Package org.eclipse.swt.custom

Class TreeCursor

java.lang.Object

org.eclipse.swt.widgets.Widget

org.eclipse.swt.widgets.Control

org.eclipse.swt.widgets.Scrollable

org.eclipse.swt.widgets.Composite

org.eclipse.swt.widgets.Canvas

org.eclipse.swt.custom.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 https://github.com/eclipse-platform/eclipse.platform.swt/tree/master/examples/org.eclipse.swt.snippets/src/org/eclipse/swt/snippets/Snippet360.java .

Styles:

BORDER

Events:

Selection, DefaultSelection

Since:

3.8

Field Summary

Fields inherited from class org.eclipse.swt.widgets.Control

handle

Fields inherited from class org.eclipse.swt.widgets.Widget

nativeZoom

Constructor Summary

Constructors

Constructor	Description
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.

Method Summary

Modifier and Type	Method	Description
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.
Color	getBackground()	Returns the background color that the receiver will use to draw.
int	getColumn()	Returns the index of the column over which the TreeCursor is positioned.
Color	getForeground()	Returns the foreground color that the receiver will use to draw.
TreeItem	getRow()	Returns the row over which the TreeCursor is positioned.
void	removeSelectionListener(SelectionListener listener)	Removes the listener from the collection of listeners who will be notified when the receiver's selection changes.
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.
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.
void	setSelection(int row, int column)	Positions the TreeCursor over the root-level cell at the given row and column in the parent tree.
void	setSelection(TreeItem row, int column)	Positions the TreeCursor over the cell at the given row and column in the parent tree.
void	setVisible(boolean visible)	Marks the receiver as visible if the argument is true, and marks it invisible otherwise.

Methods inherited from class org.eclipse.swt.widgets.Canvas

drawBackground, getCaret, getIME, scroll, setCaret, setFont, setIME

Methods inherited from class org.eclipse.swt.widgets.Composite

changed, checkSubclass, drawBackground, getBackgroundMode, getChildren, getLayout, getLayoutDeferred, getTabList, isLayoutDeferred, layout, layout, layout, layout, layout, setBackgroundMode, setFocus, setLayout, setLayoutDeferred, setTabList, toString

Methods inherited from class org.eclipse.swt.widgets.Scrollable

computeTrim, getClientArea, getHorizontalBar, getScrollbarsMode, getVerticalBar, setScrollbarsMode

Methods inherited from class org.eclipse.swt.widgets.Control

addControlListener, addDragDetectListener, addFocusListener, addGestureListener, addHelpListener, addKeyListener, addMenuDetectListener, addMouseListener, addMouseMoveListener, addMouseTrackListener, addMouseWheelListener, addPaintListener, addTouchListener, addTraverseListener, computeSize, computeSize, dragDetect, dragDetect, forceFocus, getAccessible, getBackgroundImage, getBorderWidth, getBounds, getCursor, getDragDetect, getEnabled, getFont, getLayoutData, getLocation, getMenu, getMonitor, getOrientation, getParent, getRegion, getShell, getSize, getTextDirection, getToolTipText, getTouchEnabled, getVisible, internal_dispose_GC, internal_new_GC, isEnabled, isFocusControl, isReparentable, isVisible, moveAbove, moveBelow, pack, pack, print, redraw, redraw, removeControlListener, removeDragDetectListener, removeFocusListener, removeGestureListener, removeHelpListener, removeKeyListener, removeMenuDetectListener, removeMouseListener, removeMouseMoveListener, removeMouseTrackListener, removeMouseWheelListener, removePaintListener, removeTouchListener, removeTraverseListener, requestLayout, setBackgroundImage, setBounds, setBounds, setCapture, setCursor, setDragDetect, setEnabled, setLayoutData, setLocation, setLocation, setMenu, setOrientation, setParent, setRedraw, setRegion, setSize, setSize, setTextDirection, setToolTipText, setTouchEnabled, toControl, toControl, toDisplay, toDisplay, traverse, traverse, traverse, update

Methods inherited from class org.eclipse.swt.widgets.Widget

addDisposeListener, addListener, addTypedListener, checkWidget, dispose, getData, getData, getDisplay, getListeners, getStyle, getTypedListeners, isAutoDirection, isDisposed, isListening, notifyListeners, removeDisposeListener, removeListener, removeListener, removeTypedListener, reskin, setData, setData

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.eclipse.swt.graphics.Drawable

isAutoScalable

Constructor Details

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 Details

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