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:
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_MOVE, 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:
Restriction:
This class is not intended to be subclassed by clients.

  • 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

    • 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:

    • 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:

    • 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:

  • Method Details

    • win32_new

      public static Shell win32_new(Display display, long handle)
      Invokes platform specific functionality to allocate a new shell that is embedded.

      IMPORTANT: This method is not part of the public API for Shell. It is marked public only so that it can be shared within the packages provided by SWT. It is not available on all platforms, and should never be called from application code.

      Parameters:
      display - the display for the shell
      handle - the handle for the shell
      Returns:
      a new shell object containing the specified display and handle
      Restriction:
      This method is not intended to be referenced by clients.

    • internal_new

      public static Shell internal_new(Display display, long handle)
      Invokes platform specific functionality to allocate a new shell that is not embedded.

      IMPORTANT: This method is not part of the public API for Shell. It is marked public only so that it can be shared within the packages provided by SWT. It is not available on all platforms, and should never be called from application code.

      Parameters:
      display - the display for the shell
      handle - the handle for the shell
      Returns:
      a new shell object containing the specified display and handle
      Since:
      3.3
      Restriction:
      This method is not intended to be referenced by clients.

    • addShellListener

      public 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.
      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:

    • 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:

    • 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:
      2.0
      See Also:

    • getAlpha

      public int getAlpha()
      Returns the receiver's alpha value. The alpha value is between 0 (transparent) and 255 (opaque).
      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:
      3.4

    • getEnabled

      public boolean getEnabled()
      Description copied from class: Control
      Returns true if the receiver is enabled, and false otherwise. A disabled control is typically not selectable from the user interface and draws with an inactive or "grayed" look.
      Overrides:
      getEnabled in class Control
      Returns:
      the receiver's enabled state
      See Also:

    • getFullScreen

      public boolean getFullScreen()
      Returns true if the receiver is currently in fullscreen state, and false otherwise.
      Returns:
      the fullscreen 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
      Since:
      3.4

    • getImeInputMode

      public int getImeInputMode()
      Returns the receiver's input method editor mode. This will be the result of bitwise OR'ing together one or more of the following constants defined in class SWT: NONE, ROMAN, DBCS, PHONETIC, NATIVE, ALPHA.
      Returns:
      the IME mode
      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:

    • getMaximized

      public boolean getMaximized()
      Description copied from class: Decorations
      Returns true if the receiver is currently maximized, and false otherwise.
      Overrides:
      getMaximized in class Decorations
      Returns:
      the maximized state
      See Also:

    • getMaximumSize

      public Point getMaximumSize()
      Returns a point describing the maximum receiver's size. The x coordinate of the result is the maximum width of the receiver. The y coordinate of the result is the maximum height of the receiver.
      Returns:
      the receiver's size
      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:
      3.116

    • getMinimumSize

      public Point getMinimumSize()
      Returns a point describing the minimum receiver's size. The x coordinate of the result is the minimum width of the receiver. The y coordinate of the result is the minimum height of the receiver.
      Returns:
      the receiver's size
      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:
      3.1

    • getModified

      public boolean getModified()
      Gets the receiver's modified state.
      Returns:
      true if the receiver is marked as modified, or false otherwise
      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:
      3.5

    • getRegion

      public Region getRegion()
      Returns the region that defines the shape of the shell, or null if the shell has the default shape.
      Overrides:
      getRegion in class Control
      Returns:
      the region that defines the shape of the shell, 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
      Since:
      3.0

    • getShell

      public Shell getShell()
      Description copied from class: Control
      Returns the receiver's shell. For all controls other than shells, this simply returns the control's nearest ancestor shell. Shells return themselves, even if they are children of other shells.
      Overrides:
      getShell in class Control
      Returns:
      the receiver's shell
      See Also:

    • getShells

      public Shell[] getShells()
      Returns an array containing all shells which are descendants 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

    • getToolBar

      public ToolBar getToolBar()
      Returns a ToolBar object representing the tool bar that can be shown in the receiver's trim. This will return null if the platform does not support tool bars that are not part of the content area of the shell, or if the Shell's style does not support having a tool bar.
      Returns:
      a ToolBar object representing the Shell's tool 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
      Since:
      3.7

    • 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:

    • 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:

    • 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:

    • print

      public boolean print(GC gc)
      Description copied from class: Control
      Prints the receiver and all children.
      Overrides:
      print in class Control
      Parameters:
      gc - the gc where the drawing occurs
      Returns:
      true if the operation was successful and false otherwise

    • removeShellListener

      public void removeShellListener(ShellListener listener)
      Removes the listener from the collection of listeners who will be notified when operations are performed on the receiver.
      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:

    • requestLayout

      public void requestLayout()
      Description copied from class: Control
      Requests that this control and all of its ancestors be repositioned by their layouts at the earliest opportunity. This should be invoked after modifying the control in order to inform any dependent layouts of the change.

      The control will not be repositioned synchronously. This method is fast-running and only marks the control for future participation in a deferred layout.

      Invoking this method multiple times before the layout occurs is an inexpensive no-op.

      Overrides:
      requestLayout in class Control

    • 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
      Since:
      2.0
      See Also:

    • setAlpha

      public void setAlpha(int alpha)
      Sets the receiver's alpha value which must be between 0 (transparent) and 255 (opaque).

      This operation requires the operating system's advanced widgets subsystem which 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:
      3.4

    • 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

    • setFullScreen

      public void setFullScreen(boolean fullScreen)
      Sets the full screen state of the receiver. If the argument is true causes the receiver to switch to the full screen state, and if the argument is false and the receiver was previously switched into full screen state, causes the receiver to switch back to either the maximized or normal states.

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

      Parameters:
      fullScreen - the new fullscreen 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
      Since:
      3.4

    • setImeInputMode

      public void setImeInputMode(int mode)
      Sets the input method editor mode to the argument which should be the result of bitwise OR'ing together one or more of the following constants defined in class SWT: NONE, ROMAN, DBCS, PHONETIC, NATIVE, ALPHA.
      Parameters:
      mode - the new IME mode
      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:

    • setMaximumSize

      public void setMaximumSize(int width, int height)
      Sets the receiver's maximum size to the size specified by the arguments. If the new maximum size is smaller than the current size of the receiver, the receiver is resized to the new maximum size.

      Note: The result of intermixing calls to setMaximumSize and setFullScreen(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:
      width - the new maximum width for the receiver
      height - the new maximum height 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:
      3.116

    • setMaximumSize

      public void setMaximumSize(Point size)
      Sets the receiver's maximum size to the size specified by the argument. If the new maximum size is smaller than the current size of the receiver, the receiver is resized to the new maximum size.

      Note: The result of intermixing calls to setMaximumSize and setFullScreen(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:
      size - the new maximum size for the receiver
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the point 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
      Since:
      3.116

    • setMinimumSize

      public void setMinimumSize(int width, int height)
      Sets the receiver's minimum size to the size specified by the arguments. If the new minimum size is larger than the current size of the receiver, the receiver is resized to the new minimum size.
      Parameters:
      width - the new minimum width for the receiver
      height - the new minimum height 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:
      3.1

    • setMinimumSize

      public void setMinimumSize(Point size)
      Sets the receiver's minimum size to the size specified by the argument. If the new minimum size is larger than the current size of the receiver, the receiver is resized to the new minimum size.
      Parameters:
      size - the new minimum size for the receiver
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the point 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
      Since:
      3.1

    • 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:
      3.5

    • setRegion

      public void setRegion(Region region)
      Sets the shape of the shell to the region specified by the argument. When the argument is null, the default shape of the shell is restored. The shell must be created with the style SWT.NO_TRIM in order to specify a region.

      NOTE: This method also sets the size of the shell. Clients should not call Control.setSize(int, int) or Control.setBounds(int, int, int, int) on this shell. Furthermore, the passed region should not be modified any more.

      Overrides:
      setRegion in class Control
      Parameters:
      region - the region that defines the shape of the shell (or null)
      Throws:
      IllegalArgumentException -
      • ERROR_INVALID_ARGUMENT - if the region 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

    • 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 Decorations
      Parameters:
      visible - the new visibility state