Package org.eclipse.swt.widgets

Class Shell

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.widgets.Decorations

org.eclipse.swt.widgets.Shell

All Implemented Interfaces:

Adaptable, Drawable

public class Shell
extends Decorations

Instances of this class represent the "windows" which the desktop or "window manager" is managing. Instances that do not have a parent (that is, they are built using the constructor, which takes a Display as the argument) are described as top level shells. Instances that do have a parent are described as secondary or dialog shells.

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

• When an instance is marked as maximized, the window manager will typically resize it to fill the entire visible area of the display, and the instance is usually put in a state where it can not be resized (even if it has style RESIZE) until it is no longer maximized.
• When an instance is in the normal state (neither maximized or minimized), its appearance is controlled by the style constants which were specified when it was created and the restrictions of the window manager (see below).
• When an instance has been marked as minimized, its contents (client area) will usually not be visible, and depending on the window manager, it may be "iconified" (that is, replaced on the desktop by a small simplified representation of itself), relocated to a distinguished area of the screen, or hidden. Combinations of these changes are also possible.

The modality of an instance may be specified using style bits. The modality style bits are used to determine whether input is blocked for other shells on the display. The PRIMARY_MODAL style allows an instance to block input to its parent. The APPLICATION_MODAL style allows an instance to block input to every other shell in the display. The SYSTEM_MODAL style allows an instance to block input to all shells, including shells belonging to different applications.

Note: The styles supported by this class are 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 and modality. For example, some window managers only support resizable windows and will always assume the RESIZE style, even if it is not set. In addition, if a modality style is not supported, it is "upgraded" to a more restrictive modality style that is supported. For example, if PRIMARY_MODAL is not supported, it would be upgraded to APPLICATION_MODAL. A modality style may also be "downgraded" to a less restrictive style. For example, most operating systems no longer support SYSTEM_MODAL because it can freeze up the desktop, so this is typically downgraded to APPLICATION_MODAL.

Styles:

BORDER, CLOSE, MIN, MAX, NO_TRIM, RESIZE, TITLE, ON_TOP, TOOL, SHEET

APPLICATION_MODAL, MODELESS, PRIMARY_MODAL, SYSTEM_MODAL

Events:

Activate, Close, Deactivate, Deiconify, Iconify

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)

Note: Only one of the styles APPLICATION_MODAL, MODELESS, PRIMARY_MODAL and SYSTEM_MODAL may be specified.

IMPORTANT: This class is not intended to be subclassed.

See Also:

• SWT

Constructor Summary

Constructors

Constructor	Description
Shell()	Constructs a new instance of this class.
Shell(int style)	Constructs a new instance of this class given only the style value describing its behavior and appearance.
Shell(Display display)	Constructs a new instance of this class given only the display to create it on.
Shell(Display display, int style)	Constructs a new instance of this class given the display to create it on and a style value describing its behavior and appearance.
Shell(Shell parent)	Constructs a new instance of this class given only its parent.
Shell(Shell parent, int style)	Constructs a new instance of this class given its parent and a style value describing its behavior and appearance.

Method Summary

Modifier and Type	Method	Description
void	addShellListener(ShellListener listener)	Adds the listener to the collection of listeners who will be notified when operations are performed on the receiver, by sending the listener one of the messages defined in the ShellListener interface.
void	close()	Requests that the window manager close the receiver in the same way it would be closed when the user clicks on the "close box" or performs some other platform specific key or mouse combination that indicates the window should be removed.
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	forceActive()	If the receiver is visible, moves it to the top of the drawing order for the display on which it was created (so that all other shells on that display, which are not the receiver's children will be drawn behind it) and forces the window manager to make the shell active.
<T> T	getAdapter(Class<T> adapter)	Implementation of the Adaptable interface.
int	getAlpha()	Returns the receiver's alpha value.
int	getBorderWidth()	Returns the receiver's border width.
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").
boolean	getFullScreen()	Returns true if the receiver is currently in fullscreen state, and false otherwise.
boolean	getMaximized()	Returns true if the receiver is currently maximized, and false otherwise.
boolean	getMinimized()	Returns true if the receiver is currently minimized, and false otherwise.
Point	getMinimumSize()	Returns a point describing the minimum receiver's size.
boolean	getModified()	Gets the receiver's modified state.
Shell[]	getShells()	Returns an array containing all shells which are descendents of the receiver.
ToolBar	getToolBar()	Returns the instance of the ToolBar object representing the tool bar that can appear on the trim of the shell.
boolean	isEnabled()	Returns true if the receiver is enabled and all ancestors up to and including the receiver's nearest ancestor shell are enabled.
boolean	isVisible()	Returns true if the receiver is visible and all ancestors up to and including the receiver's nearest ancestor shell are visible.
void	open()	Moves the receiver to the top of the drawing order for the display on which it was created (so that all other shells on that display, which are not the receiver's children will be drawn behind it), marks it visible, sets the focus and asks the window manager to make the shell active.
void	removeShellListener(ShellListener listener)	Removes the listener from the collection of listeners who will be notified when operations are performed on the receiver.
void	setActive()	If the receiver is visible, moves it to the top of the drawing order for the display on which it was created (so that all other shells on that display, which are not the receiver's children will be drawn behind it) and asks the window manager to make the shell active
void	setAlpha(int alpha)	Sets the receiver's alpha value.
void	setBounds(Rectangle bounds)	Sets the receiver's size and location to the rectangular area specified by the argument.
void	setEnabled(boolean enabled)	Enables the receiver if the argument is true, and disables it otherwise.
void	setFullScreen(boolean fullScreen)	Sets the full screen state of the receiver.
void	setMaximized(boolean maximized)	Sets the maximized state of the receiver.
void	setMinimized(boolean minimized)	Sets the minimized stated of the receiver.
void	setMinimumSize(int width, int height)	Sets the receiver's minimum size to the size specified by the arguments.
void	setMinimumSize(Point size)	Sets the receiver's minimum size to the size specified by the argument.
void	setModified(boolean modified)	Sets the receiver's modified state as specified by the argument.
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.Decorations

getDefaultButton, getImage, getImages, getMenuBar, getText, isReparentable, setDefaultButton, setImage, setImages, setMenuBar, setText

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

addPaintListener, removePaintListener

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

changed, computeSize, 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, getVerticalBar

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

addControlListener, addDragDetectListener, addFocusListener, addGestureListener, addHelpListener, addKeyListener, addMenuDetectListener, addMouseListener, addTouchListener, addTraverseListener, computeSize, forceFocus, getAccessible, getBackground, getBackgroundImage, getBounds, getCursor, getEnabled, getFont, getForeground, getLayoutData, getLocation, getMenu, getMonitor, getOrientation, getParent, getShell, getSize, getToolTipText, getTouchEnabled, getVisible, isFocusControl, moveAbove, moveBelow, pack, pack, redraw, redraw, removeControlListener, removeDragDetectListener, removeFocusListener, removeGestureListener, removeHelpListener, removeKeyListener, removeMenuDetectListener, removeMouseListener, removeTouchListener, removeTraverseListener, requestLayout, setBackground, setBackgroundImage, setBounds, setCursor, setData, setFont, setForeground, setLayoutData, setLocation, setLocation, setMenu, setOrientation, setParent, setRedraw, setSize, setSize, setToolTipText, setTouchEnabled, toControl, toControl, toDisplay, toDisplay, update

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

addDisposeListener, addListener, checkSubclass, checkWidget, dispose, getData, getData, getDisplay, getListeners, getStyle, isDisposed, isListening, notifyListeners, removeDisposeListener, removeListener, removeListener, reskin, setData, toString

Methods inherited from class java.lang.Object

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

Constructor Details

Shell

public Shell()

Constructs a new instance of this class. This is equivalent to calling Shell((Display) null).

Throws:

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

Since:

1.3

Shell

public Shell(int style)

Constructs a new instance of this class given only the style value describing its behavior and appearance. This is equivalent to calling Shell((Display) null, style).

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:

style - the style of control to construct

Throws:

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.SHEET

Shell

public Shell(Display display)

Constructs a new instance of this class given only the display to create it on. It is created with style SWT.SHELL_TRIM.

Note: Currently, null can be passed in for the display argument. This has the effect of creating the shell on the currently active display if there is one. If there is no current display, the shell is created on a "default" display. Passing in null as the display argument is not considered to be good coding style, and may not be supported in a future release of SWT.

Parameters:

display - the display to create the shell on

Throws:

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

Shell

public Shell(Display display,
 int style)

Constructs a new instance of this class given the display to create it on 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.

Note: Currently, null can be passed in for the display argument. This has the effect of creating the shell on the currently active display if there is one. If there is no current display, the shell is created on a "default" display. Passing in null as the display argument is not considered to be good coding style, and may not be supported in a future release of SWT.

Parameters:

display - the display to create the shell on

style - the style of control to construct

Throws:

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.MODELESS
• SWT.PRIMARY_MODAL
• SWT.APPLICATION_MODAL
• SWT.SYSTEM_MODAL
• SWT.SHEET

Shell

public Shell(Shell parent)

Constructs a new instance of this class given only its parent. It is created with style SWT.DIALOG_TRIM.

Note: Currently, null can be passed in for the parent. This has the effect of creating the shell on the currently active display if there is one. If there is no current display, the shell is created on a "default" display. Passing in null as the parent is not considered to be good coding style, and may not be supported in a future release of SWT.

Parameters:

parent - a shell which will be the parent of the new instance

Throws:

IllegalArgumentException -

• ERROR_INVALID_ARGUMENT - if the parent is disposed

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

Shell

public Shell(Shell 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.

Note: Currently, null can be passed in for the parent. This has the effect of creating the shell on the currently active display if there is one. If there is no current display, the shell is created on a "default" display. Passing in null as the parent is not considered to be good coding style, and may not be supported in a future release of SWT.

Parameters:

parent - a shell which will be the parent of the new instance

style - the style of control to construct

Throws:

IllegalArgumentException -

• ERROR_INVALID_ARGUMENT - if the parent is disposed

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

Method Details

getShells

public Shell[] getShells()

Returns an array containing all shells which are descendents of the receiver.

Returns:

the dialog shells

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

setActive

public void setActive()

If the receiver is visible, moves it to the top of the drawing order for the display on which it was created (so that all other shells on that display, which are not the receiver's children will be drawn behind it) and asks the window manager to make the shell active

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:

• Control.moveAbove(org.eclipse.swt.widgets.Control)
• Control.setFocus()
• Control.setVisible(boolean)
• Display.getActiveShell()
• Decorations.setDefaultButton(Button)
• open()
• setActive()

forceActive

public void forceActive()

If the receiver is visible, moves it to the top of the drawing order for the display on which it was created (so that all other shells on that display, which are not the receiver's children will be drawn behind it) and forces the window manager to make the shell active.

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:

1.2

See Also:

• Control.moveAbove(org.eclipse.swt.widgets.Control)
• Control.setFocus()
• Control.setVisible(boolean)
• Display.getActiveShell()
• Decorations.setDefaultButton(Button)
• open()
• setActive()

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)

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()

getBorderWidth

public int getBorderWidth()

Description copied from class: Control

Returns the receiver's border width. Note: When the theming defines different border widths for the four edges, this method returns the maximum border width.

Overrides:

getBorderWidth in class Control

Returns:

the border width

getAdapter

public <T> T getAdapter(Class<T> adapter)

Description copied from class: Widget

Implementation of the Adaptable interface.

IMPORTANT: This method is not part of the RWT public API. It is marked public only so that it can be shared within the packages provided by RWT. It should never be accessed from application code.

Specified by:

getAdapter in interface Adaptable

Overrides:

getAdapter in class Decorations

Parameters:

adapter - the lookup class

Returns:

an object that can be cast to the given class or null if there is no adapter associated with the given class.

setEnabled

public void setEnabled(boolean enabled)

Description copied from class: Control

Enables the receiver if the argument is true, and disables it otherwise. A disabled control is typically not selectable from the user interface and draws with an inactive or "grayed" look.

Overrides:

setEnabled in class Control

Parameters:

enabled - the new enabled state

isEnabled

public boolean isEnabled()

Description copied from class: Control

Returns true if the receiver is enabled and all ancestors up to and including the receiver's nearest ancestor shell are enabled. Otherwise, false is returned. A disabled control is typically not selectable from the user interface and draws with an inactive or "grayed" look.

Overrides:

isEnabled in class Control

Returns:

the receiver's enabled state

See Also:

• Control.getEnabled()

isVisible

public boolean isVisible()

Description copied from class: Control

Returns true if the receiver is visible and all ancestors up to and including the receiver's nearest ancestor shell are visible. Otherwise, false is returned.

Overrides:

isVisible in class Control

Returns:

the receiver's visibility state

See Also:

• Control.getVisible()

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

open

public void open()

Moves the receiver to the top of the drawing order for the display on which it was created (so that all other shells on that display, which are not the receiver's children will be drawn behind it), marks it visible, sets the focus and asks the window manager to make the shell active.

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:

• Control.moveAbove(org.eclipse.swt.widgets.Control)
• Control.setFocus()
• Control.setVisible(boolean)
• Display.getActiveShell()
• Decorations.setDefaultButton(Button)
• setActive()
• forceActive()

close

public void close()

Requests that the window manager close the receiver in the same way it would be closed when the user clicks on the "close box" or performs some other platform specific key or mouse combination that indicates the window should be removed.

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:

• SWT.Close
• Widget.dispose()

setAlpha

public void setAlpha(int alpha)

Sets the receiver's alpha value.

This operation may not be available on some platforms.

Parameters:

alpha - the alpha value

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:

1.1

getAlpha

public int getAlpha()

Returns the receiver's alpha value.

Returns:

the alpha value

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:

1.1

setModified

public void setModified(boolean modified)

Sets the receiver's modified state as specified by the argument.

Parameters:

modified - the new modified state for 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:

1.3

getModified

public boolean getModified()

Gets the receiver's modified state.