Package org.eclipse.swt.custom

Class TreeCursor

  • All Implemented Interfaces:
    Drawable
    public class TreeCursor
extends Canvas
    A TreeCursor provides a way for the user to navigate around a Tree with columns using the keyboard. It also provides a mechanism for selecting an individual cell in a tree.

    For a detailed example of using a TreeCursor to navigate to a cell and then edit it see http://git.eclipse.org/c/platform/eclipse.platform.swt.git/tree/examples/org.eclipse.swt.snippets/src/org/eclipse/swt/snippets/Snippet360.java .

    Styles:
    BORDER
    Events:
    Selection, DefaultSelection
    Since:
    3.8

    • Constructor Detail

      • TreeCursor

        public TreeCursor​(Tree parent,
                  int style)
        Constructs a new instance of this class given its parent tree 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 Tree 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.BORDER, 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 receiver's selection changes, 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 SWT.CHECK style set 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.

        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:
        SelectionListener, SelectionEvent, removeSelectionListener(SelectionListener)

      • getBackground

        public Color getBackground()
        Returns the background color that the receiver will use to draw.
        Overrides:
        getBackground in class Control
        Returns:
        the receiver's background color

      • getColumn

        public int getColumn()
        Returns the index of the column over which the TreeCursor is positioned.
        Returns:
        the column index for the current position
        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

      • getForeground

        public Color getForeground()
        Returns the foreground color that the receiver will use to draw.
        Overrides:
        getForeground in class Control
        Returns:
        the receiver's foreground color

      • getRow

        public TreeItem getRow()
        Returns the row over which the TreeCursor is positioned.
        Returns:
        the item for the current position, or null if none
        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

      • removeSelectionListener

        public void removeSelectionListener​(SelectionListener listener)
        Removes the listener from the collection of listeners who will be notified when the receiver's selection changes.
        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:
        SelectionListener, addSelectionListener(SelectionListener)

      • setBackground

        public void setBackground​(Color color)
        Sets the receiver's background color to the color specified by the argument, or to the default system color for the control if the argument is null.

        Note: This operation is a hint and may be overridden by the platform. For example, on Windows the background of a Button cannot be changed.

        Overrides:
        setBackground in class Control
        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

      • setForeground

        public void setForeground​(Color color)
        Sets the receiver's foreground color to the color specified by the argument, or to the default system color for the control if the argument is null.

        Note: This operation is a hint and may be overridden by the platform.

        Overrides:
        setForeground in class Control
        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

      • setSelection

        public void setSelection​(int row,
                         int column)
        Positions the TreeCursor over the root-level cell at the given row and column in the parent tree.
        Parameters:
        row - the index of the root-level row for the cell to select
        column - the index of column for the cell to select
        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

      • setSelection

        public void setSelection​(TreeItem row,
                         int column)
        Positions the TreeCursor over the cell at the given row and column in the parent tree.
        Parameters:
        row - the TreeItem of the row for the cell to select
        column - the index of column for the cell to select
        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

      • setVisible

        public void setVisible​(boolean visible)
        Description copied from class: Control
        Marks the receiver 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.

        Overrides:
        setVisible in class Control
        Parameters:
        visible - the new visibility state