Package org.eclipse.swt.widgets

Class Tree

  • All Implemented Interfaces:
    Drawable
    public class Tree
extends Composite
    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.

    The item children that may be added to instances of this class must be of type TreeItem.

    Style VIRTUAL is used to create a Tree whose TreeItems 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 TreeItem population is expensive (for example, retrieving values from an external source).

    Here is an example of using a Tree with style VIRTUAL:

    
  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 == null) {
              text = "node " + tree.indexOf(item);
          } else {
              text = parentItem.getText() + " - " + parentItem.indexOf(item);
          }
          item.setText(text);
          System.out.println(text);
          item.setItemCount(10);
      }
  });

    Note that although this class is a subclass of Composite, it does not normally make sense to add Control children to it, or set a layout on it, unless implementing something like a cell editor.

    Styles:
    SINGLE, MULTI, CHECK, FULL_SELECTION, VIRTUAL, NO_SCROLL
    Events:
    Selection, DefaultSelection, Collapse, Expand, SetData, MeasureItem, EraseItem, PaintItem, EmptinessChanged

    Note: Only one of the styles SINGLE and MULTI may be specified.

    IMPORTANT: This class is not intended to be subclassed.

    See Also:
    Tree, TreeItem, TreeColumn snippets, SWT Example: ControlExample, Sample code and further information
    Restriction:
    This class is not intended to be subclassed by clients.

    • Constructor Detail

      • Tree

        public Tree​(Composite parent,
            int style)
        Constructs a new instance of this class given its parent and a style value describing its behavior and appearance.

        The style value is either one of the style constants defined in class SWT which is applicable to instances of this class, or must be built by bitwise OR'ing together (that is, using the int "|" operator) two or more of those SWT style constants. The class description lists the style constants that are applicable to the class. Style bits are also inherited from superclasses.

        Parameters:
        parent - a composite control which will be the parent of the new instance (cannot be null)
        style - the style of control to construct
        Throws:
        IllegalArgumentException -
        • ERROR_NULL_ARGUMENT - if the parent is null
        SWTException -
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent
        • ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass
        See Also:
        SWT.SINGLE, SWT.MULTI, SWT.CHECK, SWT.FULL_SELECTION, SWT.VIRTUAL, SWT.NO_SCROLL, Widget.checkSubclass(), Widget.getStyle()

    • Method Detail

      • addSelectionListener

        public 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 SelectionListener interface.

        When widgetSelected is called, the item field of the event object is valid. If the receiver has the SWT.CHECK style and the check selection changes, the event object detail field contains the value SWT.CHECK. widgetDefaultSelected 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.

        Parameters:
        listener - the listener which should be notified when the user changes the receiver's selection
        Throws:
        IllegalArgumentException -
        • ERROR_NULL_ARGUMENT - if the listener is null
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        See Also:
        SelectionListener, removeSelectionListener(org.eclipse.swt.events.SelectionListener), SelectionEvent

      • addTreeListener

        public 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 TreeListener interface.
        Parameters:
        listener - the listener which should be notified
        Throws:
        IllegalArgumentException -
        • ERROR_NULL_ARGUMENT - if the listener is null
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        See Also:
        TreeListener, removeTreeListener(org.eclipse.swt.events.TreeListener)

      • checkSubclass

        protected void checkSubclass()
        Description copied from class: Widget
        Checks that this class can be subclassed.

        The SWT class library is intended to be subclassed only at specific, controlled points (most notably, Composite and Canvas when implementing new widgets). This method enforces this rule unless it is overridden.

        IMPORTANT: By providing an implementation of this method that allows a subclass of a class which does not normally allow subclassing to be created, the implementer agrees to be fully responsible for the fact that any such subclass will likely fail between SWT releases and will be strongly platform specific. No support is provided for user-written classes which are implemented in this fashion.

        The ability to subclass outside of the allowed SWT classes is intended purely to enable those not on the SWT development team to implement patches in order to get around specific limitations in advance of when those limitations can be addressed by the team. Subclassing should not be attempted without an intimate and detailed understanding of the hierarchy.

        Overrides:
        checkSubclass in class Composite

      • clear

        public void clear​(int index,
                  boolean 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 SWT.VIRTUAL style, these attributes are requested again as needed.
        Parameters:
        index - the index of the item to clear
        all - true if all child items of the indexed item should be cleared recursively, and false otherwise
        Throws:
        IllegalArgumentException -
        • ERROR_INVALID_RANGE - if the index is not between 0 and the number of elements in the list minus 1 (inclusive)
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        Since:
        3.2
        See Also:
        SWT.VIRTUAL, SWT.SetData

      • clearAll

        public void clearAll​(boolean 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 SWT.VIRTUAL style, these attributes are requested again as needed.
        Parameters:
        all - true if all child items should be cleared recursively, and false otherwise
        Throws:
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        Since:
        3.2
        See Also:
        SWT.VIRTUAL, SWT.SetData

      • deselect

        public void deselect​(TreeItem item)
        Deselects an item in the receiver. If the item was already deselected, it remains deselected.
        Parameters:
        item - the item to be deselected
        Throws:
        IllegalArgumentException -
        • ERROR_NULL_ARGUMENT - if the item is null
        • ERROR_INVALID_ARGUMENT - if the item has been disposed
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        Since:
        3.4

      • deselectAll

        public void deselectAll()
        Deselects all selected items in the receiver.
        Throws:
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver

      • getGridLineWidth

        public int getGridLineWidth()
        Returns the width in points of a grid line.
        Returns:
        the width of a grid line in points
        Throws:
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        Since:
        3.1

      • getHeaderBackground

        public Color getHeaderBackground()
        Returns the header background color.
        Returns:
        the receiver's header background color.
        Throws:
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        Since:
        3.106

      • getHeaderForeground

        public Color getHeaderForeground()
        Returns the header foreground color.
        Returns:
        the receiver's header foreground color.
        Throws:
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        Since:
        3.106

      • getHeaderHeight

        public int getHeaderHeight()
        Returns the height of the receiver's header
        Returns:
        the height of the header or zero if the header is not visible
        Throws:
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        Since:
        3.1

      • getHeaderVisible

        public boolean getHeaderVisible()
        Returns true if the receiver's header is visible, and false otherwise.

        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.

        Returns:
        the receiver's header's visibility state
        Throws:
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        Since:
        3.1

      • getColumn

        public 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 TreeColumns were created by the programmer, this method will throw ERROR_INVALID_RANGE 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.
        Parameters:
        index - the index of the column to return
        Returns:
        the column at the given index
        Throws:
        IllegalArgumentException -
        • ERROR_INVALID_RANGE - if the index is not between 0 and the number of elements in the list minus 1 (inclusive)
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        Since:
        3.1
        See Also:
        getColumnOrder(), setColumnOrder(int[]), TreeColumn.getMoveable(), TreeColumn.setMoveable(boolean), SWT.Move

      • getColumnCount

        public int getColumnCount()
        Returns the number of columns contained in the receiver. If no TreeColumns 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.
        Returns:
        the number of columns
        Throws:
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        Since:
        3.1

      • getColumnOrder

        public 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.

        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.

        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.

        Returns:
        the current visual order of the receiver's items
        Throws:
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        Since:
        3.2
        See Also:
        setColumnOrder(int[]), TreeColumn.getMoveable(), TreeColumn.setMoveable(boolean), SWT.Move

      • getColumns

        public TreeColumn[] getColumns()
        Returns an array of TreeColumns which are the columns in the receiver. Columns are returned in the order that they were created. If no TreeColumns 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.

        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.

        Returns:
        the items in the receiver
        Throws:
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        Since:
        3.1
        See Also:
        getColumnOrder(), setColumnOrder(int[]), TreeColumn.getMoveable(), TreeColumn.setMoveable(boolean), SWT.Move

      • getItem

        public 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.
        Parameters:
        index - the index of the item to return
        Returns:
        the item at the given index
        Throws:
        IllegalArgumentException -
        • ERROR_INVALID_RANGE - if the index is not between 0 and the number of elements in the list minus 1 (inclusive)
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        Since:
        3.1

      • getItem

        public 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.

        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.

        Parameters:
        point - the point used to locate the item
        Returns:
        the item at the given point, or null if the point is not in a selectable item
        Throws:
        IllegalArgumentException -
        • ERROR_NULL_ARGUMENT - if the point is null
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver

      • getItemCount

        public 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.
        Returns:
        the number of items
        Throws:
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver

      • getItemHeight

        public int getItemHeight()
        Returns the height of the area which would be used to display one of the items in the tree.
        Returns:
        the height of one item
        Throws:
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver

      • getItems

        public 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.

        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.

        Returns:
        the items
        Throws:
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver

      • getLinesVisible

        public boolean getLinesVisible()
        Returns true if the receiver's lines are visible, and false otherwise. Note that some platforms draw grid lines while others may draw alternating row colors.

        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.

        Returns:
        the visibility state of the lines
        Throws:
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        Since:
        3.1

      • getParentItem

        public TreeItem getParentItem()
        Returns the receiver's parent item, which must be a TreeItem or null when the receiver is a root.
        Returns:
        the receiver's parent item
        Throws:
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver

      • getSelection

        public TreeItem[] getSelection()
        Returns an array of TreeItems that are currently selected in the receiver. The order of the items is unspecified. An empty array indicates that no items are selected.

        Note: This is not the actual structure used by the receiver to maintain its selection, so modifying the array will not affect the receiver.

        Returns:
        an array representing the selection
        Throws:
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver

      • getSelectionCount

        public int getSelectionCount()
        Returns the number of selected items contained in the receiver.
        Returns:
        the number of selected items
        Throws:
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver

      • getSortColumn

        public 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.
        Returns:
        the sort indicator
        Throws:
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        Since:
        3.2
        See Also:
        setSortColumn(TreeColumn)

      • getSortDirection

        public int getSortDirection()
        Returns the direction of the sort indicator for the receiver. The value will be one of UP, DOWN or NONE.
        Returns:
        the sort direction
        Throws:
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        Since:
        3.2
        See Also:
        setSortDirection(int)

      • getTopItem

        public 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.
        Returns:
        the item at the top of the receiver
        Throws:
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        Since:
        2.1

      • indexOf

        public 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.
        Parameters:
        column - the search column
        Returns:
        the index of the column
        Throws:
        IllegalArgumentException -
        • ERROR_NULL_ARGUMENT - if the column is null
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        Since:
        3.1

      • indexOf

        public 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.
        Parameters:
        item - the search item
        Returns:
        the index of the item
        Throws:
        IllegalArgumentException -
        • ERROR_NULL_ARGUMENT - if the item is null
        • ERROR_INVALID_ARGUMENT - if the item has been disposed
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        Since:
        3.1

      • removeAll

        public void removeAll()
        Removes all of the items from the receiver.
        Throws:
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver

      • removeTreeListener

        public 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.
        Parameters:
        listener - the listener which should no longer be notified
        Throws:
        IllegalArgumentException -
        • ERROR_NULL_ARGUMENT - if the listener is null
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        See Also:
        TreeListener, addTreeListener(org.eclipse.swt.events.TreeListener)

      • setInsertMark

        public void setInsertMark​(TreeItem item,
                          boolean 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.
        Parameters:
        item - the insert item. Null will clear the insertion mark.
        before - true places the insert mark above 'item'. false places the insert mark below 'item'.
        Throws:
        IllegalArgumentException -
        • ERROR_INVALID_ARGUMENT - if the item has been disposed
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver

      • setItemCount

        public void setItemCount​(int count)
        Sets the number of root-level items contained in the receiver.

        The fastest way to insert many items is documented in TreeItem(Tree,int,int) and TreeItem.setItemCount(int)

        Parameters:
        count - the number of items
        Throws:
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        Since:
        3.2

      • setLinesVisible

        public void setLinesVisible​(boolean show)
        Marks the receiver's lines as visible if the argument is true, and marks it invisible otherwise. Note that some platforms draw grid lines while others may draw alternating row colors.

        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.

        Parameters:
        show - the new visibility state
        Throws:
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        Since:
        3.1

      • select

        public void select​(TreeItem item)
        Selects an item in the receiver. If the item was already selected, it remains selected.
        Parameters:
        item - the item to be selected
        Throws:
        IllegalArgumentException -
        • ERROR_NULL_ARGUMENT - if the item is null
        • ERROR_INVALID_ARGUMENT - if the item has been disposed
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        Since:
        3.4

      • selectAll

        public void selectAll()
        Selects all of the items in the receiver.

        If the receiver is single-select, do nothing.

        Throws:
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver

      • setColumnOrder

        public 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.
        Parameters:
        order - the new order to display the items
        Throws:
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        IllegalArgumentException -
        • ERROR_NULL_ARGUMENT - if the item order is null
        • ERROR_INVALID_ARGUMENT - if the item order is not the same length as the number of items
        Since:
        3.2
        See Also:
        getColumnOrder(), TreeColumn.getMoveable(), TreeColumn.setMoveable(boolean), SWT.Move

      • setFont

        public void setFont​(Font font)
        Description copied from class: Control
        Sets the font that the receiver will use to paint textual information to the font specified by the argument, or to the default font for that kind of control if the argument is null.
        Overrides:
        setFont in class Control
        Parameters:
        font - the new font (or null)

      • setHeaderBackground

        public void setHeaderBackground​(Color color)
        Sets the header background color to the color specified by the argument, or to the default system color if the argument is null.

        Note: This operation is a HINT and is not supported on all platforms. If the native header has a 3D look and feel (e.g. Windows 7), this method will cause the header to look FLAT irrespective of the state of the tree style.

        Parameters:
        color - the new color (or null)
        Throws:
        IllegalArgumentException -
        • ERROR_INVALID_ARGUMENT - if the argument has been disposed
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        Since:
        3.106

      • setHeaderForeground

        public void setHeaderForeground​(Color color)
        Sets the header foreground color to the color specified by the argument, or to the default system color if the argument is null.

        Note: This operation is a HINT and is not supported on all platforms. If the native header has a 3D look and feel (e.g. Windows 7), this method will cause the header to look FLAT irrespective of the state of the tree style.

        Parameters:
        color - the new color (or null)
        Throws:
        IllegalArgumentException -
        • ERROR_INVALID_ARGUMENT - if the argument has been disposed
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        Since:
        3.106

      • setHeaderVisible

        public void setHeaderVisible​(boolean show)
        Marks the receiver's header as visible if the argument is true, and marks it invisible otherwise.

        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.

        Parameters:
        show - the new visibility state
        Throws:
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        Since:
        3.1

      • setRedraw

        public void setRedraw​(boolean redraw)
        Description copied from class: Control
        If the argument is false, causes subsequent drawing operations in the receiver to be ignored. No drawing of any kind can occur in the receiver until the flag is set to true. Graphics operations that occurred while the flag was false are lost. When the flag is set to true, the entire widget is marked as needing to be redrawn. Nested calls to this method are stacked.

        Note: This operation is a hint and may not be supported on some platforms or for some widgets.

        Overrides:
        setRedraw in class Control
        Parameters:
        redraw - the new redraw state
        See Also:
        Control.redraw(int, int, int, int, boolean), Control.update()

      • setSelection

        public void setSelection​(TreeItem item)
        Sets the receiver's selection to the given item. The current selection is cleared before the new item is selected, and if necessary the receiver is scrolled to make the new selection visible.

        If the item is not in the receiver, then it is ignored.

        Parameters:
        item - the item to select
        Throws:
        IllegalArgumentException -
        • ERROR_NULL_ARGUMENT - if the item is null
        • ERROR_INVALID_ARGUMENT - if the item has been disposed
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        Since:
        3.2

      • setSelection

        public 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, and if necessary the receiver is scrolled to make the new selection visible.

        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.

        Parameters:
        items - the array of items
        Throws:
        IllegalArgumentException -
        • ERROR_NULL_ARGUMENT - if the array of items is null
        • ERROR_INVALID_ARGUMENT - if one of the items has been disposed
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        See Also:
        deselectAll()

      • setSortColumn

        public 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.
        Parameters:
        column - the column used by the sort indicator or null
        Throws:
        IllegalArgumentException -
        • ERROR_INVALID_ARGUMENT - if the column is disposed
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        Since:
        3.2

      • setSortDirection

        public void setSortDirection​(int direction)
        Sets the direction of the sort indicator for the receiver. The value can be one of UP, DOWN or NONE.
        Parameters:
        direction - the direction of the sort indicator
        Throws:
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        Since:
        3.2

      • setTopItem

        public 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.
        Parameters:
        item - the item to be shown
        Throws:
        IllegalArgumentException -
        • ERROR_NULL_ARGUMENT - if the item is null
        • ERROR_INVALID_ARGUMENT - if the item has been disposed
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        Since:
        2.1
        See Also:
        getTopItem()

      • showColumn

        public 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.
        Parameters:
        column - the column to be shown
        Throws:
        IllegalArgumentException -
        • ERROR_NULL_ARGUMENT - if the item is null
        • ERROR_INVALID_ARGUMENT - if the item has been disposed
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        Since:
        3.1

      • showItem

        public 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.
        Parameters:
        item - the item to be shown
        Throws:
        IllegalArgumentException -
        • ERROR_NULL_ARGUMENT - if the item is null
        • ERROR_INVALID_ARGUMENT - if the item has been disposed
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        See Also:
        showSelection()

      • showSelection

        public 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.
        Throws:
        SWTException -
        • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
        • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
        See Also:
        showItem(TreeItem)