Class Display

java.lang.Object
org.eclipse.swt.graphics.Device
org.eclipse.swt.widgets.Display
All Implemented Interfaces:
Drawable

public class Display extends Device
Instances of this class are responsible for managing the connection between SWT and the underlying operating system. Their most important function is to implement the SWT event loop in terms of the platform event model. They also provide various methods for accessing information about the operating system, and have overall control over the operating system resources which SWT allocates.

Applications which are built with SWT will almost always require only a single display. In particular, some platforms which SWT supports will not allow more than one active display. In other words, some platforms do not support creating a new display if one already exists that has not been sent the dispose() message.

In SWT, the thread which creates a Display instance is distinguished as the user-interface thread for that display.

The user-interface thread for a particular display has the following special attributes:
  • The event loop for that display must be run from the thread.
  • Some SWT API methods (notably, most of the public methods in Widget and its subclasses), may only be called from the thread. (To support multi-threaded user-interface applications, class Display provides inter-thread communication methods which allow threads other than the user-interface thread to request that it perform operations on their behalf.)
  • The thread is not allowed to construct other Displays until that display has been disposed. (Note that, this is in addition to the restriction mentioned above concerning platform support for multiple displays. Thus, the only way to have multiple simultaneously active displays, even on platforms which support it, is to have multiple threads.)

Enforcing these attributes allows SWT to be implemented directly on the underlying operating system's event model. This has numerous benefits including smaller footprint, better use of resources, safer memory management, clearer program logic, better performance, and fewer overall operating system threads required. The down side however, is that care must be taken (only) when constructing multi-threaded applications to use the inter-thread communication mechanisms which this class provides when required.

All SWT API methods which may only be called from the user-interface thread are distinguished in their documentation by indicating that they throw the "ERROR_THREAD_INVALID_ACCESS" SWT exception.

Styles:
(none)
Events:
Close, Dispose, OpenDocument, Settings, Skin

IMPORTANT: This class is not intended to be subclassed.

See Also:
Restriction:
This class is not intended to be subclassed by clients.
  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    org.eclipse.swt.internal.win32.MSG
    the handle to the OS message queue (Warning: This field is platform dependent)

    Fields inherited from class org.eclipse.swt.graphics.Device

    CurrentDevice, DEBUG, DeviceFinder
  • Constructor Summary

    Constructors
    Constructor
    Description
    Constructs a new instance of this class.
    Constructs a new instance of this class using the parameter.
  • Method Summary

    Modifier and Type
    Method
    Description
    void
    addFilter(int eventType, Listener listener)
    Adds the listener to the collection of listeners who will be notified when an event of the given type occurs anywhere in a widget.
    void
    addListener(int eventType, Listener listener)
    Adds the listener to the collection of listeners who will be notified when an event of the given type occurs.
    void
    asyncExec(Runnable runnable)
    Causes the run() method of the runnable to be invoked by the user-interface thread at the next reasonable opportunity.
    void
    Causes the system hardware to emit a short sound (if it supports this capability).
    protected void
    Throws an SWTException if the receiver can not be accessed by the caller.
    protected void
    Checks that this class can be subclassed.
    void
    Requests that the connection between SWT and the underlying operating system be closed.
    protected void
    Creates the device in the operating system.
    protected void
    Destroys the device in the operating system and releases the device's handle.
    void
    Causes the run() method of the runnable to be invoked by the user-interface thread just before the receiver is disposed.
    static Display
    Returns the display which the given thread is the user-interface thread for, or null if the given thread is not a user-interface thread for any display.
    findWidget(long handle)
    Given the operating system handle for a widget, returns the instance of the Widget subclass which represents it in the currently running application, if such exists, or null if no matching widget can be found.
    findWidget(long handle, long id)
    Given the operating system handle for a widget, and widget-specific id, returns the instance of the Widget subclass which represents the handle/id pair in the currently running application, if such exists, or null if no matching widget can be found.
    findWidget(Widget widget, long id)
    Given a widget and a widget-specific id, returns the instance of the Widget subclass which represents the widget/id pair in the currently running application, if such exists, or null if no matching widget can be found.
    Returns the currently active Shell, or null if no shell belonging to the currently running application is active.
    static String
    Returns the application name.
    static String
    Returns the application version.
    Returns a rectangle describing the receiver's size and location.
    Returns a rectangle which describes the area of the receiver which is capable of displaying data.
    static Display
    Returns the display which the currently running thread is the user-interface thread for, or null if the currently running thread is not a user-interface thread for any display.
    Returns the control which the on-screen pointer is currently over top of, or null if it is not currently over one of the controls built by the currently running application.
    Returns the location of the on-screen pointer relative to the top left corner of the screen.
    Returns an array containing the recommended cursor sizes.
    Returns the application defined, display specific data associated with the receiver, or null if it has not been set.
    Returns the application defined property of the receiver with the specified name, or null if it has not been set.
    static Display
    Returns the default display.
    protected int
    Gets the scaling factor from the device and calculates the zoom level.
    int
    Returns the button dismissal alignment, one of LEFT or RIGHT.
    int
    Returns the longest duration, in milliseconds, between two mouse button clicks that will be considered a double click by the underlying operating system.
    Returns the current exception handler.
    Returns the control which currently has keyboard focus, or null if keyboard events are not currently going to any of the controls built by the currently running application.
    boolean
    Returns true when the high contrast mode is enabled.
    int
    Returns the maximum allowed depth of icons on this display, in bits per pixel.
    Returns an array containing the recommended icon sizes.
    Returns the single instance of the application menu bar, or null if there is no application menu bar for the platform.
    Returns an array of monitors attached to the device.
    Returns the primary monitor for that device.
    Returns the current exception handler.
    Returns a (possibly empty) array containing all shells which have not been disposed and have the receiver as their display.
    Gets the synchronizer used by the display.
    Returns the thread that has invoked syncExec or null if no such runnable is currently being invoked by the user-interface thread.
    Returns the matching standard color for the given constant, which should be one of the color constants specified in class SWT.
    Returns the matching standard platform cursor for the given constant, which should be one of the cursor constants specified in class SWT.
    Returns a reasonable font for applications to use.
    Returns the matching standard platform image for the given constant, which should be one of the icon constants specified in class SWT.
    Returns the single instance of the system-provided menu for the application, or null on platforms where no menu is provided for the application.
    Returns the single instance of the system taskBar or null when there is no system taskBar available for the platform.
    Returns the single instance of the system tray or null when there is no system tray available for the platform.
    Returns the user-interface thread for the receiver.
    boolean
    Returns a boolean indicating whether a touch-aware input device is attached to the system and is ready for use.
    protected void
    Initializes any internal resources needed by the device.
    void
    internal_dispose_GC(long hDC, GCData data)
    Invokes platform specific functionality to dispose a GC handle.
    long
    Invokes platform specific functionality to allocate a new GC handle.
    static boolean
    Returns true if the current OS theme has a dark appearance, else returns false.
    map(Control from, Control to, int x, int y)
    Maps a point from one coordinate system to another.
    map(Control from, Control to, int x, int y, int width, int height)
    Maps a point from one coordinate system to another.
    map(Control from, Control to, Point point)
    Maps a point from one coordinate system to another.
    map(Control from, Control to, Rectangle rectangle)
    Maps a point from one coordinate system to another.
    boolean
    post(Event event)
    Generate a low level system event.
    boolean
    Reads an event from the operating system's event queue, dispatches it appropriately, and returns true if there is potentially more work to do, or false if the caller can sleep until another event is placed on the event queue.
    protected void
    Releases any internal resources back to the operating system and clears all fields except the device handle.
    void
    removeFilter(int eventType, Listener listener)
    Removes the listener from the collection of listeners who will be notified when an event of the given type occurs anywhere in a widget.
    void
    removeListener(int eventType, Listener listener)
    Removes the listener from the collection of listeners who will be notified when an event of the given type occurs.
    void
    Sends a SWT.PostExternalEventDispatch event.
    void
    Sends a SWT.PreExternalEventDispatch event.
    static void
    Sets the application name to the argument.
    static void
    Sets the application version to the argument.
    void
    setCursorLocation(int x, int y)
    Sets the location of the on-screen pointer relative to the top left corner of the screen.
    void
    Sets the location of the on-screen pointer relative to the top left corner of the screen.
    void
    Sets the application defined, display specific data associated with the receiver, to the argument.
    void
    setData(String key, Object value)
    Sets the application defined property of the receiver with the specified name to the given argument.
    final void
    Sets a callback that will be invoked whenever an error is thrown by a listener or external callback function.
    final void
    Sets a callback that will be invoked whenever an exception is thrown by a listener or external callback function.
    void
    Sets the synchronizer used by the display to be the argument, which can not be null.
    boolean
    Causes the user-interface thread to sleep (that is, to be put in a state where it does not consume CPU cycles) until an event is received or it is otherwise awakened.
    <T, E extends Exception>
    T
    syncCall(SwtCallable<T,E> callable)
    Calls the callable on the user-interface thread at the next reasonable opportunity, and returns the its result from this method.
    void
    syncExec(Runnable runnable)
    Causes the run() method of the runnable to be invoked by the user-interface thread at the next reasonable opportunity.
    void
    timerExec(int milliseconds, Runnable runnable)
    Causes the run() method of the runnable to be invoked by the user-interface thread after the specified number of milliseconds have elapsed.
    void
    Forces all outstanding paint requests for the display to be processed before this method returns.
    void
    If the receiver's user-interface thread was sleeping, causes it to be awakened and start running again.

    Methods inherited from class org.eclipse.swt.graphics.Device

    dispose, getDepth, getDeviceData, getDPI, getFontList, getWarnings, isDisposed, isTracking, loadFont, setTracking, setWarnings

    Methods inherited from class java.lang.Object

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

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

    isAutoScalable
  • Field Details

    • msg

      public org.eclipse.swt.internal.win32.MSG msg
      the handle to the OS message queue (Warning: This field is platform dependent)

      IMPORTANT: This field is not part of the SWT public API. 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 accessed from application code.

      Restriction:
      This field is not intended to be referenced by clients.
  • Constructor Details

    • Display

      public Display()
      Constructs a new instance of this class.

      Note: The resulting display is marked as the current display. If this is the first display which has been constructed since the application started, it is also marked as the default display.

      Throws:
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if called from a thread that already created an existing display
      • ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass
      See Also:
    • Display

      public Display(DeviceData data)
      Constructs a new instance of this class using the parameter.
      Parameters:
      data - the device data
  • Method Details

    • addFilter

      public void addFilter(int eventType, Listener listener)
      Adds the listener to the collection of listeners who will be notified when an event of the given type occurs anywhere in a widget. The event type is one of the event constants defined in class SWT. When the event does occur, the listener is notified by sending it the handleEvent() message.

      Setting the type of an event to SWT.None from within the handleEvent() method can be used to change the event type and stop subsequent Java listeners from running. Because event filters run before other listeners, event filters can both block other listeners and set arbitrary fields within an event. For this reason, event filters are both powerful and dangerous. They should generally be avoided for performance, debugging and code maintenance reasons.

      Parameters:
      eventType - the type of event to listen for
      listener - the listener which should be notified when the event occurs
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the listener is null
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      Since:
      3.0
      See Also:
    • addListener

      public void addListener(int eventType, Listener listener)
      Adds the listener to the collection of listeners who will be notified when an event of the given type occurs. The event type is one of the event constants defined in class SWT. When the event does occur in the display, the listener is notified by sending it the handleEvent() message.
      Parameters:
      eventType - the type of event to listen for
      listener - the listener which should be notified when the event occurs
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the listener is null
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      Since:
      2.0
      See Also:
    • asyncExec

      public void asyncExec(Runnable runnable)
      Causes the run() method of the runnable to be invoked by the user-interface thread at the next reasonable opportunity. The caller of this method continues to run in parallel, and is not notified when the runnable has completed. Specifying null as the runnable simply wakes the user-interface thread when run.

      Note that at the time the runnable is invoked, widgets that have the receiver as their display may have been disposed. Therefore, it is necessary to check for this case inside the runnable before accessing the widget.

      Parameters:
      runnable - code to run on the user-interface thread or null
      Throws:
      SWTException -
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      See Also:
    • beep

      public void beep()
      Causes the system hardware to emit a short sound (if it supports this capability).
      Throws:
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
    • checkSubclass

      protected void checkSubclass()
      Checks that this class can be subclassed.

      IMPORTANT: See the comment in Widget.checkSubclass().

      Throws:
      SWTException -
      • ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass
      See Also:
    • checkDevice

      protected void checkDevice()
      Description copied from class: Device
      Throws an SWTException if the receiver can not be accessed by the caller. This may include both checks on the state of the receiver and more generally on the entire execution context. This method should be called by device implementors to enforce the standard SWT invariants.

      Currently, it is an error to invoke any method (other than isDisposed() and dispose()) on a device that has had its dispose() method called.

      In future releases of SWT, there may be more or fewer error checks and exceptions may be thrown for different reasons.

      Overrides:
      checkDevice in class Device
    • close

      public void close()
      Requests that the connection between SWT and the underlying operating system be closed.
      Throws:
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      Since:
      2.0
      See Also:
    • create

      protected void create(DeviceData data)
      Creates the device in the operating system. If the device does not have a handle, this method may do nothing depending on the device.

      This method is called before init.

      Overrides:
      create in class Device
      Parameters:
      data - the DeviceData which describes the receiver
      See Also:
    • destroy

      protected void destroy()
      Destroys the device in the operating system and releases the device's handle. If the device does not have a handle, this method may do nothing depending on the device.

      This method is called after release.

      Overrides:
      destroy in class Device
      See Also:
    • disposeExec

      public void disposeExec(Runnable runnable)
      Causes the run() method of the runnable to be invoked by the user-interface thread just before the receiver is disposed. Specifying a null runnable is ignored.
      Parameters:
      runnable - code to run at dispose time.
      Throws:
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
    • findWidget

      public Widget findWidget(long handle)
      Given the operating system handle for a widget, returns the instance of the Widget subclass which represents it in the currently running application, if such exists, or null if no matching widget can be found.

      IMPORTANT: This method should not be called from application code. The arguments are platform-specific.

      Parameters:
      handle - the handle for the widget
      Returns:
      the SWT widget that the handle represents
      Throws:
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      Restriction:
      This method is not intended to be referenced by clients.
    • findWidget

      public Widget findWidget(long handle, long id)
      Given the operating system handle for a widget, and widget-specific id, returns the instance of the Widget subclass which represents the handle/id pair in the currently running application, if such exists, or null if no matching widget can be found.

      IMPORTANT: This method should not be called from application code. The arguments are platform-specific.

      Parameters:
      handle - the handle for the widget
      id - the id for the subwidget (usually an item)
      Returns:
      the SWT widget that the handle/id pair represents
      Throws:
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      Since:
      3.1
      Restriction:
      This method is not intended to be referenced by clients.
    • findWidget

      public Widget findWidget(Widget widget, long id)
      Given a widget and a widget-specific id, returns the instance of the Widget subclass which represents the widget/id pair in the currently running application, if such exists, or null if no matching widget can be found.
      Parameters:
      widget - the widget
      id - the id for the subwidget (usually an item)
      Returns:
      the SWT subwidget (usually an item) that the widget/id pair represents
      Throws:
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      Since:
      3.3
      Restriction:
      This method is not intended to be referenced by clients.
    • findDisplay

      public static Display findDisplay(Thread thread)
      Returns the display which the given thread is the user-interface thread for, or null if the given thread is not a user-interface thread for any display. Specifying null as the thread will return null for the display.
      Parameters:
      thread - the user-interface thread
      Returns:
      the display for the given thread
    • getActiveShell

      public Shell getActiveShell()
      Returns the currently active Shell, or null if no shell belonging to the currently running application is active.
      Returns:
      the active shell or null
      Throws:
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
    • getMenuBar

      public Menu getMenuBar()
      Returns the single instance of the application menu bar, or null if there is no application menu bar for the platform.
      Returns:
      the application menu bar, or null
      Throws:
      SWTException -
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      Since:
      3.7
    • getBounds

      public Rectangle getBounds()
      Returns a rectangle describing the receiver's size and location. Note that on multi-monitor systems the origin can be negative.
      Overrides:
      getBounds in class Device
      Returns:
      the bounding rectangle
      Throws:
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
    • getCurrent

      public static Display getCurrent()
      Returns the display which the currently running thread is the user-interface thread for, or null if the currently running thread is not a user-interface thread for any display.
      Returns:
      the current display
    • getClientArea

      public Rectangle getClientArea()
      Returns a rectangle which describes the area of the receiver which is capable of displaying data.
      Overrides:
      getClientArea in class Device
      Returns:
      the client area
      Throws:
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      See Also:
    • getCursorControl

      public Control getCursorControl()
      Returns the control which the on-screen pointer is currently over top of, or null if it is not currently over one of the controls built by the currently running application.
      Returns:
      the control under the cursor or null
      Throws:
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
    • getCursorLocation

      public Point getCursorLocation()
      Returns the location of the on-screen pointer relative to the top left corner of the screen.
      Returns:
      the cursor location
      Throws:
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
    • getCursorSizes

      public Point[] getCursorSizes()
      Returns an array containing the recommended cursor sizes.
      Returns:
      the array of cursor sizes
      Throws:
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      Since:
      3.0
    • getDefault

      public static Display getDefault()
      Returns the default display. One is created (making the thread that invokes this method its user-interface thread) if it did not already exist.
      Returns:
      the default display
    • getDeviceZoom

      protected int getDeviceZoom()
      Description copied from class: Device
      Gets the scaling factor from the device and calculates the zoom level.
      Overrides:
      getDeviceZoom in class Device
      Returns:
      zoom in percentage
      Since:
      3.108
    • getData

      public Object getData(String key)
      Returns the application defined property of the receiver with the specified name, or null if it has not been set.

      Applications may have associated arbitrary objects with the receiver in this fashion. If the objects stored in the properties need to be notified when the display is disposed of, it is the application's responsibility to provide a disposeExec() handler which does so.

      Parameters:
      key - the name of the property
      Returns:
      the value of the property or null if it has not been set
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the key is null
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      See Also:
    • getData

      public Object getData()
      Returns the application defined, display specific data associated with the receiver, or null if it has not been set. The display specific data is a single, unnamed field that is stored with every display.

      Applications may put arbitrary objects in this field. If the object stored in the display specific data needs to be notified when the display is disposed of, it is the application's responsibility to provide a disposeExec() handler which does so.

      Returns:
      the display specific data
      Throws:
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      See Also:
    • getDismissalAlignment

      public int getDismissalAlignment()
      Returns the button dismissal alignment, one of LEFT or RIGHT. The button dismissal alignment is the ordering that should be used when positioning the default dismissal button for a dialog. For example, in a dialog that contains an OK and CANCEL button, on platforms where the button dismissal alignment is LEFT, the button ordering should be OK/CANCEL. When button dismissal alignment is RIGHT, the button ordering should be CANCEL/OK.
      Returns:
      the button dismissal order
      Throws:
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      Since:
      2.1
    • getDoubleClickTime

      public int getDoubleClickTime()
      Returns the longest duration, in milliseconds, between two mouse button clicks that will be considered a double click by the underlying operating system.
      Returns:
      the double click time
      Throws:
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
    • getFocusControl

      public Control getFocusControl()
      Returns the control which currently has keyboard focus, or null if keyboard events are not currently going to any of the controls built by the currently running application.
      Returns:
      the focus control or null
      Throws:
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
    • getHighContrast

      public boolean getHighContrast()
      Returns true when the high contrast mode is enabled. Otherwise, false is returned.

      Note: This operation is a hint and is not supported on platforms that do not have this concept.

      Returns:
      the high contrast mode
      Throws:
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      Since:
      3.0
    • getIconDepth

      public int getIconDepth()
      Returns the maximum allowed depth of icons on this display, in bits per pixel. On some platforms, this may be different than the actual depth of the display.
      Returns:
      the maximum icon depth
      Throws:
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      See Also:
    • getIconSizes

      public Point[] getIconSizes()
      Returns an array containing the recommended icon sizes.
      Returns:
      the array of icon sizes
      Throws:
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      Since:
      3.0
      See Also:
    • isSystemDarkTheme

      public static boolean isSystemDarkTheme()
      Returns true if the current OS theme has a dark appearance, else returns false.

      Note: This operation is a hint and is not supported on platforms that do not have this concept.

      Note: Windows 10 onwards users can separately configure the theme for OS and Application level and this can be read from the Windows registry. Since the application needs to honor the application level theme, this API reads the Application level theme setting.

      Returns:
      true if the current OS theme has a dark appearance, else returns false.
      Since:
      3.112
    • getMonitors

      public Monitor[] getMonitors()
      Returns an array of monitors attached to the device.
      Returns:
      the array of monitors
      Since:
      3.0
    • getPrimaryMonitor

      public Monitor getPrimaryMonitor()
      Returns the primary monitor for that device.
      Returns:
      the primary monitor
      Since:
      3.0
    • getShells

      public Shell[] getShells()
      Returns a (possibly empty) array containing all shells which have not been disposed and have the receiver as their display.
      Returns:
      the receiver's shells
      Throws:
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
    • getSynchronizer

      public Synchronizer getSynchronizer()
      Gets the synchronizer used by the display.
      Returns:
      the receiver's synchronizer
      Throws:
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      Since:
      3.4
    • getSyncThread

      public Thread getSyncThread()
      Returns the thread that has invoked syncExec or null if no such runnable is currently being invoked by the user-interface thread.

      Note: If a runnable invoked by asyncExec is currently running, this method will return null.

      Returns:
      the receiver's sync-interface thread
      Throws:
      SWTException -
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
    • getSystemColor

      public Color getSystemColor(int id)
      Returns the matching standard color for the given constant, which should be one of the color constants specified in class SWT. Any value other than one of the SWT color constants which is passed in will result in the color black. This color should not be free'd because it was allocated by the system, not the application.
      Overrides:
      getSystemColor in class Device
      Parameters:
      id - the color constant
      Returns:
      the matching color
      Throws:
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      See Also:
    • getSystemCursor

      public Cursor getSystemCursor(int id)
      Returns the matching standard platform cursor for the given constant, which should be one of the cursor constants specified in class SWT. This cursor should not be free'd because it was allocated by the system, not the application. A value of null will be returned if the supplied constant is not an SWT cursor constant.
      Parameters:
      id - the SWT cursor constant
      Returns:
      the corresponding cursor or null
      Throws:
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      Since:
      3.0
      See Also:
    • getSystemFont

      public Font getSystemFont()
      Returns a reasonable font for applications to use. On some platforms, this will match the "default font" or "system font" if such can be found. This font should not be free'd because it was allocated by the system, not the application.

      Typically, applications which want the default look should simply not set the font on the widgets they create. Widgets are always created with the correct default font for the class of user-interface component they represent.

      Overrides:
      getSystemFont in class Device
      Returns:
      a font
      Throws:
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
    • getSystemImage

      public Image getSystemImage(int id)
      Returns the matching standard platform image for the given constant, which should be one of the icon constants specified in class SWT. This image should not be free'd because it was allocated by the system, not the application. A value of null will be returned either if the supplied constant is not an SWT icon constant or if the platform does not define an image that corresponds to the constant.
      Parameters:
      id - the SWT icon constant
      Returns:
      the corresponding image or null
      Throws:
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      Since:
      3.0
      See Also:
    • getSystemMenu

      public Menu getSystemMenu()
      Returns the single instance of the system-provided menu for the application, or null on platforms where no menu is provided for the application.
      Returns:
      the system menu, or null
      Throws:
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      Since:
      3.7
    • getSystemTaskBar

      public TaskBar getSystemTaskBar()
      Returns the single instance of the system taskBar or null when there is no system taskBar available for the platform.
      Returns:
      the system taskBar or null
      Throws:
      SWTException -
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      Since:
      3.6
    • getSystemTray

      public Tray getSystemTray()
      Returns the single instance of the system tray or null when there is no system tray available for the platform.
      Returns:
      the system tray or null
      Throws:
      SWTException -
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      Since:
      3.0
    • getThread

      public Thread getThread()
      Returns the user-interface thread for the receiver.
      Returns:
      the receiver's user-interface thread
      Throws:
      SWTException -
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
    • getTouchEnabled

      public boolean getTouchEnabled()
      Returns a boolean indicating whether a touch-aware input device is attached to the system and is ready for use.
      Returns:
      true if a touch-aware input device is detected, or false otherwise
      Throws:
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      Since:
      3.7
    • internal_new_GC

      public long internal_new_GC(GCData data)
      Invokes platform specific functionality to allocate a new GC handle.

      IMPORTANT: This method is not part of the public API for Display. 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.

      Specified by:
      internal_new_GC in interface Drawable
      Specified by:
      internal_new_GC in class Device
      Parameters:
      data - the platform specific GC data
      Returns:
      the platform specific GC handle
      Throws:
      SWTException -
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      SWTError -
      • ERROR_NO_HANDLES if a handle could not be obtained for gc creation
      Restriction:
      This method is not intended to be referenced by clients.
    • init

      protected void init()
      Initializes any internal resources needed by the device.

      This method is called after create.

      Overrides:
      init in class Device
      See Also:
    • internal_dispose_GC

      public void internal_dispose_GC(long hDC, GCData data)
      Invokes platform specific functionality to dispose a GC handle.

      IMPORTANT: This method is not part of the public API for Display. 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.

      Specified by:
      internal_dispose_GC in interface Drawable
      Specified by:
      internal_dispose_GC in class Device
      Parameters:
      hDC - the platform specific GC handle
      data - the platform specific GC data
      Restriction:
      This method is not intended to be referenced by clients.
    • map

      public Point map(Control from, Control to, Point point)
      Maps a point from one coordinate system to another. When the control is null, coordinates are mapped to the display.

      NOTE: On right-to-left platforms where the coordinate systems are mirrored, special care needs to be taken when mapping coordinates from one control to another to ensure the result is correctly mirrored. Mapping a point that is the origin of a rectangle and then adding the width and height is not equivalent to mapping the rectangle. When one control is mirrored and the other is not, adding the width and height to a point that was mapped causes the rectangle to extend in the wrong direction. Mapping the entire rectangle instead of just one point causes both the origin and the corner of the rectangle to be mapped.

      Parameters:
      from - the source Control or null
      to - the destination Control or null
      point - to be mapped
      Returns:
      point with mapped coordinates
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the point is null
      • ERROR_INVALID_ARGUMENT - if the Control from or the Control to have been disposed
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      Since:
      2.1.2
    • map

      public Point map(Control from, Control to, int x, int y)
      Maps a point from one coordinate system to another. When the control is null, coordinates are mapped to the display.

      NOTE: On right-to-left platforms where the coordinate systems are mirrored, special care needs to be taken when mapping coordinates from one control to another to ensure the result is correctly mirrored. Mapping a point that is the origin of a rectangle and then adding the width and height is not equivalent to mapping the rectangle. When one control is mirrored and the other is not, adding the width and height to a point that was mapped causes the rectangle to extend in the wrong direction. Mapping the entire rectangle instead of just one point causes both the origin and the corner of the rectangle to be mapped.

      Parameters:
      from - the source Control or null
      to - the destination Control or null
      x - coordinates to be mapped
      y - coordinates to be mapped
      Returns:
      point with mapped coordinates
      Throws:
      IllegalArgumentException -
      • ERROR_INVALID_ARGUMENT - if the Control from or the Control to have been disposed
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      Since:
      2.1.2
    • map

      public Rectangle map(Control from, Control to, Rectangle rectangle)
      Maps a point from one coordinate system to another. When the control is null, coordinates are mapped to the display.

      NOTE: On right-to-left platforms where the coordinate systems are mirrored, special care needs to be taken when mapping coordinates from one control to another to ensure the result is correctly mirrored. Mapping a point that is the origin of a rectangle and then adding the width and height is not equivalent to mapping the rectangle. When one control is mirrored and the other is not, adding the width and height to a point that was mapped causes the rectangle to extend in the wrong direction. Mapping the entire rectangle instead of just one point causes both the origin and the corner of the rectangle to be mapped.

      Parameters:
      from - the source Control or null
      to - the destination Control or null
      rectangle - to be mapped
      Returns:
      rectangle with mapped coordinates
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the rectangle is null
      • ERROR_INVALID_ARGUMENT - if the Control from or the Control to have been disposed
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      Since:
      2.1.2
    • map

      public Rectangle map(Control from, Control to, int x, int y, int width, int height)
      Maps a point from one coordinate system to another. When the control is null, coordinates are mapped to the display.

      NOTE: On right-to-left platforms where the coordinate systems are mirrored, special care needs to be taken when mapping coordinates from one control to another to ensure the result is correctly mirrored. Mapping a point that is the origin of a rectangle and then adding the width and height is not equivalent to mapping the rectangle. When one control is mirrored and the other is not, adding the width and height to a point that was mapped causes the rectangle to extend in the wrong direction. Mapping the entire rectangle instead of just one point causes both the origin and the corner of the rectangle to be mapped.

      Parameters:
      from - the source Control or null
      to - the destination Control or null
      x - coordinates to be mapped
      y - coordinates to be mapped
      width - coordinates to be mapped
      height - coordinates to be mapped
      Returns:
      rectangle with mapped coordinates
      Throws:
      IllegalArgumentException -
      • ERROR_INVALID_ARGUMENT - if the Control from or the Control to have been disposed
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      Since:
      2.1.2
    • post

      public boolean post(Event event)
      Generate a low level system event. post is used to generate low level keyboard and mouse events. The intent is to enable automated UI testing by simulating the input from the user. Most SWT applications should never need to call this method.

      Note that this operation can fail when the operating system fails to generate the event for any reason. For example, this can happen when there is no such key or mouse button or when the system event queue is full.

      Event Types:

      KeyDown, KeyUp

      The following fields in the Event apply:

      • (in) type KeyDown or KeyUp

      Either one of:

      • (in) character a character that corresponds to a keyboard key
      • (in) keyCode the key code of the key that was typed, as defined by the key code constants in class SWT

      Optional (on some platforms):

      • (in) stateMask the state of the keyboard modifier, as defined by the key code constants in class SWT

      MouseDown, MouseUp

      The following fields in the Event apply:

      • (in) type MouseDown or MouseUp
      • (in) button the button that is pressed or released

      MouseMove

      The following fields in the Event apply:

      • (in) type MouseMove
      • (in) x the x coordinate to move the mouse pointer to in screen coordinates
      • (in) y the y coordinate to move the mouse pointer to in screen coordinates

      MouseWheel

      The following fields in the Event apply:

      • (in) type MouseWheel
      • (in) detail either SWT.SCROLL_LINE or SWT.SCROLL_PAGE
      • (in) count the number of lines or pages to scroll
      Parameters:
      event - the event to be generated
      Returns:
      true if the event was generated or false otherwise
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the event is null
      SWTException -
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      Since:
      3.0
    • readAndDispatch

      public boolean readAndDispatch()
      Reads an event from the operating system's event queue, dispatches it appropriately, and returns true if there is potentially more work to do, or false if the caller can sleep until another event is placed on the event queue.

      In addition to checking the system event queue, this method also checks if any inter-thread messages (created by syncExec() or asyncExec()) are waiting to be processed, and if so handles them before returning.

      Returns:
      false if the caller can sleep upon return from this method
      Throws:
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      • ERROR_FAILED_EXEC - if an exception occurred while running an inter-thread message
      See Also:
    • release

      protected void release()
      Releases any internal resources back to the operating system and clears all fields except the device handle.

      Disposes all shells which are currently open on the display. After this method has been invoked, all related related shells will answer true when sent the message isDisposed().

      When a device is destroyed, resources that were acquired on behalf of the programmer need to be returned to the operating system. For example, if the device allocated a font to be used as the system font, this font would be freed in release. Also,to assist the garbage collector and minimize the amount of memory that is not reclaimed when the programmer keeps a reference to a disposed device, all fields except the handle are zero'd. The handle is needed by destroy.

      This method is called before destroy.
      Overrides:
      release in class Device
      See Also:
    • removeFilter

      public void removeFilter(int eventType, Listener listener)
      Removes the listener from the collection of listeners who will be notified when an event of the given type occurs anywhere in a widget. The event type is one of the event constants defined in class SWT.
      Parameters:
      eventType - the type of event to listen for
      listener - the listener which should no longer be notified when the event occurs
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the listener is null
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      Since:
      3.0
      See Also:
    • removeListener

      public void removeListener(int eventType, Listener listener)
      Removes the listener from the collection of listeners who will be notified when an event of the given type occurs. The event type is one of the event constants defined in class SWT.
      Parameters:
      eventType - the type of event to listen for
      listener - the listener which should no longer be notified
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the listener is null
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      Since:
      2.0
      See Also:
    • sendPreExternalEventDispatchEvent

      public void sendPreExternalEventDispatchEvent()
      Sends a SWT.PreExternalEventDispatch event.
      Restriction:
      This method is not intended to be referenced by clients.
    • sendPostExternalEventDispatchEvent

      public void sendPostExternalEventDispatchEvent()
      Sends a SWT.PostExternalEventDispatch event.
      Restriction:
      This method is not intended to be referenced by clients.
    • setCursorLocation

      public void setCursorLocation(int x, int y)
      Sets the location of the on-screen pointer relative to the top left corner of the screen. Note: It is typically considered bad practice for a program to move the on-screen pointer location.
      Parameters:
      x - the new x coordinate for the cursor
      y - the new y coordinate for the cursor
      Throws:
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      Since:
      2.1
    • setCursorLocation

      public void setCursorLocation(Point point)
      Sets the location of the on-screen pointer relative to the top left corner of the screen. Note: It is typically considered bad practice for a program to move the on-screen pointer location.
      Parameters:
      point - new position
      Throws:
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_NULL_ARGUMENT - if the point is null
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      Since:
      2.0
    • setData

      public void setData(String key, Object value)
      Sets the application defined property of the receiver with the specified name to the given argument.

      Applications may have associated arbitrary objects with the receiver in this fashion. If the objects stored in the properties need to be notified when the display is disposed of, it is the application's responsibility provide a disposeExec() handler which does so.

      Parameters:
      key - the name of the property
      value - the new value for the property
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the key is null
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      See Also:
    • setData

      public void setData(Object data)
      Sets the application defined, display specific data associated with the receiver, to the argument. The display specific data is a single, unnamed field that is stored with every display.

      Applications may put arbitrary objects in this field. If the object stored in the display specific data needs to be notified when the display is disposed of, it is the application's responsibility provide a disposeExec() handler which does so.

      Parameters:
      data - the new display specific data
      Throws:
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      See Also:
    • getAppName

      public static String getAppName()
      Returns the application name.
      Returns:
      the application name
      Since:
      3.6
      See Also:
    • getAppVersion

      public static String getAppVersion()
      Returns the application version.
      Returns:
      the application version
      Since:
      3.6
      See Also:
    • setAppName

      public static void setAppName(String name)
      Sets the application name to the argument.

      The application name can be used in several ways, depending on the platform and tools being used. Accessibility tools could ask for the application name. On Windows, if the application name is set to any value other than "SWT" (case insensitive), it is used to set the application user model ID which is used by the OS for taskbar grouping.

      Specifying null for the name clears it.

      Parameters:
      name - the new app name or null
      See Also:
    • setAppVersion

      public static void setAppVersion(String version)
      Sets the application version to the argument.
      Parameters:
      version - the new app version
      Since:
      3.6
    • setSynchronizer

      public void setSynchronizer(Synchronizer synchronizer)
      Sets the synchronizer used by the display to be the argument, which can not be null.
      Parameters:
      synchronizer - the new synchronizer for the display (must not be null)
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the synchronizer is null
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      • ERROR_FAILED_EXEC - if an exception occurred while running an inter-thread message
    • setRuntimeExceptionHandler

      public final void setRuntimeExceptionHandler(Consumer<RuntimeException> runtimeExceptionHandler)
      Sets a callback that will be invoked whenever an exception is thrown by a listener or external callback function. The application may use this to set a global exception handling policy: the most common policies are either to log and discard the exception or to re-throw the exception.

      The default SWT error handling policy is to rethrow exceptions.

      Parameters:
      runtimeExceptionHandler - new exception handler to be registered.
      Since:
      3.106
    • getRuntimeExceptionHandler

      public final Consumer<RuntimeException> getRuntimeExceptionHandler()
      Returns the current exception handler. It will receive all exceptions thrown by listeners and external callbacks in this display. If code wishes to temporarily replace the exception handler (for example, during a unit test), it is common practice to invoke this method prior to replacing the exception handler so that the old handler may be restored afterward.
      Returns:
      the current exception handler. Never null.
      Since:
      3.106
    • setErrorHandler

      public final void setErrorHandler(Consumer<Error> errorHandler)
      Sets a callback that will be invoked whenever an error is thrown by a listener or external callback function. The application may use this to set a global exception handling policy: the most common policies are either to log and discard the exception or to re-throw the exception.

      The default SWT error handling policy is to rethrow exceptions.

      Parameters:
      errorHandler - new error handler to be registered.
      Since:
      3.106
    • getErrorHandler

      public final Consumer<Error> getErrorHandler()
      Returns the current exception handler. It will receive all errors thrown by listeners and external callbacks in this display. If code wishes to temporarily replace the error handler (for example, during a unit test), it is common practice to invoke this method prior to replacing the error handler so that the old handler may be restored afterward.
      Returns:
      the current error handler. Never null.
      Since:
      3.106
    • sleep

      public boolean sleep()
      Causes the user-interface thread to sleep (that is, to be put in a state where it does not consume CPU cycles) until an event is received or it is otherwise awakened.
      Returns:
      true if an event requiring dispatching was placed on the queue.
      Throws:
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      See Also:
    • syncExec

      public void syncExec(Runnable runnable)
      Causes the run() method of the runnable to be invoked by the user-interface thread at the next reasonable opportunity. The thread which calls this method is suspended until the runnable completes. Specifying null as the runnable simply wakes the user-interface thread.

      Note that at the time the runnable is invoked, widgets that have the receiver as their display may have been disposed. Therefore, it is necessary to check for this case inside the runnable before accessing the widget.

      Parameters:
      runnable - code to run on the user-interface thread or null
      Throws:
      SWTException -
      • ERROR_FAILED_EXEC - if an exception occurred when executing the runnable
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      See Also:
    • syncCall

      public <T, E extends Exception> T syncCall(SwtCallable<T,E> callable) throws E
      Calls the callable on the user-interface thread at the next reasonable opportunity, and returns the its result from this method. The thread which calls this method is suspended until the callable completes.

      Note that at the time the callable is invoked, widgets that have the receiver as their display may have been disposed. Therefore, it is necessary to check for this case inside the callable before accessing the widget.

      Any exception that is thrown from the callable is re-thrown in the calling thread. Note: The exception retains its original stack trace from the throwing thread. The call to syncCall will not be present in the stack trace.

      Parameters:
      callable - the code to call on the user-interface thread
      Throws:
      SWTException - ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      E - An exception that is thrown by the callable on the user-interface thread, and re-thrown on the calling thread
      Since:
      3.118
      See Also:
    • timerExec

      public void timerExec(int milliseconds, Runnable runnable)
      Causes the run() method of the runnable to be invoked by the user-interface thread after the specified number of milliseconds have elapsed. If milliseconds is less than zero, the runnable is not executed.

      Note that at the time the runnable is invoked, widgets that have the receiver as their display may have been disposed. Therefore, it is necessary to check for this case inside the runnable before accessing the widget.

      Parameters:
      milliseconds - the delay before running the runnable
      runnable - code to run on the user-interface thread
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the runnable is null
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      See Also:
    • update

      public void update()
      Forces all outstanding paint requests for the display to be processed before this method returns.
      Throws:
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      See Also:
    • wake

      public void wake()
      If the receiver's user-interface thread was sleeping, causes it to be awakened and start running again. Note that this method may be called from any thread.
      Throws:
      SWTException -
      • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
      See Also: