
* @param parentPath
* the tree path for the element's parent or null
* if the element is a root element or the sorter is not a
* {@link TreePathViewerSorter}
* @return the index to use when inserting the element.
*
*/
private int insertionPosition(Item[] items, ViewerComparator comparator,
int lastInsertion, Object element, TreePath parentPath) {
int size = items.length;
if (comparator == null) {
return size;
}
int min = lastInsertion, max = size - 1;
while (min <= max) {
int mid = (min + max) / 2;
Object data = items[mid].getData();
int compare = internalCompare(comparator, parentPath, data, element);
if (compare == 0) {
return mid;// Return if we already match
}
if (compare < 0) {
min = mid + 1;
} else {
max = mid - 1;
}
}
return min;
}
/**
* Returns the index where the item should be inserted. It uses sorter to
* determine the correct position, if sorter is not assigned, returns the
* index of the element after the last.
*
* @param parent
* The parent widget
* @param sorter
* The sorter to use.
* @param startIndex
* the start index to start search for position from this allows
* optimizing search for multiple elements that are sorted
* themselves.
* @param element
* element to find position for.
* @param currentSize
* the current size of the collection
* @return the index to use when inserting the element.
*
*/
/**
* Returns the index where the item should be inserted.
*
* @param parent
* The parent widget the element will be inserted into.
* @param element
* The element to insert.
* @return the index of the element
*/
protected int indexForElement(Widget parent, Object element) {
ViewerComparator comparator = getComparator();
TreePath parentPath = internalGetSorterParentPath(parent, comparator);
Item[] items = getChildren(parent);
int count = items.length;
if (comparator == null) {
return count;
}
int min = 0, max = count - 1;
while (min <= max) {
int mid = (min + max) / 2;
Object data = items[mid].getData();
int compare = internalCompare(comparator, parentPath, data, element);
if (compare == 0) {
// find first item > element
while (compare == 0) {
++mid;
if (mid >= count) {
break;
}
data = items[mid].getData();
compare = internalCompare(comparator, parentPath, data,
element);
}
return mid;
}
if (compare < 0) {
min = mid + 1;
} else {
max = mid - 1;
}
}
return min;
}
/**
* Return the tree path that should be used as the parent path for the given
* widget and sorter. A null is returned if either the sorter
* is not a {@link TreePathViewerSorter} or if the parent widget is not an
* {@link Item} (i.e. is the root of the tree).
*
* @param parent
* the parent widget
* @param comparator
* the sorter
* @return the tree path that should be used as the parent path for the
* given widget and sorter
*/
private TreePath internalGetSorterParentPath(Widget parent,
ViewerComparator comparator) {
TreePath path;
if (comparator instanceof TreePathViewerSorter
&& parent instanceof Item) {
Item item = (Item) parent;
path = getTreePathFromItem(item);
} else {
path = null;
}
return path;
}
/**
* Compare the two elements using the given sorter. If the sorter is a
* {@link TreePathViewerSorter}, the provided tree path will be used. If
* the tree path is null and the sorter is a tree path sorter, then the
* elements are root elements
*
* @param comparator
* the sorter
* @param parentPath
* the path of the elements' parent
* @param e1
* the first element
* @param e2
* the second element
* @return the result of comparing the two elements
*/
private int internalCompare(ViewerComparator comparator,
TreePath parentPath, Object e1, Object e2) {
if (comparator instanceof TreePathViewerSorter) {
TreePathViewerSorter tpvs = (TreePathViewerSorter) comparator;
return tpvs.compare(this, parentPath, e1, e2);
}
return comparator.compare(this, e1, e2);
}
/*
* (non-Javadoc)
*
* @see org.eclipse.jface.viewers.StructuredViewer#getSortedChildren(java.lang.Object)
*/
protected Object[] getSortedChildren(Object parentElementOrTreePath) {
Object[] result = getFilteredChildren(parentElementOrTreePath);
ViewerComparator comparator = getComparator();
if (parentElementOrTreePath != null
&& comparator instanceof TreePathViewerSorter) {
TreePathViewerSorter tpvs = (TreePathViewerSorter) comparator;
// be sure we're not modifying the original array from the model
result = (Object[]) result.clone();
TreePath path = null;
if (parentElementOrTreePath instanceof TreePath) {
path = (TreePath) parentElementOrTreePath;
} else {
Object parent = parentElementOrTreePath;
Widget w = internalGetWidgetToSelect(parent);
if (w != null) {
path = internalGetSorterParentPath(w, comparator);
}
}
tpvs.sort(this, path, result);
} else if (comparator != null) {
// be sure we're not modifying the original array from the model
result = (Object[]) result.clone();
comparator.sort(this, result);
}
return result;
}
/**
* Adds the given child element to this viewer as a child of the given
* parent element. If this viewer does not have a sorter, the element is
* added at the end of the parent's list of children; otherwise, the element
* is inserted at the appropriate position.
*
* This method should be called (by the content provider) when a single
* element has been added to the model, in order to cause the viewer to
* accurately reflect the model. This method only affects the viewer, not
* the model. Note that there is another method for efficiently processing
* the simultaneous addition of multiple elements.
*
*
* @param parentElementOrTreePath
* the parent element or path
* @param childElement
* the child element
*/
public void add(Object parentElementOrTreePath, Object childElement) {
add(parentElementOrTreePath, new Object[] { childElement });
}
/**
* Adds the given SWT selection listener to the given SWT control.
*
* @param control
* the SWT control
* @param listener
* the SWT selection listener
* @deprecated
*/
protected void addSelectionListener(Control control,
SelectionListener listener) {
// do nothing
}
/**
* Adds a listener for expand and collapse events in this viewer. Has no
* effect if an identical listener is already registered.
*
* @param listener
* a tree viewer listener
*/
public void addTreeListener(ITreeViewerListener listener) {
treeListeners.add(listener);
}
/**
* Adds the given SWT tree listener to the given SWT control.
*
* @param control
* the SWT control
* @param listener
* the SWT tree listener
*/
protected abstract void addTreeListener(Control control,
TreeListener listener);
/*
* (non-Javadoc)
*
* @see StructuredViewer#associate(Object, Item)
*/
protected void associate(Object element, Item item) {
Object data = item.getData();
if (data != null && data != element && equals(data, element)) {
// workaround for PR 1FV62BT
// assumption: elements are equal but not identical
// -> remove from map but don't touch children
unmapElement(data, item);
item.setData(element);
mapElement(element, item);
} else {
// recursively disassociate all
super.associate(element, item);
}
}
/**
* Collapses all nodes of the viewer's tree, starting with the root. This
* method is equivalent to collapseToLevel(ALL_LEVELS).
*/
public void collapseAll() {
Object root = getRoot();
if (root != null) {
collapseToLevel(root, ALL_LEVELS);
}
}
/**
* Collapses the subtree rooted at the given element or tree path to the
* given level.
*
* @param elementOrTreePath
* the element or tree path
* @param level
* non-negative level, or ALL_LEVELS to collapse
* all levels of the tree
*/
public void collapseToLevel(Object elementOrTreePath, int level) {
Assert.isNotNull(elementOrTreePath);
Widget w = internalGetWidgetToSelect(elementOrTreePath);
if (w != null) {
internalCollapseToLevel(w, level);
}
}
/**
* Creates all children for the given widget.
*
* The default implementation of this framework method assumes that
* widget.getData() returns the element corresponding to the
* node. Note: the node is not visually expanded! You may have to call
* parent.setExpanded(true).
*
*
* @param widget
* the widget
*/
protected void createChildren(final Widget widget) {
createChildren(widget, true);
}
/**
* Creates all children for the given widget.
*
* The default implementation of this framework method assumes that
* widget.getData() returns the element corresponding to the
* node. Note: the node is not visually expanded! You may have to call
* parent.setExpanded(true).
*
*
* @param widget
* the widget
* @param materialize
* true if children are expected to be fully materialized
*/
void createChildren(final Widget widget, boolean materialize) {
boolean oldBusy = isBusy();
setBusy(true);
try {
final Item[] tis = getChildren(widget);
if (tis != null && tis.length > 0) {
Object data = tis[0].getData();
if (data != null) {
return; // children already there!
}
}
BusyIndicator.showWhile(widget.getDisplay(), new Runnable() {
public void run() {
// fix for PR 1FW89L7:
// don't complain and remove all "dummies" ...
if (tis != null) {
for (int i = 0; i < tis.length; i++) {
if (tis[i].getData() != null) {
disassociate(tis[i]);
Assert.isTrue(tis[i].getData() == null,
"Second or later child is non -null");//$NON-NLS-1$
}
tis[i].dispose();
}
}
Object d = widget.getData();
if (d != null) {
Object parentElement = d;
Object[] children;
if (isTreePathContentProvider() && widget instanceof Item) {
TreePath path = getTreePathFromItem((Item) widget);
children = getSortedChildren(path);
} else {
children = getSortedChildren(parentElement);
}
for (int i = 0; i < children.length; i++) {
createTreeItem(widget, children[i], -1);
}
}
}
});
} finally {
setBusy(oldBusy);
}
}
/**
* Creates a single item for the given parent and synchronizes it with the
* given element.
*
* @param parent
* the parent widget
* @param element
* the element
* @param index
* if non-negative, indicates the position to insert the item
* into its parent
*/
protected void createTreeItem(Widget parent, Object element, int index) {
Item item = newItem(parent, SWT.NULL, index);
updateItem(item, element);
updatePlus(item, element);
}
/**
* The AbstractTreeViewer implementation of this method also
* recurses over children of the corresponding element.
*/
protected void disassociate(Item item) {
super.disassociate(item);
// recursively unmapping the items is only required when
// the hash map is used. In the other case disposing
// an item will recursively dispose its children.
if (usingElementMap()) {
disassociateChildren(item);
}
}
/**
* Disassociates the children of the given SWT item from their corresponding
* elements.
*
* @param item
* the widget
*/
private void disassociateChildren(Item item) {
Item[] items = getChildren(item);
for (int i = 0; i < items.length; i++) {
if (items[i].getData() != null) {
disassociate(items[i]);
}
}
}
/* (non-Javadoc) Method declared on StructuredViewer. */
protected Widget doFindInputItem(Object element) {
// compare with root
Object root = getRoot();
if (root == null) {
return null;
}
if (equals(root, element)) {
return getControl();
}
return null;
}
/* (non-Javadoc) Method declared on StructuredViewer. */
protected Widget doFindItem(Object element) {
// compare with root
Object root = getRoot();
if (root == null) {
return null;
}
Item[] items = getChildren(getControl());
if (items != null) {
for (int i = 0; i < items.length; i++) {
Widget o = internalFindItem(items[i], element);
if (o != null) {
return o;
}
}
}
return null;
}
/**
* Copies the attributes of the given element into the given SWT item.
*
* @param item
* the SWT item
* @param element
* the element
*/
protected void doUpdateItem(final Item item, Object element) {
if (item.isDisposed()) {
unmapElement(element, item);
return;
}
int columnCount = doGetColumnCount();
if (columnCount == 0)// If no columns are created then fake one
columnCount = 1;
ViewerRow viewerRowFromItem = getViewerRowFromItem(item);
boolean isVirtual = (getControl().getStyle() & SWT.VIRTUAL) != 0;
// If the control is virtual, we cannot use the cached viewer row object. See bug 188663.
if (isVirtual) {
viewerRowFromItem = (ViewerRow) viewerRowFromItem.clone();
}
for (int column = 0; column < columnCount; column++) {
ViewerColumn columnViewer = getViewerColumn(column);
ViewerCell cellToUpdate = updateCell(viewerRowFromItem, column,
element);
// If the control is virtual, we cannot use the cached cell object. See bug 188663.
if (isVirtual) {
cellToUpdate = new ViewerCell(cellToUpdate.getViewerRow(), cellToUpdate.getColumnIndex(), element);
}
columnViewer.refresh(cellToUpdate);
// clear cell (see bug 201280)
updateCell(null, 0, null);
// As it is possible for user code to run the event
// loop check here.
if (item.isDisposed()) {
unmapElement(element, item);
return;
}
}
}
/**
* Returns true if the given list and array of items refer to
* the same model elements. Order is unimportant.
*
* This method is not intended to be overridden by subclasses.
*
*
* @param items
* the list of items
* @param current
* the array of items
* @return true if the refer to the same elements,
* false otherwise
*
* @since 1.0 in TreeViewer, moved to AbstractTreeViewer in 3.3
*/
protected boolean isSameSelection(List items, Item[] current) {
// If they are not the same size then they are not equivalent
int n = items.size();
if (n != current.length) {
return false;
}
CustomHashtable itemSet = newHashtable(n * 2 + 1);
for (Iterator i = items.iterator(); i.hasNext();) {
Item item = (Item) i.next();
Object element = item.getData();
itemSet.put(element, element);
}
// Go through the items of the current collection
// If there is a mismatch return false
for (int i = 0; i < current.length; i++) {
if (current[i].getData() == null
|| !itemSet.containsKey(current[i].getData())) {
return false;
}
}
return true;
}
/* (non-Javadoc) Method declared on StructuredViewer. */
protected void doUpdateItem(Widget widget, Object element, boolean fullMap) {
boolean oldBusy = isBusy();
setBusy(true);
try {
if (widget instanceof Item) {
Item item = (Item) widget;
// ensure that back pointer is correct
if (fullMap) {
associate(element, item);
} else {
Object data = item.getData();
if (data != null) {
unmapElement(data, item);
}
item.setData(element);
mapElement(element, item);
}
// update icon and label
SafeRunnable.run(new UpdateItemSafeRunnable(item, element));
}
} finally {
setBusy(oldBusy);
}
}
/**
* Expands all nodes of the viewer's tree, starting with the root. This
* method is equivalent to expandToLevel(ALL_LEVELS).
*/
public void expandAll() {
expandToLevel(ALL_LEVELS);
}
/**
* Expands the root of the viewer's tree to the given level.
*
* @param level
* non-negative level, or ALL_LEVELS to expand all
* levels of the tree
*/
public void expandToLevel(int level) {
expandToLevel(getRoot(), level);
}
/**
* Expands all ancestors of the given element or tree path so that the given
* element becomes visible in this viewer's tree control, and then expands
* the subtree rooted at the given element to the given level.
*
* @param elementOrTreePath
* the element
* @param level
* non-negative level, or ALL_LEVELS to expand all
* levels of the tree
*/
public void expandToLevel(Object elementOrTreePath, int level) {
if (checkBusy())
return;
Widget w = internalExpand(elementOrTreePath, true);
if (w != null) {
internalExpandToLevel(w, level);
}
}
/**
* Fires a tree collapsed event. Only listeners registered at the time this
* method is called are notified.
*
* @param event
* the tree expansion event
* @see ITreeViewerListener#treeCollapsed
*/
protected void fireTreeCollapsed(final TreeExpansionEvent event) {
Object[] listeners = treeListeners.getListeners();
boolean oldBusy = isBusy();
setBusy(true);
try {
for (int i = 0; i < listeners.length; ++i) {
final ITreeViewerListener l = (ITreeViewerListener) listeners[i];
SafeRunnable.run(new SafeRunnable() {
public void run() {
l.treeCollapsed(event);
}
});
}
} finally {
setBusy(oldBusy);
}
}
/**
* Fires a tree expanded event. Only listeners registered at the time this
* method is called are notified.
*
* @param event
* the tree expansion event
* @see ITreeViewerListener#treeExpanded
*/
protected void fireTreeExpanded(final TreeExpansionEvent event) {
Object[] listeners = treeListeners.getListeners();
boolean oldBusy = isBusy();
setBusy(true);
try {
for (int i = 0; i < listeners.length; ++i) {
final ITreeViewerListener l = (ITreeViewerListener) listeners[i];
SafeRunnable.run(new SafeRunnable() {
public void run() {
l.treeExpanded(event);
}
});
}
} finally {
setBusy(oldBusy);
}
}
/**
* Returns the auto-expand level.
*
* @return non-negative level, or ALL_LEVELS if all levels of
* the tree are expanded automatically
* @see #setAutoExpandLevel
*/
public int getAutoExpandLevel() {
return expandToLevel;
}
/**
* Returns the SWT child items for the given SWT widget.
*
* @param widget
* the widget
* @return the child items
*/
protected abstract Item[] getChildren(Widget widget);
/**
* Get the child for the widget at index. Note that the default
* implementation is not very efficient and should be overridden if this
* class is implemented.
*
* @param widget
* the widget to check
* @param index
* the index of the widget
* @return Item or null if widget is not a type that can
* contain items.
*
* @throws ArrayIndexOutOfBoundsException
* if the index is not valid.
* @since 1.0
*/
protected Item getChild(Widget widget, int index) {
return getChildren(widget)[index];
}
/**
* Returns whether the given SWT item is expanded or collapsed.
*
* @param item
* the item
* @return true if the item is considered expanded and
* false if collapsed
*/
protected abstract boolean getExpanded(Item item);
/**
* Returns a list of elements corresponding to expanded nodes in this
* viewer's tree, including currently hidden ones that are marked as
* expanded but are under a collapsed ancestor.
*
* This method is typically used when preserving the interesting state of a
* viewer; setExpandedElements is used during the restore.
*
*
* @return the array of expanded elements
* @see #setExpandedElements
*/
public Object[] getExpandedElements() {
ArrayList items = new ArrayList();
internalCollectExpandedItems(items, getControl());
ArrayList result = new ArrayList(items.size());
for (Iterator it = items.iterator(); it.hasNext();) {
Item item = (Item) it.next();
Object data = item.getData();
if (data != null) {
result.add(data);
}
}
return result.toArray();
}
/**
* Returns whether the node corresponding to the given element or tree path
* is expanded or collapsed.
*
* @param elementOrTreePath
* the element
* @return true if the node is expanded, and
* false if collapsed
*/
public boolean getExpandedState(Object elementOrTreePath) {
Assert.isNotNull(elementOrTreePath);
Widget item = internalGetWidgetToSelect(elementOrTreePath);
if (item instanceof Item) {
return getExpanded((Item) item);
}
return false;
}
/**
* Returns the number of child items of the given SWT control.
*
* @param control
* the control
* @return the number of children
*/
protected abstract int getItemCount(Control control);
/**
* Returns the number of child items of the given SWT item.
*
* @param item
* the item
* @return the number of children
*/
protected abstract int getItemCount(Item item);
/**
* Returns the child items of the given SWT item.
*
* @param item
* the item
* @return the child items
*/
protected abstract Item[] getItems(Item item);
/**
* Returns the item after the given item in the tree, or null
* if there is no next item.
*
* @param item
* the item
* @param includeChildren
* true if the children are considered in
* determining which item is next, and false if
* subtrees are ignored
* @return the next item, or null if none
*/
protected Item getNextItem(Item item, boolean includeChildren) {
if (item == null) {
return null;
}
if (includeChildren && getExpanded(item)) {
Item[] children = getItems(item);
if (children != null && children.length > 0) {
return children[0];
}
}
// next item is either next sibling or next sibling of first
// parent that has a next sibling.
Item parent = getParentItem(item);
if (parent == null) {
return null;
}
Item[] siblings = getItems(parent);
if (siblings != null) {
if (siblings.length <= 1) {
return getNextItem(parent, false);
}
for (int i = 0; i < siblings.length; i++) {
if (siblings[i] == item && i < (siblings.length - 1)) {
return siblings[i + 1];
}
}
}
return getNextItem(parent, false);
}
/**
* Returns the parent item of the given item in the tree, or
* null if there is no parent item.
*
* @param item
* the item
* @return the parent item, or null if none
*/
protected abstract Item getParentItem(Item item);
/**
* Returns the item before the given item in the tree, or null
* if there is no previous item.
*
* @param item
* the item
* @return the previous item, or null if none
*/
protected Item getPreviousItem(Item item) {
// previous item is either right-most visible descendent of previous
// sibling or parent
Item parent = getParentItem(item);
if (parent == null) {
return null;
}
Item[] siblings = getItems(parent);
if (siblings.length == 0 || siblings[0] == item) {
return parent;
}
Item previous = siblings[0];
for (int i = 1; i < siblings.length; i++) {
if (siblings[i] == item) {
return rightMostVisibleDescendent(previous);
}
previous = siblings[i];
}
return null;
}
/* (non-Javadoc) Method declared on StructuredViewer. */
protected Object[] getRawChildren(Object parentElementOrTreePath) {
boolean oldBusy = isBusy();
setBusy(true);
try {
Object parent;
TreePath path;
if (parentElementOrTreePath instanceof TreePath) {
path = (TreePath) parentElementOrTreePath;
parent = path.getLastSegment();
} else {
parent = parentElementOrTreePath;
path = null;
}
if (parent != null) {
if (equals(parent, getRoot())) {
return super.getRawChildren(parent);
}
IContentProvider cp = getContentProvider();
if (cp instanceof ITreePathContentProvider) {
ITreePathContentProvider tpcp = (ITreePathContentProvider) cp;
if (path == null) {
// A path was not provided so try and find one
Widget w = findItem(parent);
if (w instanceof Item) {
Item item = (Item) w;
path = getTreePathFromItem(item);
}
if (path == null) {
path = new TreePath(new Object[] { parent });
}
}
Object[] result = tpcp.getChildren(path);
if (result != null) {
return result;
}
} else if (cp instanceof ITreeContentProvider) {
ITreeContentProvider tcp = (ITreeContentProvider) cp;
Object[] result = tcp.getChildren(parent);
if (result != null) {
return result;
}
}
}
return new Object[0];
} finally {
setBusy(oldBusy);
}
}
/**
* Returns all selected items for the given SWT control.
*
* @param control
* the control
* @return the list of selected items
*/
protected abstract Item[] getSelection(Control control);
/*
* (non-Javadoc)
*
* @see org.eclipse.jface.viewers.StructuredViewer#getSelectionFromWidget()
*/
protected List getSelectionFromWidget() {
Widget[] items = getSelection(getControl());
ArrayList list = new ArrayList(items.length);
for (int i = 0; i < items.length; i++) {
Widget item = items[i];
Object e = item.getData();
if (e != null) {
list.add(e);
}
}
return list;
}
/*
* Overridden in AbstractTreeViewer to fix bug 108102 (code copied from
* StructuredViewer to avoid introducing new API) (non-Javadoc)
*
* @see org.eclipse.jface.viewers.StructuredViewer#handleDoubleSelect(org.eclipse.swt.events.SelectionEvent)
*/
protected void handleDoubleSelect(SelectionEvent event) {
// handle case where an earlier selection listener disposed the control.
Control control = getControl();
if (control != null && !control.isDisposed()) {
// If the double-clicked element can be obtained from the event, use
// it
// otherwise get it from the control. Some controls like List do
// not have the notion of item.
// For details, see bug 90161 [Navigator] DefaultSelecting folders
// shouldn't always expand first one
ISelection selection;
// RAP [if] Add a check for disposed item - see bug 413920
if (event.item != null && !event.item.isDisposed() && event.item.getData() != null) {
// if (event.item != null && event.item.getData() != null) {
// changes to fix bug 108102 follow
TreePath treePath = getTreePathFromItem((Item) event.item);
selection = new TreeSelection(treePath);
// end of changes
} else {
selection = getSelection();
updateSelection(selection);
}
fireDoubleClick(new DoubleClickEvent(this, selection));
}
}
/**
* Handles a tree collapse event from the SWT widget.
*
* @param event
* the SWT tree event
*/
protected void handleTreeCollapse(TreeEvent event) {
if (event.item.getData() != null) {
fireTreeCollapsed(new TreeExpansionEvent(this, event.item.getData()));
}
}
/**
* Handles a tree expand event from the SWT widget.
*
* @param event
* the SWT tree event
*/
protected void handleTreeExpand(TreeEvent event) {
createChildren(event.item);
if (event.item.getData() != null) {
fireTreeExpanded(new TreeExpansionEvent(this, event.item.getData()));
}
}
/* (non-Javadoc) Method declared on Viewer. */
protected void hookControl(Control control) {
super.hookControl(control);
addTreeListener(control, new TreeListener() {
public void treeExpanded(TreeEvent event) {
handleTreeExpand(event);
}
public void treeCollapsed(TreeEvent event) {
handleTreeCollapse(event);
}
});
}
/*
* (non-Javadoc) Method declared on StructuredViewer. Builds the initial
* tree and handles the automatic expand feature.
*/
protected void inputChanged(Object input, Object oldInput) {
preservingSelection(new Runnable() {
public void run() {
Control tree = getControl();
tree.setRedraw(false);
try {
removeAll(tree);
tree.setData(getRoot());
internalInitializeTree(tree);
} finally {
tree.setRedraw(true);
}
}
});
}
/**
* Initializes the tree with root items, expanding to the appropriate
* level if necessary.
*
* @param tree the tree control
* @since 1.0
*/
protected void internalInitializeTree(Control tree) {
createChildren(tree);
internalExpandToLevel(tree, expandToLevel);
}
/**
* Recursively collapses the subtree rooted at the given widget to the given
* level.
*
*
* Note that the default implementation of this method does not call
* setRedraw.
*
* @param widget
* the widget
* @param level
* non-negative level, or ALL_LEVELS to collapse
* all levels of the tree
*/
protected void internalCollapseToLevel(Widget widget, int level) {
if (level == ALL_LEVELS || level > 0) {
if (widget instanceof Item) {
Item item = (Item) widget;
setExpanded(item, false);
Object element = item.getData();
if (element != null && level == ALL_LEVELS) {
if (optionallyPruneChildren(item, element)) {
return;
}
}
}
if (level == ALL_LEVELS || level > 1) {
Item[] children = getChildren(widget);
if (children != null) {
int nextLevel = (level == ALL_LEVELS ? ALL_LEVELS
: level - 1);
for (int i = 0; i < children.length; i++) {
internalCollapseToLevel(children[i], nextLevel);
}
}
}
}
}
/**
* Recursively collects all expanded items from the given widget.
*
* @param result
* a list (element type: Item) into which to
* collect the elements
* @param widget
* the widget
*/
private void internalCollectExpandedItems(List result, Widget widget) {
Item[] items = getChildren(widget);
for (int i = 0; i < items.length; i++) {
Item item = items[i];
// Disregard dummy nodes (see bug 287765)
if (item.getData() != null) {
if (getExpanded(item)) {
result.add(item);
}
internalCollectExpandedItems(result, item);
}
}
}
/**
* Tries to create a path of tree items for the given element or tree path.
* This method recursively walks up towards the root of the tree and in the
* case of an element (rather than a tree path) assumes that
* getParent returns the correct parent of an element.
*
* @param elementOrPath
* the element
* @param expand
* true if all nodes on the path should be
* expanded, and false otherwise
* @return Widget
*/
protected Widget internalExpand(Object elementOrPath, boolean expand) {
if (elementOrPath == null) {
return null;
}
Widget w = internalGetWidgetToSelect(elementOrPath);
if (w == null) {
if (equals(elementOrPath, getRoot())) { // stop at root
return null;
}
// my parent has to create me
Object parent = getParentElement(elementOrPath);
if (parent != null) {
Widget pw = internalExpand(parent, false);
if (pw != null) {
// let my parent create me
createChildren(pw);
Object element = internalToElement(elementOrPath);
w = internalFindChild(pw, element);
if (expand && pw instanceof Item) {
// expand parent items top-down
Item item = (Item) pw;
LinkedList toExpandList = new LinkedList();
while (item != null && !getExpanded(item)) {
toExpandList.addFirst(item);
item = getParentItem(item);
}
for (Iterator it = toExpandList.iterator(); it
.hasNext();) {
Item toExpand = (Item) it.next();
setExpanded(toExpand, true);
}
}
}
}
}
return w;
}
/**
* If the argument is a tree path, returns its last segment, otherwise
* return the argument
*
* @param elementOrPath
* an element or a tree path
* @return the element, or the last segment of the tree path
*/
private Object internalToElement(Object elementOrPath) {
if (elementOrPath instanceof TreePath) {
return ((TreePath) elementOrPath).getLastSegment();
}
return elementOrPath;
}
/**
* This method takes a tree path or an element. If the argument is not a
* tree path, returns the parent of the given element or null
* if the parent is not known. If the argument is a tree path with more than
* one segment, returns its parent tree path, otherwise returns
* null.
*
* @param elementOrTreePath
* @return the parent element, or parent path, or null
*
* @since 1.0
*/
protected Object getParentElement(Object elementOrTreePath) {
if (elementOrTreePath instanceof TreePath) {
TreePath treePath = (TreePath) elementOrTreePath;
return (treePath).getParentPath();
}
IContentProvider cp = getContentProvider();
if (cp instanceof ITreePathContentProvider) {
ITreePathContentProvider tpcp = (ITreePathContentProvider) cp;
TreePath[] paths = tpcp.getParents(elementOrTreePath);
if (paths.length > 0) {
if (paths[0].getSegmentCount() == 0) {
return getRoot();
}
return paths[0].getLastSegment();
}
}
if (cp instanceof ITreeContentProvider) {
ITreeContentProvider tcp = (ITreeContentProvider) cp;
return tcp.getParent(elementOrTreePath);
}
return null;
}
/**
* Returns the widget to be selected for the given element or tree path.
*
* @param elementOrTreePath
* the element or tree path to select
* @return the widget to be selected, or null if not found
*
* @since 1.0
*/
protected Widget internalGetWidgetToSelect(Object elementOrTreePath) {
if (elementOrTreePath instanceof TreePath) {
TreePath treePath = (TreePath) elementOrTreePath;
if (treePath.getSegmentCount() == 0) {
return getControl();
}
Widget[] candidates = findItems(treePath.getLastSegment());
for (int i = 0; i < candidates.length; i++) {
Widget candidate = candidates[i];
if (!(candidate instanceof Item)) {
continue;
}
if (treePath.equals(getTreePathFromItem((Item) candidate),
getComparer())) {
return candidate;
}
}
return null;
}
return findItem(elementOrTreePath);
}
/**
* Recursively expands the subtree rooted at the given widget to the given
* level.
*
*
* Note that the default implementation of this method does not call
* setRedraw.
*
* @param widget
* the widget
* @param level
* non-negative level, or ALL_LEVELS to collapse
* all levels of the tree
*/
protected void internalExpandToLevel(Widget widget, int level) {
if (level == ALL_LEVELS || level > 0) {
if (widget instanceof Item && widget.getData() != null
&& !isExpandable((Item) widget, null, widget.getData())) {
return;
}
createChildren(widget, false);
if (widget instanceof Item) {
setExpanded((Item) widget, true);
}
if (level == ALL_LEVELS || level > 1) {
Item[] children = getChildren(widget);
if (children != null) {
int newLevel = (level == ALL_LEVELS ? ALL_LEVELS
: level - 1);
for (int i = 0; i < children.length; i++) {
internalExpandToLevel(children[i], newLevel);
}
}
}
}
}
/**
* Non-recursively tries to find the given element as a child of the given
* parent (item or tree).
*
* @param parent
* the parent item
* @param element
* the element
* @return Widget
*/
private Widget internalFindChild(Widget parent, Object element) {
Item[] items = getChildren(parent);
for (int i = 0; i < items.length; i++) {
Item item = items[i];
Object data = item.getData();
if (data != null && equals(data, element)) {
return item;
}
}
return null;
}
/**
* Recursively tries to find the given element.
*
* @param parent
* the parent item
* @param element
* the element
* @return Widget
*/
private Widget internalFindItem(Item parent, Object element) {
// compare with node
Object data = parent.getData();
if (data != null) {
if (equals(data, element)) {
return parent;
}
}
// recurse over children
Item[] items = getChildren(parent);
for (int i = 0; i < items.length; i++) {
Item item = items[i];
Widget o = internalFindItem(item, element);
if (o != null) {
return o;
}
}
return null;
}
/* (non-Javadoc) Method declared on StructuredViewer. */
protected void internalRefresh(Object element) {
internalRefresh(element, true);
}
/* (non-Javadoc) Method declared on StructuredViewer. */
protected void internalRefresh(Object element, boolean updateLabels) {
// If element is null, do a full refresh.
if (element == null) {
internalRefresh(getControl(), getRoot(), true, updateLabels);
return;
}
Widget[] items = findItems(element);
if (items.length != 0) {
for (int i = 0; i < items.length; i++) {
// pick up structure changes too
internalRefresh(items[i], element, true, updateLabels);
}
}
}
/**
* Refreshes the tree starting at the given widget.
*
* EXPERIMENTAL. Not to be used except by JDT. This method was added to
* support JDT's explorations into grouping by working sets. This method
* cannot be removed without breaking binary backwards compatibility, but
* should not be called by clients.
*
*
* @param widget
* the widget
* @param element
* the element
* @param doStruct
* true if structural changes are to be picked up,
* and false if only label provider changes are of
* interest
* @param updateLabels
* true to update labels for existing elements,
* false to only update labels as needed, assuming
* that labels for existing elements are unchanged.
* @since 1.0
*/
protected void internalRefresh(Widget widget, Object element,
boolean doStruct, boolean updateLabels) {
if (widget instanceof Item) {
if (doStruct) {
updatePlus((Item) widget, element);
}
if (updateLabels || !equals(element, widget.getData())) {
doUpdateItem(widget, element, true);
} else {
associate(element, (Item) widget);
}
}
if (doStruct) {
internalRefreshStruct(widget, element, updateLabels);
} else {
Item[] children = getChildren(widget);
if (children != null) {
for (int i = 0; i < children.length; i++) {
Widget item = children[i];
Object data = item.getData();
if (data != null) {
internalRefresh(item, data, doStruct, updateLabels);
}
}
}
}
}
/**
* Update the structure and recurse. Items are updated in updateChildren, as
* needed.
*
* @param widget
* @param element
* @param updateLabels
*/
/* package */void internalRefreshStruct(Widget widget, Object element,
boolean updateLabels) {
updateChildren(widget, element, null, updateLabels);
Item[] children = getChildren(widget);
if (children != null) {
for (int i = 0; i < children.length; i++) {
Widget item = children[i];
Object data = item.getData();
if (data != null) {
internalRefreshStruct(item, data, updateLabels);
}
}
}
}
/**
* Removes the given elements from this viewer.
*
* EXPERIMENTAL. Not to be used except by JDT. This method was added to
* support JDT's explorations into grouping by working sets. This method
* cannot be removed without breaking binary backwards compatibility, but
* should not be called by clients.
*
*
* @param elementsOrPaths
* the elements or element paths to remove
* @since 1.0
*/
protected void internalRemove(Object[] elementsOrPaths) {
Object input = getInput();
for (int i = 0; i < elementsOrPaths.length; ++i) {
Object element = elementsOrPaths[i];
if (equals(element, input)) {
setInput(null);
return;
}
Widget[] childItems = internalFindItems(element);
if (childItems.length > 0) {
for (int j = 0; j < childItems.length; j++) {
Widget childItem = childItems[j];
if (childItem instanceof Item) {
disassociate((Item) childItem);
childItem.dispose();
}
}
} else {
// see https://bugs.eclipse.org/bugs/show_bug.cgi?id=210747
Object parent = getParentElement(element);
if (parent != null
&& !equals(parent, getRoot())
&& !(parent instanceof TreePath && ((TreePath) parent)
.getSegmentCount() == 0)) {
Widget[] parentItems = internalFindItems(parent);
for (int j = 0; j < parentItems.length; j++) {
Widget parentItem = parentItems[j];
if (parentItem instanceof Item) {
updatePlus((Item) parentItem, parent);
}
}
}
}
}
}
/**
* Removes the given elements from this viewer, whenever those elements
* appear as children of the given parent.
*
* @param parent the parent element
* @param elements
* the elements to remove
* @since 1.0
*/
protected void internalRemove(Object parent, Object[] elements) {
CustomHashtable toRemove = new CustomHashtable(getComparer());
for (int i = 0; i < elements.length; i++) {
toRemove.put(elements[i], elements[i]);
}
// Find each place the parent appears in the tree
Widget[] parentItemArray = findItems(parent);
for (int i = 0; i < parentItemArray.length; i++) {
Widget parentItem = parentItemArray[i];
// May happen if parent element is a descendent of of a previously
// removed element
if (parentItem.isDisposed())
continue;
// Iterate over the child items and remove each one
Item[] children = getChildren(parentItem);
if (children.length == 1 && children[0].getData() == null &&
parentItem instanceof Item) { // dummy node
// Remove plus if parent element has no children
updatePlus((Item) parentItem, parent);
} else {
for (int j = 0; j < children.length; j++) {
Item child = children[j];
Object data = child.getData();
if (data != null && toRemove.containsKey(data)) {
disassociate(child);
child.dispose();
}
}
}
}
}
/**
* Sets the expanded state of all items to correspond to the given set of
* expanded elements.
*
* @param expandedElements
* the set (element type: Object) of elements
* which are expanded
* @param widget
* the widget
*/
private void internalSetExpanded(CustomHashtable expandedElements,
Widget widget) {
Item[] items = getChildren(widget);
for (int i = 0; i < items.length; i++) {
Item item = items[i];
Object data = item.getData();
if (data != null) {
// remove the element to avoid an infinite loop
// if the same element appears on a child item
boolean expanded = expandedElements.remove(data) != null;
if (expanded != getExpanded(item)) {
if (expanded) {
createChildren(item);
}
setExpanded(item, expanded);
}
}
if (expandedElements.size() > 0) {
internalSetExpanded(expandedElements, item);
}
}
}
/**
* Sets the expanded state of all items to correspond to the given set of
* expanded tree paths.
*
* @param expandedTreePaths
* the set (element type: TreePath) of elements
* which are expanded
* @param widget
* the widget
*/
private void internalSetExpandedTreePaths(
CustomHashtable expandedTreePaths, Widget widget,
TreePath currentPath) {
Item[] items = getChildren(widget);
for (int i = 0; i < items.length; i++) {
Item item = items[i];
Object data = item.getData();
TreePath childPath = data == null ? null : currentPath
.createChildPath(data);
if (data != null && childPath != null) {
// remove the element to avoid an infinite loop
// if the same element appears on a child item
boolean expanded = expandedTreePaths.remove(childPath) != null;
if (expanded != getExpanded(item)) {
if (expanded) {
createChildren(item);
}
setExpanded(item, expanded);
}
}
internalSetExpandedTreePaths(expandedTreePaths, item, childPath);
}
}
/**
* Return whether the tree node representing the given element or path can
* be expanded. Clients should query expandability by path if the viewer's
* content provider is an {@link ITreePathContentProvider}.
*
* The default implementation of this framework method calls
* hasChildren on this viewer's content provider. It may be
* overridden if necessary.
*
*
* @param elementOrTreePath
* the element or path
* @return true if the tree node representing the given
* element can be expanded, or false if not
*/
public boolean isExpandable(Object elementOrTreePath) {
Object element;
TreePath path;
if (elementOrTreePath instanceof TreePath) {
path = (TreePath) elementOrTreePath;
element = path.getLastSegment();
} else {
element = elementOrTreePath;
path = null;
}
IContentProvider cp = getContentProvider();
if (cp instanceof ITreePathContentProvider) {
ITreePathContentProvider tpcp = (ITreePathContentProvider) cp;
if (path == null) {
// A path was not provided so try and find one
Widget w = findItem(element);
if (w instanceof Item) {
Item item = (Item) w;
path = getTreePathFromItem(item);
}
if (path == null) {
path = new TreePath(new Object[] { element });
}
}
return tpcp.hasChildren(path);
}
if (cp instanceof ITreeContentProvider) {
ITreeContentProvider tcp = (ITreeContentProvider) cp;
return tcp.hasChildren(element);
}
return false;
}
/**
* Return whether the given element is expandable.
*
* @param item
* the tree item for the element
* @param parentPath
* the parent path if it is known or null if it
* needs to be determines
* @param element
* the element
* @return whether the given element is expandable
*/
private boolean isExpandable(Item item, TreePath parentPath, Object element) {
Object elementOrTreePath = element;
if (isTreePathContentProvider()) {
if (parentPath != null) {
elementOrTreePath = parentPath.createChildPath(element);
} else {
elementOrTreePath = getTreePathFromItem(item);
}
}
return isExpandable(elementOrTreePath);
}
/* (non-Javadoc) Method declared on Viewer. */
protected void labelProviderChanged() {
// we have to walk the (visible) tree and update every item
Control tree = getControl();
tree.setRedraw(false);
// don't pick up structure changes, but do force label updates
internalRefresh(tree, getRoot(), false, true);
tree.setRedraw(true);
}
/**
* Creates a new item.
*
* @param parent
* the parent widget
* @param style
* SWT style bits
* @param index
* if non-negative, indicates the position to insert the item
* into its parent
* @return the newly-created item
*/
protected abstract Item newItem(Widget parent, int style, int index);
/**
* Removes the given elements from this viewer. The selection is updated if
* required.
*
* This method should be called (by the content provider) when elements have
* been removed from the model, in order to cause the viewer to accurately
* reflect the model. This method only affects the viewer, not the model.
*
*
* @param elementsOrTreePaths
* the elements to remove
*/
public void remove(final Object[] elementsOrTreePaths) {
assertElementsNotNull(elementsOrTreePaths);
if (elementsOrTreePaths.length == 0) {
return;
}
if (checkBusy())
return;
preservingSelection(new Runnable() {
public void run() {
internalRemove(elementsOrTreePaths);
}
});
}
/**
* Removes the given elements from this viewer whenever they appear as
* children of the given parent element. If the given elements also appear
* as children of some other parent, the other parent will remain unchanged.
* The selection is updated if required.
*
* This method should be called (by the content provider) when elements have
* been removed from the model, in order to cause the viewer to accurately
* reflect the model. This method only affects the viewer, not the model.
*
*
* @param parent
* the parent of the elements to remove
* @param elements
* the elements to remove
*
* @since 1.0
*/
public void remove(final Object parent, final Object[] elements) {
assertElementsNotNull(elements);
if (elements.length == 0) {
return;
}
if (checkBusy())
return;
preservingSelection(new Runnable() {
public void run() {
internalRemove(parent, elements);
}
});
}
/**
* Removes the given element from the viewer. The selection is updated if
* necessary.
*
* This method should be called (by the content provider) when a single
* element has been removed from the model, in order to cause the viewer to
* accurately reflect the model. This method only affects the viewer, not
* the model. Note that there is another method for efficiently processing
* the simultaneous removal of multiple elements.
*
*
* @param elementsOrTreePaths
* the element
*/
public void remove(Object elementsOrTreePaths) {
remove(new Object[] { elementsOrTreePaths });
}
/**
* Removes all items from the given control.
*
* @param control
* the control
*/
protected abstract void removeAll(Control control);
/**
* Removes a listener for expand and collapse events in this viewer. Has no
* effect if an identical listener is not registered.
*
* @param listener
* a tree viewer listener
*/
public void removeTreeListener(ITreeViewerListener listener) {
treeListeners.remove(listener);
}
/**
* This implementation of reveal() reveals the given element or tree path.
*/
public void reveal(Object elementOrTreePath) {
Assert.isNotNull(elementOrTreePath);
Widget w = internalExpand(elementOrTreePath, true);
if (w instanceof Item) {
showItem((Item) w);
}
}
/**
* Returns the rightmost visible descendent of the given item. Returns the
* item itself if it has no children.
*
* @param item
* the item to compute the descendent of
* @return the rightmost visible descendent or the item itself if it has no
* children
*/
private Item rightMostVisibleDescendent(Item item) {
Item[] children = getItems(item);
if (getExpanded(item) && children != null && children.length > 0) {
return rightMostVisibleDescendent(children[children.length - 1]);
}
return item;
}
/* (non-Javadoc) Method declared on Viewer. */
public Item scrollDown(int x, int y) {
Item current = getItem(x, y);
if (current != null) {
Item next = getNextItem(current, true);
showItem(next == null ? current : next);
return next;
}
return null;
}
/* (non-Javadoc) Method declared on Viewer. */
public Item scrollUp(int x, int y) {
Item current = getItem(x, y);
if (current != null) {
Item previous = getPreviousItem(current);
showItem(previous == null ? current : previous);
return previous;
}
return null;
}
/**
* Sets the auto-expand level to be used when the input of the viewer is set
* using {@link #setInput(Object)}. The value 0 means that there is no
* auto-expand; 1 means that the invisible root element is expanded (since
* most concrete subclasses do not show the root element, there is usually
* no practical difference between using the values 0 and 1); 2 means that
* top-level elements are expanded, but not their children; 3 means that
* top-level elements are expanded, and their children, but not
* grandchildren; and so on.
*
* The value ALL_LEVELS means that all subtrees should be
* expanded.
*
*
* Note that in previous releases, the Javadoc for this method had an off-by
* one error. See bug 177669 for details.
*
*
* @param level
* non-negative level, or ALL_LEVELS to expand all
* levels of the tree
*/
public void setAutoExpandLevel(int level) {
expandToLevel = level;
}
/**
* The AbstractTreeViewer implementation of this method
* checks to ensure that the content provider is an
* ITreeContentProvider.
*/
public void setContentProvider(IContentProvider provider) {
// the actual check is in assertContentProviderType
super.setContentProvider(provider);
}
protected void assertContentProviderType(IContentProvider provider) {
Assert.isTrue(provider instanceof ITreeContentProvider
|| provider instanceof ITreePathContentProvider);
}
/**
* Sets the expand state of the given item.
*
* @param item
* the item
* @param expand
* the expand state of the item
*/
protected abstract void setExpanded(Item item, boolean expand);
/**
* Sets which nodes are expanded in this viewer's tree. The given list
* contains the elements that are to be expanded; all other nodes are to be
* collapsed.
*
* This method is typically used when restoring the interesting state of a
* viewer captured by an earlier call to getExpandedElements.
*
*
* @param elements
* the array of expanded elements
* @see #getExpandedElements
*/
public void setExpandedElements(Object[] elements) {
assertElementsNotNull(elements);
if (checkBusy()) {
return;
}
CustomHashtable expandedElements = newHashtable(elements.length * 2 + 1);
for (int i = 0; i < elements.length; ++i) {
Object element = elements[i];
// Ensure item exists for element. This will materialize items for
// each element and their parents, if possible. This is important
// to support expanding of inner tree nodes without necessarily
// expanding their parents.
internalExpand(element, false);
expandedElements.put(element, element);
}
// this will traverse all existing items, and create children for
// elements that need to be expanded. If the tree contains multiple
// equal elements, and those are in the set of elements to be expanded,
// only the first item found for each element will be expanded.
internalSetExpanded(expandedElements, getControl());
}
/**
* Sets which nodes are expanded in this viewer's tree. The given list
* contains the tree paths that are to be expanded; all other nodes are to
* be collapsed.
*
* This method is typically used when restoring the interesting state of a
* viewer captured by an earlier call to getExpandedTreePaths.
*
*
* @param treePaths
* the array of expanded tree paths
* @see #getExpandedTreePaths()
*
* @since 1.0
*/
public void setExpandedTreePaths(TreePath[] treePaths) {
assertElementsNotNull(treePaths);
if (checkBusy())
return;
final IElementComparer comparer = getComparer();
IElementComparer treePathComparer = new IElementComparer() {
public boolean equals(Object a, Object b) {
return ((TreePath) a).equals(((TreePath) b), comparer);
}
public int hashCode(Object element) {
return ((TreePath) element).hashCode(comparer);
}
};
CustomHashtable expandedTreePaths = new CustomHashtable(
treePaths.length * 2 + 1, treePathComparer);
for (int i = 0; i < treePaths.length; ++i) {
TreePath treePath = treePaths[i];
// Ensure item exists for element. This will materialize items for
// each element and their parents, if possible. This is important
// to support expanding of inner tree nodes without necessarily
// expanding their parents.
internalExpand(treePath, false);
expandedTreePaths.put(treePath, treePath);
}
// this will traverse all existing items, and create children for
// elements that need to be expanded. If the tree contains multiple
// equal elements, and those are in the set of elements to be expanded,
// only the first item found for each element will be expanded.
internalSetExpandedTreePaths(expandedTreePaths, getControl(),
new TreePath(new Object[0]));
}
/**
* Sets whether the node corresponding to the given element or tree path is
* expanded or collapsed.
*
* @param elementOrTreePath
* the element
* @param expanded
* true if the node is expanded, and
* false if collapsed
*/
public void setExpandedState(Object elementOrTreePath, boolean expanded) {
Assert.isNotNull(elementOrTreePath);
if (checkBusy())
return;
Widget item = internalExpand(elementOrTreePath, false);
if (item instanceof Item) {
if (expanded) {
createChildren(item);
}
setExpanded((Item) item, expanded);
}
}
/**
* Sets the selection to the given list of items.
*
* @param items
* list of items (element type:
* org.eclipse.swt.widgets.Item)
*/
protected abstract void setSelection(List items);
/**
* This implementation of setSelectionToWidget accepts a list of elements or
* a list of tree paths.
*/
protected void setSelectionToWidget(List v, boolean reveal) {
if (v == null) {
setSelection(new ArrayList(0));
return;
}
int size = v.size();
List newSelection = new ArrayList(size);
for (int i = 0; i < size; ++i) {
Object elementOrTreePath = v.get(i);
// Use internalExpand since item may not yet be created. See
// 1G6B1AR.
Widget w = internalExpand(elementOrTreePath, false);
if (w instanceof Item) {
newSelection.add(w);
} else if (w == null && elementOrTreePath instanceof TreePath) {
TreePath treePath = (TreePath) elementOrTreePath;
Object element = treePath.getLastSegment();
if (element != null) {
w = internalExpand(element, false);
if (w instanceof Item) {
newSelection.add(w);
}
}
}
}
setSelection(newSelection);
// Although setting the selection in the control should reveal it,
// setSelection may be a no-op if the selection is unchanged,
// so explicitly reveal items in the selection here.
// See bug 100565 for more details.
if (reveal && newSelection.size() > 0) {
// Iterate backwards so the first item in the list
// is the one guaranteed to be visible
for (int i = (newSelection.size()-1); i >= 0; i--) {
showItem((Item) newSelection.get(i));
}
}
}
/**
* Shows the given item.
*
* @param item
* the item
*/
protected abstract void showItem(Item item);
/**
* Updates the tree items to correspond to the child elements of the given
* parent element. If null is passed for the children, this method obtains
* them (only if needed).
*
* @param widget
* the widget
* @param parent
* the parent element
* @param elementChildren
* the child elements, or null
* @deprecated this is no longer called by the framework
*/
protected void updateChildren(Widget widget, Object parent,
Object[] elementChildren) {
updateChildren(widget, parent, elementChildren, true);
}
/**
* Updates the tree items to correspond to the child elements of the given
* parent element. If null is passed for the children, this method obtains
* them (only if needed).
*
* @param widget
* the widget
* @param parent
* the parent element
* @param elementChildren
* the child elements, or null
* @param updateLabels
* true to update labels for existing elements,
* false to only update labels as needed, assuming
* that labels for existing elements are unchanged.
* @since 2.1
*/
private void updateChildren(Widget widget, Object parent,
Object[] elementChildren, boolean updateLabels) {
// optimization! prune collapsed subtrees
if (widget instanceof Item) {
Item ti = (Item) widget;
if (!getExpanded(ti)) {
if (optionallyPruneChildren(ti, parent)) {
// children were pruned, nothing left to do
return;
}
// The following code is being executed if children were not pruned.
// This is (as of 3.5) only the case for CheckboxTreeViewer.
Item[] its = getItems(ti);
if (isExpandable(ti, null, parent)) {
if (its.length == 0) {
// need dummy node
newItem(ti, SWT.NULL, -1);
return;
} else if (its.length == 1 && its[0].getData() == null) {
// dummy node exists, nothing left to do
return;
}
// else fall through to normal update code below
} else {
for (int i = 0; i < its.length; i++) {
if (its[i].getData() != null) {
disassociate(its[i]);
}
its[i].dispose();
}
// nothing left to do
return;
}
}
}
// If the children weren't passed in, get them now since they're needed
// below.
if (elementChildren == null) {
if (isTreePathContentProvider() && widget instanceof Item) {
TreePath path = getTreePathFromItem((Item) widget);
elementChildren = getSortedChildren(path);
} else {
elementChildren = getSortedChildren(parent);
}
}
Control tree = getControl();
// WORKAROUND
int oldCnt = -1;
if (widget == tree) {
oldCnt = getItemCount(tree);
}
Item[] items = getChildren(widget);
// save the expanded elements
CustomHashtable expanded = newHashtable(CustomHashtable.DEFAULT_CAPACITY); // assume
// num
// expanded
// is
// small
for (int i = 0; i < items.length; ++i) {
if (getExpanded(items[i])) {
Object element = items[i].getData();
if (element != null) {
expanded.put(element, element);
}
}
}
int min = Math.min(elementChildren.length, items.length);
// dispose of surplus items, optimizing for the case where elements have
// been deleted but not reordered, or all elements have been removed.
int numItemsToDispose = items.length - min;
if (numItemsToDispose > 0) {
CustomHashtable children = newHashtable(elementChildren.length * 2);
for (int i = 0; i < elementChildren.length; i++) {
Object elementChild = elementChildren[i];
children.put(elementChild, elementChild);
}
int i = 0;
while (numItemsToDispose > 0 && i < items.length) {
Object data = items[i].getData();
if (data == null || items.length - i <= numItemsToDispose || !children.containsKey(data)) {
if (data != null) {
disassociate(items[i]);
}
items[i].dispose();
if (i + 1 < items.length) {
// The components at positions i+1 through
// items.length-1 in the source array are copied into
// positions i through items.length-2
System.arraycopy(items, i + 1, items, i, items.length - (i+1));
}
numItemsToDispose--;
} else {
i++;
}
}
}
// compare first min items, and update item if necessary
// need to do it in two passes:
// 1: disassociate old items
// 2: associate new items
// because otherwise a later disassociate can remove a mapping made for
// a previous associate,
// making the map inconsistent
for (int i = 0; i < min; ++i) {
Item item = items[i];
Object oldElement = item.getData();
if (oldElement != null) {
Object newElement = elementChildren[i];
if (newElement != oldElement) {
if (equals(newElement, oldElement)) {
// update the data to be the new element, since
// although the elements
// may be equal, they may still have different labels
// or children
Object data = item.getData();
if (data != null) {
unmapElement(data, item);
}
item.setData(newElement);
mapElement(newElement, item);
} else {
disassociate(item);
// Clear the text and image to force a label update
item.setImage(null);
item.setText("");//$NON-NLS-1$
}
}
}
}
for (int i = 0; i < min; ++i) {
Item item = items[i];
Object newElement = elementChildren[i];
if (item.getData() == null) {
// old and new elements are not equal
associate(newElement, item);
updatePlus(item, newElement);
updateItem(item, newElement);
} else {
// old and new elements are equal
updatePlus(item, newElement);
if (updateLabels) {
updateItem(item, newElement);
}
}
}
// Restore expanded state for items that changed position.
// Make sure setExpanded is called after updatePlus, since
// setExpanded(false) fails if item has no children.
// Need to call setExpanded for both expanded and unexpanded
// cases since the expanded state can change either way.
// This needs to be done in a second loop, see bug 148025.
for (int i = 0; i < min; ++i) {
Item item = items[i];
Object newElement = elementChildren[i];
setExpanded(item, expanded.containsKey(newElement));
}
// add any remaining elements
if (min < elementChildren.length) {
for (int i = min; i < elementChildren.length; ++i) {
createTreeItem(widget, elementChildren[i], -1);
}
// Need to restore expanded state in a separate pass
// because createTreeItem does not return the new item.
// Avoid doing this unless needed.
if (expanded.size() > 0) {
// get the items again, to include the new items
items = getChildren(widget);
for (int i = min; i < elementChildren.length; ++i) {
// Restore expanded state for items that changed position.
// Make sure setExpanded is called after updatePlus (called
// in createTreeItem), since
// setExpanded(false) fails if item has no children.
// Only need to call setExpanded if element was expanded
// since new items are initially unexpanded.
if (expanded.containsKey(elementChildren[i])) {
setExpanded(items[i], true);
}
}
}
}
// WORKAROUND
if (widget == tree && oldCnt == 0 && getItemCount(tree) != 0) {
// System.out.println("WORKAROUND setRedraw");
tree.setRedraw(false);
tree.setRedraw(true);
}
}
/** Returns true if children were pruned */
/*package*/ boolean optionallyPruneChildren(Item item, Object element) {
// need a dummy node if element is expandable;
// but try to avoid recreating the dummy node
boolean needDummy = isExpandable(item, null, element);
boolean haveDummy = false;
// remove all children
Item[] items = getItems(item);
for (int i = 0; i < items.length; i++) {
if (items[i].getData() != null) {
disassociate(items[i]);
items[i].dispose();
} else {
if (needDummy && !haveDummy) {
haveDummy = true;
} else {
items[i].dispose();
}
}
}
if (needDummy && !haveDummy) {
newItem(item, SWT.NULL, -1);
}
return true;
}
/**
* Not to be called by clients. Return the items to be refreshed as part of
* an update. elementChildren are the new elements.
*
* @param widget
* @param elementChildren
* @since 1.1
* @return Item[]
*
* @deprecated This method was inadvertently released as API but is not
* intended to be called by clients.
*/
public Item[] getChildren(Widget widget, Object[] elementChildren) {
return getChildren(widget);
}
/**
* Updates the "+"/"-" icon of the tree node from the given element. It
* calls isExpandable to determine whether an element is
* expandable.
*
* @param item
* the item
* @param element
* the element
*/
protected void updatePlus(Item item, Object element) {
boolean hasPlus = getItemCount(item) > 0;
boolean needsPlus = isExpandable(item, null, element);
boolean removeAll = false;
boolean addDummy = false;
Object data = item.getData();
if (data != null && equals(element, data)) {
// item shows same element
if (hasPlus != needsPlus) {
if (needsPlus) {
addDummy = true;
} else {
removeAll = true;
}
}
} else {
// item shows different element
removeAll = true;
addDummy = needsPlus;
// we cannot maintain expand state so collapse it
setExpanded(item, false);
}
if (removeAll) {
// remove all children
Item[] items = getItems(item);
for (int i = 0; i < items.length; i++) {
if (items[i].getData() != null) {
disassociate(items[i]);
}
items[i].dispose();
}
}
if (addDummy) {
newItem(item, SWT.NULL, -1); // append a dummy
}
}
/**
* Gets the expanded elements that are visible to the user. An expanded
* element is only visible if the parent is expanded.
*
* @return the visible expanded elements
* @since 1.0
*/
public Object[] getVisibleExpandedElements() {
ArrayList v = new ArrayList();
internalCollectVisibleExpanded(v, getControl());
return v.toArray();
}
private void internalCollectVisibleExpanded(ArrayList result, Widget widget) {
Item[] items = getChildren(widget);
for (int i = 0; i < items.length; i++) {
Item item = items[i];
if (getExpanded(item)) {
Object data = item.getData();
if (data != null) {
result.add(data);
}
// Only recurse if it is expanded - if
// not then the children aren't visible
internalCollectVisibleExpanded(result, item);
}
}
}
/**
* Returns the tree path for the given item.
* @param item
* @return {@link TreePath}
*
* @since 1.0
*/
protected TreePath getTreePathFromItem(Item item) {
LinkedList segments = new LinkedList();
while (item != null) {
Object segment = item.getData();
Assert.isNotNull(segment);
segments.addFirst(segment);
item = getParentItem(item);
}
return new TreePath(segments.toArray());
}
/**
* This implementation of getSelection() returns an instance of
* ITreeSelection.
*
* @since 1.0
*/
public ISelection getSelection() {
Control control = getControl();
if (control == null || control.isDisposed()) {
return TreeSelection.EMPTY;
}
Widget[] items = getSelection(getControl());
ArrayList list = new ArrayList(items.length);
for (int i = 0; i < items.length; i++) {
Widget item = items[i];
if (item.getData() != null) {
list.add(getTreePathFromItem((Item) item));
}
}
return new TreeSelection((TreePath[]) list.toArray(new TreePath[list
.size()]), getComparer());
}
protected void setSelectionToWidget(ISelection selection, boolean reveal) {
if (selection instanceof ITreeSelection) {
ITreeSelection treeSelection = (ITreeSelection) selection;
setSelectionToWidget(Arrays.asList(treeSelection.getPaths()),
reveal);
} else {
super.setSelectionToWidget(selection, reveal);
}
}
/**
* Returns a list of tree paths corresponding to expanded nodes in this
* viewer's tree, including currently hidden ones that are marked as
* expanded but are under a collapsed ancestor.
*
* This method is typically used when preserving the interesting state of a
* viewer; setExpandedElements is used during the restore.
*
*
* @return the array of expanded tree paths
* @see #setExpandedElements
*
* @since 1.0
*/
public TreePath[] getExpandedTreePaths() {
ArrayList items = new ArrayList();
internalCollectExpandedItems(items, getControl());
ArrayList result = new ArrayList(items.size());
for (Iterator it = items.iterator(); it.hasNext();) {
Item item = (Item) it.next();
TreePath treePath = getTreePathFromItem(item);
if (treePath != null) {
result.add(treePath);
}
}
return (TreePath[]) result.toArray(new TreePath[items.size()]);
}
private boolean isTreePathContentProvider() {
return getContentProvider() instanceof ITreePathContentProvider;
}
/**
* Inserts the given element as a new child element of the given parent
* element at the given position. If this viewer has a sorter, the position
* is ignored and the element is inserted at the correct position in the
* sort order.
*
* This method should be called (by the content provider) when elements have
* been added to the model, in order to cause the viewer to accurately
* reflect the model. This method only affects the viewer, not the model.
*
*
* @param parentElementOrTreePath
* the parent element, or the tree path to the parent
* @param element
* the element
* @param position
* a 0-based position relative to the model, or -1 to indicate
* the last position
*
* @since 1.0
*/
public void insert(Object parentElementOrTreePath, Object element,
int position) {
Assert.isNotNull(parentElementOrTreePath);
Assert.isNotNull(element);
if (checkBusy())
return;
if (getComparator() != null || hasFilters()) {
add(parentElementOrTreePath, new Object[] { element });
return;
}
Widget[] items;
if (internalIsInputOrEmptyPath(parentElementOrTreePath)) {
items = new Widget[] { getControl() };
} else {
items = internalFindItems(parentElementOrTreePath);
}
for (int i = 0; i < items.length; i++) {
Widget widget = items[i];
if (widget instanceof Item) {
Item item = (Item) widget;
Item[] childItems = getChildren(item);
if (getExpanded(item)
|| (childItems.length > 0 && childItems[0].getData() != null)) {
// item has real children, go ahead and add
int insertionPosition = position;
if (insertionPosition == -1) {
insertionPosition = getItemCount(item);
}
createTreeItem(item, element, insertionPosition);
} else {
Object parentElement = parentElementOrTreePath;
if (element instanceof TreePath)
parentElement = ((TreePath) parentElement).getLastSegment();
updatePlus(item, parentElement);
}
} else {
int insertionPosition = position;
if (insertionPosition == -1) {
insertionPosition = getItemCount((Control) widget);
}
createTreeItem(widget, element, insertionPosition);
}
}
}
/*
* (non-Javadoc)
*
* @see org.eclipse.jface.viewers.ColumnViewer#getColumnViewerOwner(int)
*/
protected Widget getColumnViewerOwner(int columnIndex) {
// Return null by default
return null;
}
/**
* This implementation of {@link #getItemAt(Point)} returns null to ensure
* API backwards compatibility. Subclasses should override.
*
* @since 1.0
*/
protected Item getItemAt(Point point) {
return null;
}
/**
* This implementation of {@link #createViewerEditor()} returns null to ensure
* API backwards compatibility. Subclasses should override.
*
* @since 1.0
*/
// RAP [bm]:
// protected ColumnViewerEditor createViewerEditor() {
// return null;
// }
/**
* Returns the number of columns of this viewer.
* Subclasses should overwrite this method, which has a default
* implementation (returning 0) for API backwards compatility reasons
*
* @return the number of columns
*
* @since 1.0
*/
protected int doGetColumnCount() {
return 0;
}
/**
* This implementation of buildLabel handles tree paths as well as elements.
*
* @param updateLabel
* the ViewerLabel to collect the result in
* @param elementOrPath
* the element or tree path for which a label should be built
*
* @see org.eclipse.jface.viewers.StructuredViewer#buildLabel(org.eclipse.jface.viewers.ViewerLabel,
* java.lang.Object)
*/
protected void buildLabel(ViewerLabel updateLabel, Object elementOrPath) {
Object element;
if (elementOrPath instanceof TreePath) {
TreePath path = (TreePath) elementOrPath;
IBaseLabelProvider provider = getLabelProvider();
if (provider instanceof ITreePathLabelProvider) {
ITreePathLabelProvider pprov = (ITreePathLabelProvider) provider;
buildLabel(updateLabel, path, pprov);
return;
}
element = path.getLastSegment();
} else {
element = elementOrPath;
}
super.buildLabel(updateLabel, element);
}
/**
* Returns true if the given object is either the input or an empty tree path.
*
* @param elementOrTreePath an element which could either be the viewer's input, or a tree path
*
* @return true if the given object is either the input or an empty tree path,
* false otherwise.
* @since 1.0
*/
final protected boolean internalIsInputOrEmptyPath(final Object elementOrTreePath) {
if (elementOrTreePath.equals(getRoot()))
return true;
if (!(elementOrTreePath instanceof TreePath))
return false;
return ((TreePath) elementOrTreePath).getSegmentCount() == 0;
}
/*
* Subclasses should implement
*/
protected ViewerRow getViewerRowFromItem(Widget item) {
return null;
}
}