Tree

Instances of this class provide a selectable user interface object that displays a hierarchy of items and issues notification when an item in the hierarchy is selected. <p> The item children that may be added to instances of this class must be of type <code>TreeItem</code>. </p><p> Style <code>VIRTUAL</code> is used to create a <code>Tree</code> whose <code>TreeItem</code>s are to be populated by the client on an on-demand basis instead of up-front. This can provide significant performance improvements for trees that are very large or for which <code>TreeItem</code> population is expensive (for example, retrieving values from an external source). </p><p> Here is an example of using a <code>Tree</code> with style <code>VIRTUAL</code>: <code><pre> final Tree tree = new Tree(parent, SWT.VIRTUAL | SWT.BORDER); tree.setItemCount(20); tree.addListener(SWT.SetData, new Listener() { public void handleEvent(Event event) { TreeItem item = (TreeItem)event.item; TreeItem parentItem = item.getParentItem(); String text = null; if (parentItem is null) { text = "node " + tree.indexOf(item); } else { text = parentItem.getText() + " - " + parentItem.indexOf(item); } item.setText(text); System.out.println(text); item.setItemCount(10); } }); </pre></code> </p><p> Note that although this class is a subclass of <code>Composite</code>, it does not normally make sense to add <code>Control</code> children to it, or set a layout on it, unless implementing something like a cell editor. </p><p> <dl> <dt><b>Styles:</b></dt> <dd>SINGLE, MULTI, CHECK, FULL_SELECTION, VIRTUAL, NO_SCROLL</dd> <dt><b>Events:</b></dt> <dd>Selection, DefaultSelection, Collapse, Expand, SetData, MeasureItem, EraseItem, PaintItem</dd> </dl> </p><p> Note: Only one of the styles SINGLE and MULTI may be specified. </p><p> IMPORTANT: This class is <em>not</em> intended to be subclassed. </p>

@see <a href="http://www.eclipse.org/swt/snippets/#tree">Tree, TreeItem, TreeColumn snippets</a> @see <a href="http://www.eclipse.org/swt/examples.php">SWT Example: ControlExample</a> @see <a href="http://www.eclipse.org/swt/">Sample code and further information</a>

class Tree : Composite {

CallbackData treeSelectionCallbackData;

GtkTreeStore* modelHandle;

GtkCellRenderer* checkRenderer;

int columnCount;

int sortDirection;

GtkWidget* ignoreCell;

TreeItem[] items;

TreeColumn[] columns;

TreeColumn sortColumn;

TreeItem currentItem;

ImageList imageList;

ImageList headerImageList;

bool firstCustomDraw;

bool modelChanged;

bool expandAll;

int drawState;

int drawFlags;

GdkColor* drawForeground;

bool ownerDraw;

bool ignoreSize;

int ID_COLUMN;

int CHECKED_COLUMN;

int GRAYED_COLUMN;

int FOREGROUND_COLUMN;

int BACKGROUND_COLUMN;

int FONT_COLUMN;

int FIRST_COLUMN;

int CELL_PIXBUF;

int CELL_TEXT;

int CELL_FOREGROUND;

int CELL_BACKGROUND;

int CELL_FONT;

int CELL_TYPES;

this(Composite parent, int style);

void addSelectionListener(SelectionListener listener);

void addTreeListener(TreeListener listener);

void clear(int index, bool all);

void clearAll(bool all);

void deselect(TreeItem item);

void deselectAll();

TreeColumn getColumn(int index);

int getColumnCount();

int[] getColumnOrder();

TreeColumn[] getColumns();

int getGridLineWidth();

int getHeaderHeight();

bool getHeaderVisible();

TreeItem getItem(int index);

TreeItem getItem(Point point);

int getItemCount();

int getItemHeight();

TreeItem[] getItems();

bool getLinesVisible();

TreeItem getParentItem();

TreeItem[] getSelection();

int getSelectionCount();

TreeColumn getSortColumn();

int getSortDirection();

TreeItem getTopItem();

int indexOf(TreeColumn column);

int indexOf(TreeItem item);

void removeAll();

void removeSelectionListener(SelectionListener listener);

void removeTreeListener(TreeListener listener);

void setInsertMark(TreeItem item, bool before);

void setItemCount(int count);

void select(TreeItem item);

void selectAll();

void setColumnOrder(int[] order);

void setHeaderVisible(bool show);

void setLinesVisible(bool show);

void setSelection(TreeItem item);

void setSelection(TreeItem[] items);

void setSortColumn(TreeColumn column);

void setSortDirection(int direction);

void setTopItem(TreeItem item);

void showColumn(TreeColumn column);

void showSelection();

void showItem(TreeItem item);

}

Constructors

this this(Composite parent, int style): Constructs a new instance of this class given its parent and a style value describing its behavior and appearance. <p> The style value is either one of the style constants defined in class <code>SWT</code> which is applicable to instances of this class, or must be built by <em>bitwise OR</em>'ing together (that is, using the <code>int</code> "|" operator) two or more of those <code>SWT</code> style constants. The class description lists the style constants that are applicable to the class. Style bits are also inherited from superclasses. </p>

Members

Functions

addSelectionListener void addSelectionListener(SelectionListener listener): Adds the listener to the collection of listeners who will be notified when the user changes the receiver's selection, by sending it one of the messages defined in the <code>SelectionListener</code> interface. <p> When <code>widgetSelected</code> is called, the item field of the event object is valid. If the receiver has the <code>SWT.CHECK</code> style and the check selection changes, the event object detail field contains the value <code>SWT.CHECK</code>. <code>widgetDefaultSelected</code> is typically called when an item is double-clicked. The item field of the event object is valid for default selection, but the detail field is not used. </p>
addTreeListener void addTreeListener(TreeListener listener): Adds the listener to the collection of listeners who will be notified when an item in the receiver is expanded or collapsed by sending it one of the messages defined in the <code>TreeListener</code> interface.
clear void clear(int index, bool all): Clears the item at the given zero-relative index in the receiver. The text, icon and other attributes of the item are set to the default value. If the tree was created with the <code>SWT.VIRTUAL</code> style, these attributes are requested again as needed.
clearAll void clearAll(bool all): Clears all the items in the receiver. The text, icon and other attributes of the items are set to their default values. If the tree was created with the <code>SWT.VIRTUAL</code> style, these attributes are requested again as needed.
deselect void deselect(TreeItem item): Deselects an item in the receiver. If the item was already deselected, it remains deselected.
deselectAll void deselectAll(): Deselects all selected items in the receiver.
getColumn TreeColumn getColumn(int index): Returns the column at the given, zero-relative index in the receiver. Throws an exception if the index is out of range. Columns are returned in the order that they were created. If no <code>TreeColumn</code>s were created by the programmer, this method will throw <code>ERROR_INVALID_RANGE</code> despite the fact that a single column of data may be visible in the tree. This occurs when the programmer uses the tree like a list, adding items but never creating a column.
getColumnCount int getColumnCount(): Returns the number of columns contained in the receiver. If no <code>TreeColumn</code>s were created by the programmer, this value is zero, despite the fact that visually, one column of items may be visible. This occurs when the programmer uses the tree like a list, adding items but never creating a column.
getColumnOrder int[] getColumnOrder(): Returns an array of zero-relative integers that map the creation order of the receiver's items to the order in which they are currently being displayed. <p> Specifically, the indices of the returned array represent the current visual order of the items, and the contents of the array represent the creation order of the items. </p><p> Note: This is not the actual structure used by the receiver to maintain its list of items, so modifying the array will not affect the receiver. </p>
getColumns TreeColumn[] getColumns(): Returns an array of <code>TreeColumn</code>s which are the columns in the receiver. Columns are returned in the order that they were created. If no <code>TreeColumn</code>s were created by the programmer, the array is empty, despite the fact that visually, one column of items may be visible. This occurs when the programmer uses the tree like a list, adding items but never creating a column. <p> Note: This is not the actual structure used by the receiver to maintain its list of items, so modifying the array will not affect the receiver. </p>
getGridLineWidth int getGridLineWidth(): Returns the width in pixels of a grid line.
getHeaderHeight int getHeaderHeight(): Returns the height of the receiver's header
getHeaderVisible bool getHeaderVisible(): Returns <code>true</code> if the receiver's header is visible, and <code>false</code> otherwise. <p> If one of the receiver's ancestors is not visible or some other condition makes the receiver not visible, this method may still indicate that it is considered visible even though it may not actually be showing. </p>
getItem TreeItem getItem(int index): Returns the item at the given, zero-relative index in the receiver. Throws an exception if the index is out of range.
getItem TreeItem getItem(Point point): Returns the item at the given point in the receiver or null if no such item exists. The point is in the coordinate system of the receiver. <p> The item that is returned represents an item that could be selected by the user. For example, if selection only occurs in items in the first column, then null is returned if the point is outside of the item. Note that the SWT.FULL_SELECTION style hint, which specifies the selection policy, determines the extent of the selection. </p>
getItemCount int getItemCount(): Returns the number of items contained in the receiver that are direct item children of the receiver. The number that is returned is the number of roots in the tree.
getItemHeight int getItemHeight(): Returns the height of the area which would be used to display <em>one</em> of the items in the tree.
getItems TreeItem[] getItems(): Returns a (possibly empty) array of items contained in the receiver that are direct item children of the receiver. These are the roots of the tree. <p> Note: This is not the actual structure used by the receiver to maintain its list of items, so modifying the array will not affect the receiver. </p>
getLinesVisible bool getLinesVisible(): Returns <code>true</code> if the receiver's lines are visible, and <code>false</code> otherwise. <p> If one of the receiver's ancestors is not visible or some other condition makes the receiver not visible, this method may still indicate that it is considered visible even though it may not actually be showing. </p>
getParentItem TreeItem getParentItem(): Returns the receiver's parent item, which must be a <code>TreeItem</code> or null when the receiver is a root.
getSelection TreeItem[] getSelection(): Returns an array of <code>TreeItem</code>s that are currently selected in the receiver. The order of the items is unspecified. An empty array indicates that no items are selected. <p> Note: This is not the actual structure used by the receiver to maintain its selection, so modifying the array will not affect the receiver. </p> @return an array representing the selection
getSelectionCount int getSelectionCount(): Returns the number of selected items contained in the receiver.
getSortColumn TreeColumn getSortColumn(): Returns the column which shows the sort indicator for the receiver. The value may be null if no column shows the sort indicator.
getSortDirection int getSortDirection(): Returns the direction of the sort indicator for the receiver. The value will be one of <code>UP</code>, <code>DOWN</code> or <code>NONE</code>.
getTopItem TreeItem getTopItem(): Returns the item which is currently at the top of the receiver. This item can change when items are expanded, collapsed, scrolled or new items are added or removed.
indexOf int indexOf(TreeColumn column): Searches the receiver's list starting at the first column (index 0) until a column is found that is equal to the argument, and returns the index of that column. If no column is found, returns -1.
indexOf int indexOf(TreeItem item): Searches the receiver's list starting at the first item (index 0) until an item is found that is equal to the argument, and returns the index of that item. If no item is found, returns -1.
removeAll void removeAll(): Removes all of the items from the receiver.
removeSelectionListener void removeSelectionListener(SelectionListener listener): Removes the listener from the collection of listeners who will be notified when the user changes the receiver's selection.
removeTreeListener void removeTreeListener(TreeListener listener): Removes the listener from the collection of listeners who will be notified when items in the receiver are expanded or collapsed.
select void select(TreeItem item): Selects an item in the receiver. If the item was already selected, it remains selected.
selectAll void selectAll(): Selects all of the items in the receiver. <p> If the receiver is single-select, do nothing. </p>
setColumnOrder void setColumnOrder(int[] order): Sets the order that the items in the receiver should be displayed in to the given argument which is described in terms of the zero-relative ordering of when the items were added.
setHeaderVisible void setHeaderVisible(bool show): Marks the receiver's header as visible if the argument is <code>true</code>, and marks it invisible otherwise. <p> If one of the receiver's ancestors is not visible or some other condition makes the receiver not visible, marking it visible may not actually cause it to be displayed. </p>
setInsertMark void setInsertMark(TreeItem item, bool before): Display a mark indicating the point at which an item will be inserted. The drop insert item has a visual hint to show where a dragged item will be inserted when dropped on the tree.
setItemCount void setItemCount(int count): Sets the number of root-level items contained in the receiver.
setLinesVisible void setLinesVisible(bool show): Marks the receiver's lines as visible if the argument is <code>true</code>, and marks it invisible otherwise. <p> If one of the receiver's ancestors is not visible or some other condition makes the receiver not visible, marking it visible may not actually cause it to be displayed. </p>
setSelection void setSelection(TreeItem item): Sets the receiver's selection to the given item. The current selection is cleared before the new item is selected. <p> If the item is not in the receiver, then it is ignored. </p>
setSelection void setSelection(TreeItem[] items): Sets the receiver's selection to be the given array of items. The current selection is cleared before the new items are selected. <p> Items that are not in the receiver are ignored. If the receiver is single-select and multiple items are specified, then all items are ignored. </p>
setSortColumn void setSortColumn(TreeColumn column): Sets the column used by the sort indicator for the receiver. A null value will clear the sort indicator. The current sort column is cleared before the new column is set.
setSortDirection void setSortDirection(int direction): Sets the direction of the sort indicator for the receiver. The value can be one of <code>UP</code>, <code>DOWN</code> or <code>NONE</code>.
setTopItem void setTopItem(TreeItem item): Sets the item which is currently at the top of the receiver. This item can change when items are expanded, collapsed, scrolled or new items are added or removed.
showColumn void showColumn(TreeColumn column): Shows the column. If the column is already showing in the receiver, this method simply returns. Otherwise, the columns are scrolled until the column is visible.
showItem void showItem(TreeItem item): Shows the item. If the item is already showing in the receiver, this method simply returns. Otherwise, the items are scrolled and expanded until the item is visible.
showSelection void showSelection(): Shows the selection. If the selection is already showing in the receiver, this method simply returns. Otherwise, the items are scrolled until the selection is visible.

Inherited Members

From Composite

changed void changed(Control[] changed): Clears any data that has been cached by a Layout for all widgets that are in the parent hierarchy of the changed control up to and including the receiver. If an ancestor does not have a layout, it is skipped.
getBackgroundMode int getBackgroundMode(): Returns the receiver's background drawing mode. This will be one of the following constants defined in class <code>SWT</code>: <code>INHERIT_NONE</code>, <code>INHERIT_DEFAULT</code>, <code>INHERTIT_FORCE</code>.
getChildren Control[] getChildren(): Returns a (possibly empty) array containing the receiver's children. Children are returned in the order that they are drawn. The topmost control appears at the beginning of the array. Subsequent controls draw beneath this control and appear later in the array. <p> Note: This is not the actual structure used by the receiver to maintain its list of children, so modifying the array will not affect the receiver. </p>
getLayout Layout getLayout(): Returns layout which is associated with the receiver, or null if one has not been set.
getLayoutDeferred bool getLayoutDeferred(): Returns <code>true</code> if the receiver has deferred the performing of layout, and <code>false</code> otherwise.
getTabList Control[] getTabList(): Gets the (possibly empty) tabbing order for the control.
isLayoutDeferred bool isLayoutDeferred(): Returns <code>true</code> if the receiver or any ancestor up to and including the receiver's nearest ancestor shell has deferred the performing of layouts. Otherwise, <code>false</code> is returned.
layout void layout(): If the receiver has a layout, asks the layout to <em>lay out</em> (that is, set the size and location of) the receiver's children. If the receiver does not have a layout, do nothing. <p> This is equivalent to calling <code>layout(true)</code>. </p> <p> Note: Layout is different from painting. If a child is moved or resized such that an area in the parent is exposed, then the parent will paint. If no child is affected, the parent will not paint. </p>
layout void layout(bool changed): If the receiver has a layout, asks the layout to <em>lay out</em> (that is, set the size and location of) the receiver's children. If the argument is <code>true</code> the layout must not rely on any information it has cached about the immediate children. If it is <code>false</code> the layout may (potentially) optimize the work it is doing by assuming that none of the receiver's children has changed state since the last layout. If the receiver does not have a layout, do nothing. <p> If a child is resized as a result of a call to layout, the resize event will invoke the layout of the child. The layout will cascade down through all child widgets in the receiver's widget tree until a child is encountered that does not resize. Note that a layout due to a resize will not flush any cached information (same as <code>layout(false)</code>). </p> <p> Note: Layout is different from painting. If a child is moved or resized such that an area in the parent is exposed, then the parent will paint. If no child is affected, the parent will not paint. </p>
layout void layout(bool changed, bool all): If the receiver has a layout, asks the layout to <em>lay out</em> (that is, set the size and location of) the receiver's children. If the changed argument is <code>true</code> the layout must not rely on any information it has cached about its children. If it is <code>false</code> the layout may (potentially) optimize the work it is doing by assuming that none of the receiver's children has changed state since the last layout. If the all argument is <code>true</code> the layout will cascade down through all child widgets in the receiver's widget tree, regardless of whether the child has changed size. The changed argument is applied to all layouts. If the all argument is <code>false</code>, the layout will <em>not</em> cascade down through all child widgets in the receiver's widget tree. However, if a child is resized as a result of a call to layout, the resize event will invoke the layout of the child. Note that a layout due to a resize will not flush any cached information (same as <code>layout(false)</code>). </p> <p> Note: Layout is different from painting. If a child is moved or resized such that an area in the parent is exposed, then the parent will paint. If no child is affected, the parent will not paint. </p>
layout void layout(Control[] changed): Forces a lay out (that is, sets the size and location) of all widgets that are in the parent hierarchy of the changed control up to and including the receiver. The layouts in the hierarchy must not rely on any information cached about the changed control or any of its ancestors. The layout may (potentially) optimize the work it is doing by assuming that none of the peers of the changed control have changed state since the last layout. If an ancestor does not have a layout, skip it. <p> Note: Layout is different from painting. If a child is moved or resized such that an area in the parent is exposed, then the parent will paint. If no child is affected, the parent will not paint. </p>
setBackgroundMode void setBackgroundMode(int mode): Sets the background drawing mode to the argument which should be one of the following constants defined in class <code>SWT</code>: <code>INHERIT_NONE</code>, <code>INHERIT_DEFAULT</code>, <code>INHERIT_FORCE</code>.
setLayout void setLayout(Layout layout): Sets the layout which is associated with the receiver to be the argument which may be null.
setLayoutDeferred void setLayoutDeferred(bool defer): If the argument is <code>true</code>, causes subsequent layout operations in the receiver or any of its children to be ignored. No layout of any kind can occur in the receiver or any of its children until the flag is set to false. Layout operations that occurred while the flag was <code>true</code> are remembered and when the flag is set to <code>false</code>, the layout operations are performed in an optimized manner. Nested calls to this method are stacked.
setTabList void setTabList(Control[] tabList): Sets the tabbing order for the specified controls to match the order that they occur in the argument list.

Meta

Source

See Implementation