org.eclipse.swt.widgets
Class Group

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.Group

All Implemented Interfaces:

Drawable

public class Group

extends Composite

Instances of this class provide an etched border with an optional title.

Shadow styles are hints and may not be honoured by the platform. To create a group with the default shadow style for the platform, do not specify a shadow style.

Styles:

SHADOW_ETCHED_IN, SHADOW_ETCHED_OUT, SHADOW_IN, SHADOW_OUT, SHADOW_NONE

Events:

(none)

Note: Only one of the above styles may be specified.

IMPORTANT: This class is not intended to be subclassed.

Field Summary

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

handle

Constructor Summary

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

Method Summary

protected void	checkSubclass() Checks that this class can be subclassed.
Point	computeSize(int wHint, int hHint, boolean changed) Returns the preferred size of the receiver.
Rectangle	computeTrim(int x, int y, int width, int height) Given a desired client area for the receiver (as described by the arguments), returns the bounding rectangle which would be required to produce that client area.
Rectangle	getClientArea() Returns a rectangle which describes the area of the receiver which is capable of displaying data (that is, not covered by the "trimmings").
String	getText() Returns the receiver's text, which is the string that the is used as the title.
void	setText(String string) Sets the receiver's text, which is the string that will be displayed as the receiver's title, to the argument, which may not be null.

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

getChildren, getLayout, getTabList, layout, layout, setFocus, setLayout, setTabList

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

getHorizontalBar, getVerticalBar

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

addControlListener, addFocusListener, addHelpListener, addKeyListener, addMouseListener, addMouseMoveListener, addMouseTrackListener, addPaintListener, addTraverseListener, computeSize, forceFocus, getAccessible, getBackground, getBorderWidth, getBounds, getDisplay, getEnabled, getFont, getForeground, getLayoutData, getLocation, getMenu, getParent, getShell, getSize, getToolTipText, getVisible, internal_dispose_GC, internal_new_GC, isDisposed, isEnabled, isFocusControl, isReparentable, isVisible, moveAbove, moveBelow, pack, pack, redraw, redraw, removeControlListener, removeFocusListener, removeHelpListener, removeKeyListener, removeMouseListener, removeMouseMoveListener, removeMouseTrackListener, removePaintListener, removeTraverseListener, setBackground, setBounds, setBounds, setCapture, setCursor, setEnabled, setFont, setForeground, setLayoutData, setLocation, setLocation, setMenu, setParent, setRedraw, setSize, setSize, setToolTipText, setVisible, toControl, toDisplay, traverse, update

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

addDisposeListener, addListener, checkWidget, dispose, getData, getData, getStyle, isListening, notifyListeners, removeDisposeListener, removeListener, removeListener, setData, setData, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

Group

public Group(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.SHADOW_ETCHED_IN, SWT.SHADOW_ETCHED_OUT, SWT.SHADOW_IN, SWT.SHADOW_OUT, SWT.SHADOW_NONE, Widget.checkSubclass(), Widget.getStyle()

Method Detail

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

computeSize

public Point computeSize(int wHint,
                         int hHint,
                         boolean changed)

Description copied from class: Control

Returns the preferred size of the receiver.

The preferred size of a control is the size that it would best be displayed at. The width hint and height hint arguments allow the caller to ask a control questions such as "Given a particular width, how high does the control need to be to show all of the contents?" To indicate that the caller does not wish to constrain a particular dimension, the constant SWT.DEFAULT is passed for the hint.

If the changed flag is true, it indicates that the receiver's contents have changed, therefore any caches that a layout manager containing the control may have been keeping need to be flushed. When the control is resized, the changed flag will be false, so layout manager caches can be retained.

Overrides:

computeSize in class Composite

Parameters:

wHint - the width hint (can be SWT.DEFAULT)

hHint - the height hint (can be SWT.DEFAULT)

changed - true if the control's contents have changed, and false otherwise

Returns:

the preferred size of the control.

See Also:

Layout, Control.getBorderWidth(), Control.getBounds(), Control.getSize(), Control.pack(), "computeTrim, getClientArea for controls that implement them"

computeTrim

public Rectangle computeTrim(int x,
                             int y,
                             int width,
                             int height)

Description copied from class: Scrollable

Given a desired client area for the receiver (as described by the arguments), returns the bounding rectangle which would be required to produce that client area.

In other words, it returns a rectangle such that, if the receiver's bounds were set to that rectangle, the area of the receiver which is capable of displaying data (that is, not covered by the "trimmings") would be the rectangle described by the arguments (relative to the receiver's parent).

Overrides:

computeTrim in class Scrollable

Returns:

the required bounds to produce the given client area

See Also:

Scrollable.getClientArea()

getClientArea

public Rectangle getClientArea()

Description copied from class: Scrollable

Returns a rectangle which describes the area of the receiver which is capable of displaying data (that is, not covered by the "trimmings").

Overrides:

getClientArea in class Scrollable

Returns:

the client area

See Also:

Scrollable.computeTrim(int, int, int, int)

getText

public String getText()

Returns the receiver's text, which is the string that the is used as the title. If the text has not previously been set, returns an empty string.

Returns:

the text

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

setText

public void setText(String string)

Sets the receiver's text, which is the string that will be displayed as the receiver's title, to the argument, which may not be null.

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