Eclipse Platform
Release 4.2

org.eclipse.swt.widgets
Class Decorations

java.lang.Object
  extended by org.eclipse.swt.widgets.Widget
      extended by org.eclipse.swt.widgets.Control
          extended by org.eclipse.swt.widgets.Scrollable
              extended by org.eclipse.swt.widgets.Composite
                  extended by org.eclipse.swt.widgets.Canvas
                      extended by org.eclipse.swt.widgets.Decorations
All Implemented Interfaces:
Drawable
Direct Known Subclasses:
Shell

public class Decorations
extends Canvas

Instances of this class provide the appearance and behavior of Shells, but are not top level shells or dialogs. Class Shell shares a significant amount of code with this class, and is a subclass.

IMPORTANT: This class was intended to be abstract and should never be referenced or instantiated. Instead, the class Shell should be used.

Instances are always displayed in one of the maximized, minimized or normal states:

Note: The styles supported by this class must be treated as HINTs, since the window manager for the desktop on which the instance is visible has ultimate control over the appearance and behavior of decorations. For example, some window managers only support resizable windows and will always assume the RESIZE style, even if it is not set.
Styles:
BORDER, CLOSE, MIN, MAX, NO_TRIM, RESIZE, TITLE, ON_TOP, TOOL
Events:
(none)
Class SWT provides two "convenience constants" for the most commonly required style combinations:
SHELL_TRIM
the result of combining the constants which are required to produce a typical application top level shell: (that is, CLOSE | TITLE | MIN | MAX | RESIZE)
DIALOG_TRIM
the result of combining the constants which are required to produce a typical application dialog shell: (that is, TITLE | CLOSE | BORDER)

IMPORTANT: This class is intended to be subclassed only within the SWT implementation.

See Also:
getMinimized(), getMaximized(), Shell, SWT, Sample code and further information
Restriction:
This class is not intended to be subclassed by clients.

Field Summary
 
Fields inherited from class org.eclipse.swt.widgets.Control
handle
 
Constructor Summary
Decorations(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.
 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.
 void dispose()
          Disposes of the operating system resources associated with the receiver and all its descendants.
 Rectangle getBounds()
          Returns a rectangle describing the receiver's size and location relative to its parent (or its display if its parent is null), unless the receiver is a shell.
 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").
 Button getDefaultButton()
          Returns the receiver's default button if one had previously been set, otherwise returns null.
 Image getImage()
          Returns the receiver's image if it had previously been set using setImage().
 Image[] getImages()
          Returns the receiver's images if they had previously been set using setImages().
 Point getLocation()
          Returns a point describing the receiver's location relative to its parent (or its display if its parent is null), unless the receiver is a shell.
 boolean getMaximized()
          Returns true if the receiver is currently maximized, and false otherwise.
 Menu getMenuBar()
          Returns the receiver's menu bar if one had previously been set, otherwise returns null.
 boolean getMinimized()
          Returns true if the receiver is currently minimized, and false otherwise.
 Point getSize()
          Returns a point describing the receiver's size.
 String getText()
          Returns the receiver's text, which is the string that the window manager will typically display as the receiver's title.
 boolean isReparentable()
          Returns true if the underlying operating system supports this reparenting, otherwise false
 void setDefaultButton(Button button)
          If the argument is not null, sets the receiver's default button to the argument, and if the argument is null, sets the receiver's default button to the first button which was set as the receiver's default button (called the saved default button).
 void setImage(Image image)
          Sets the receiver's image to the argument, which may be null.
 void setImages(Image[] images)
          Sets the receiver's images to the argument, which may be an empty array.
 void setMaximized(boolean maximized)
          Sets the maximized state of the receiver.
 void setMenuBar(Menu menu)
          Sets the receiver's menu bar to the argument, which may be null.
 void setMinimized(boolean minimized)
          Sets the minimized stated of the receiver.
 void setOrientation(int orientation)
          Sets the orientation of the receiver, which must be one of the constants SWT.LEFT_TO_RIGHT or SWT.RIGHT_TO_LEFT.
 void setText(String string)
          Sets the receiver's text, which is the string that the window manager will typically display as the receiver's title, to the argument, which must not be null.
 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, computeSize, drawBackground, getBackgroundMode, getChildren, getLayout, getLayoutDeferred, getTabList, isLayoutDeferred, layout, layout, layout, layout, layout, setBackgroundMode, setFocus, setLayout, setLayoutDeferred, setTabList
 
Methods inherited from class org.eclipse.swt.widgets.Scrollable
getHorizontalBar, getScrollbarsMode, getVerticalBar
 
Methods inherited from class org.eclipse.swt.widgets.Control
addControlListener, addDragDetectListener, addFocusListener, addGestureListener, addHelpListener, addKeyListener, addMenuDetectListener, addMouseListener, addMouseMoveListener, addMouseTrackListener, addMouseWheelListener, addPaintListener, addTouchListener, addTraverseListener, computeSize, dragDetect, dragDetect, forceFocus, getAccessible, getBackground, getBackgroundImage, getBorderWidth, getCursor, getDragDetect, getEnabled, getFont, getForeground, getLayoutData, getMenu, getMonitor, getOrientation, getParent, getRegion, getShell, getToolTipText, getTouchEnabled, getVisible, internal_dispose_GC, internal_new_GC, isEnabled, isFocusControl, isVisible, moveAbove, moveBelow, pack, pack, print, redraw, redraw, removeControlListener, removeDragDetectListener, removeFocusListener, removeGestureListener, removeHelpListener, removeKeyListener, removeMenuDetectListener, removeMouseListener, removeMouseMoveListener, removeMouseTrackListener, removeMouseWheelListener, removePaintListener, removeTouchListener, removeTraverseListener, setBackground, setBackgroundImage, setBounds, setBounds, setCapture, setCursor, setDragDetect, setEnabled, setForeground, setLayoutData, setLocation, setLocation, setMenu, setParent, setRedraw, setRegion, setSize, setSize, setToolTipText, setTouchEnabled, toControl, toControl, toDisplay, toDisplay, traverse, traverse, traverse, update
 
Methods inherited from class org.eclipse.swt.widgets.Widget
addDisposeListener, addListener, checkWidget, getData, getData, getDisplay, getListeners, getStyle, isDisposed, isListening, notifyListeners, removeDisposeListener, removeListener, removeListener, reskin, setData, setData, toString
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
 

Constructor Detail

Decorations

public Decorations(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.BORDER, SWT.CLOSE, SWT.MIN, SWT.MAX, SWT.RESIZE, SWT.TITLE, SWT.NO_TRIM, SWT.SHELL_TRIM, SWT.DIALOG_TRIM, SWT.ON_TOP, SWT.TOOL, 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

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
Parameters:
x - the desired x coordinate of the client area
y - the desired y coordinate of the client area
width - the desired width of the client area
height - the desired height of the client area
Returns:
the required bounds to produce the given client area
See Also:
Scrollable.getClientArea()

dispose

public void dispose()
Description copied from class: Widget
Disposes of the operating system resources associated with the receiver and all its descendants. After this method has been invoked, the receiver and all descendants will answer true when sent the message isDisposed(). Any internal connections between the widgets in the tree will have been removed to facilitate garbage collection. This method does nothing if the widget is already disposed.

NOTE: This method is not called recursively on the descendants of the receiver. This means that, widget implementers can not detect when a widget is being disposed of by re-implementing this method, but should instead listen for the Dispose event.

Overrides:
dispose in class Widget
See Also:
Widget.addDisposeListener(org.eclipse.swt.events.DisposeListener), Widget.removeDisposeListener(org.eclipse.swt.events.DisposeListener), Widget.checkWidget()

getBounds

public Rectangle getBounds()
Description copied from class: Control
Returns a rectangle describing the receiver's size and location relative to its parent (or its display if its parent is null), unless the receiver is a shell. In this case, the location is relative to the display.

Overrides:
getBounds in class Control
Returns:
the receiver's bounding rectangle

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)

getDefaultButton

public Button getDefaultButton()
Returns the receiver's default button if one had previously been set, otherwise returns null.

Returns:
the default button or null
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:
setDefaultButton(Button)

getImage

public Image getImage()
Returns the receiver's image if it had previously been set using setImage(). The image is typically displayed by the window manager when the instance is marked as iconified, and may also be displayed somewhere in the trim when the instance is in normal or maximized states.

Note: This method will return null if called before setImage() is called. It does not provide access to a window manager provided, "default" image even if one exists.

Returns:
the image
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

getImages

public Image[] getImages()
Returns the receiver's images if they had previously been set using setImages(). Images are typically displayed by the window manager when the instance is marked as iconified, and may also be displayed somewhere in the trim when the instance is in normal or maximized states. Depending where the icon is displayed, the platform chooses the icon with the "best" attributes. It is expected that the array will contain the same icon rendered at different sizes, with different depth and transparency attributes.

Note: This method will return an empty array if called before setImages() is called. It does not provide access to a window manager provided, "default" image even if one exists.

Returns:
the images
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:
3.0

getLocation

public Point getLocation()
Description copied from class: Control
Returns a point describing the receiver's location relative to its parent (or its display if its parent is null), unless the receiver is a shell. In this case, the point is relative to the display.

Overrides:
getLocation in class Control
Returns:
the receiver's location

getMaximized

public boolean getMaximized()
Returns true if the receiver is currently maximized, and false otherwise.

Returns:
the maximized 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
See Also:
setMaximized(boolean)

getMenuBar

public Menu getMenuBar()
Returns the receiver's menu bar if one had previously been set, otherwise returns null.

Returns:
the menu bar or null
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

getMinimized

public boolean getMinimized()
Returns true if the receiver is currently minimized, and false otherwise.

Returns:
the minimized 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
See Also:
setMinimized(boolean)

getSize

public Point getSize()
Description copied from class: Control
Returns a point describing the receiver's size. The x coordinate of the result is the width of the receiver. The y coordinate of the result is the height of the receiver.

Overrides:
getSize in class Control
Returns:
the receiver's size

getText

public String getText()
Returns the receiver's text, which is the string that the window manager will typically display as the receiver's 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

isReparentable

public boolean isReparentable()
Description copied from class: Control
Returns true if the underlying operating system supports this reparenting, otherwise false

Overrides:
isReparentable in class Control
Returns:
true if the widget can be reparented, otherwise false

setDefaultButton

public void setDefaultButton(Button button)
If the argument is not null, sets the receiver's default button to the argument, and if the argument is null, sets the receiver's default button to the first button which was set as the receiver's default button (called the saved default button). If no default button had previously been set, or the saved default button was disposed, the receiver's default button will be set to null.

The default button is the button that is selected when the receiver is active and the user presses ENTER.

Parameters:
button - the new default button
Throws:
IllegalArgumentException -
  • ERROR_INVALID_ARGUMENT - if the button has been disposed
  • ERROR_INVALID_PARENT - if the control is not in the same widget tree
SWTException -
  • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
  • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver

setImage

public void setImage(Image image)
Sets the receiver's image to the argument, which may be null. The image is typically displayed by the window manager when the instance is marked as iconified, and may also be displayed somewhere in the trim when the instance is in normal or maximized states.

Parameters:
image - the new image (or null)
Throws:
IllegalArgumentException -
  • ERROR_INVALID_ARGUMENT - if the image 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

setImages

public void setImages(Image[] images)
Sets the receiver's images to the argument, which may be an empty array. Images are typically displayed by the window manager when the instance is marked as iconified, and may also be displayed somewhere in the trim when the instance is in normal or maximized states. Depending where the icon is displayed, the platform chooses the icon with the "best" attributes. It is expected that the array will contain the same icon rendered at different sizes, with different depth and transparency attributes.

Parameters:
images - the new image array
Throws:
IllegalArgumentException -
  • ERROR_NULL_ARGUMENT - if the array of images is null
  • ERROR_INVALID_ARGUMENT - if one of the images is null or 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:
3.0

setMaximized

public void setMaximized(boolean maximized)
Sets the maximized state of the receiver. If the argument is true causes the receiver to switch to the maximized state, and if the argument is false and the receiver was previously maximized, causes the receiver to switch back to either the minimized or normal states.

Note: The result of intermixing calls to setMaximized(true) and setMinimized(true) will vary by platform. Typically, the behavior will match the platform user's expectations, but not always. This should be avoided if possible.

Parameters:
maximized - the new maximized 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
See Also:
setMinimized(boolean)

setMenuBar

public void setMenuBar(Menu menu)
Sets the receiver's menu bar to the argument, which may be null.

Parameters:
menu - the new menu bar
Throws:
IllegalArgumentException -
  • ERROR_INVALID_ARGUMENT - if the menu has been disposed
  • ERROR_INVALID_PARENT - if the menu is not in the same widget tree
SWTException -
  • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
  • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver

setMinimized

public void setMinimized(boolean minimized)
Sets the minimized stated of the receiver. If the argument is true causes the receiver to switch to the minimized state, and if the argument is false and the receiver was previously minimized, causes the receiver to switch back to either the maximized or normal states.

Note: The result of intermixing calls to setMaximized(true) and setMinimized(true) will vary by platform. Typically, the behavior will match the platform user's expectations, but not always. This should be avoided if possible.

Parameters:
minimized - the new maximized 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
See Also:
setMaximized(boolean)

setOrientation

public void setOrientation(int orientation)
Description copied from class: Control
Sets the orientation of the receiver, which must be one of the constants SWT.LEFT_TO_RIGHT or SWT.RIGHT_TO_LEFT.

Overrides:
setOrientation in class Control
Parameters:
orientation - new orientation style

setText

public void setText(String string)
Sets the receiver's text, which is the string that the window manager will typically display as the receiver's title, to the argument, which must not be null.

Parameters:
string - the new text
Throws:
IllegalArgumentException -
  • ERROR_NULL_ARGUMENT - if the text 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

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

Eclipse Platform
Release 4.2

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