org.eclipse.swt.widgets

Class TaskItem

java.lang.Object

org.eclipse.swt.widgets.Widget

org.eclipse.swt.widgets.Item

org.eclipse.swt.widgets.TaskItem

public class TaskItem
extends Item

Instances of this class represent a task item.

Styles:

(none)

Events:

(none)

Since:

3.6

See Also:

Sample code and further information

Method Summary

Modifier and Type	Method and Description
protected void	checkSubclass() Checks that this class can be subclassed.
Menu	getMenu() Returns the receiver's pop up menu if it has one, or null if it does not.
Image	getOverlayImage() Returns the receiver's overlay image if it has one, or null if it does not.
String	getOverlayText() Returns the receiver's overlay text, which will be an empty string if it has never been set.
TaskBar	getParent() Returns the receiver's parent, which must be a TaskBar.
int	getProgress() Returns the receiver's progress.
int	getProgressState() Returns the receiver's progress state.
void	setMenu(Menu menu) Sets the receiver's pop up menu to the argument.
void	setOverlayImage(Image overlayImage) Sets the receiver's overlay image, which may be null indicating that no image should be displayed.
void	setOverlayText(String overlayText) Sets the receiver's overlay text.
void	setProgress(int progress) Sets the receiver's progress, the progress represents a percentage and should be in range from 0 to 100.
void	setProgressState(int progressState) Sets the receiver's progress state, the state can be one of the following:

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

getImage, getText, setImage, setText

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

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

Methods inherited from class java.lang.Object

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

Method Detail

checkSubclass

protected void checkSubclass()

Description copied from class: Widget

Checks that this class can be subclassed.

The SWT class library is intended to be subclassed only at specific, controlled points (most notably, Composite and Canvas when implementing new widgets). This method enforces this rule unless it is overridden.

IMPORTANT: By providing an implementation of this method that allows a subclass of a class which does not normally allow subclassing to be created, the implementer agrees to be fully responsible for the fact that any such subclass will likely fail between SWT releases and will be strongly platform specific. No support is provided for user-written classes which are implemented in this fashion.

The ability to subclass outside of the allowed SWT classes is intended purely to enable those not on the SWT development team to implement patches in order to get around specific limitations in advance of when those limitations can be addressed by the team. Subclassing should not be attempted without an intimate and detailed understanding of the hierarchy.

Overrides:

checkSubclass in class Item

getMenu

public Menu getMenu()

Returns the receiver's pop up menu if it has one, or null if it does not.

Returns:

the receiver's menu

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

getOverlayImage

public Image getOverlayImage()

Returns the receiver's overlay image if it has one, or null if it does not.

Returns:

the receiver's overlay image

Throws:

SWTException -

• ERROR_WIDGET_DISPOSED - if the receiver has been disposed
• ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver

getOverlayText

public String getOverlayText()

Returns the receiver's overlay text, which will be an empty string if it has never been set.

Returns:

the receiver's overlay text

Throws:

SWTException -

• ERROR_WIDGET_DISPOSED - if the receiver has been disposed
• ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver

getParent

public TaskBar getParent()

Returns the receiver's parent, which must be a TaskBar.

Returns:

the receiver's parent

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

getProgress

public int getProgress()

Returns the receiver's progress.

Returns:

the receiver's progress

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

getProgressState

public int getProgressState()

Returns the receiver's progress state.

Returns:

the receiver's progress 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

setMenu

public void setMenu(Menu menu)

Sets the receiver's pop up menu to the argument. The way the menu is shown is platform specific.

This feature might not be available for the receiver on all platforms. The application code can check if it is supported by calling the respective get method. When the feature is not available, the get method will always return the NULL.

For better cross platform support, the application code should set this feature on the TaskItem for application.
On Windows, this feature will only work on RCP applications.

The menu should be fully created before this method is called. Dynamic changes to the menu after the method is called will not be reflected in the native menu.

Parameters:

menu - the new pop up menu

Throws:

IllegalArgumentException -

• ERROR_MENU_NOT_POP_UP - the menu is not a pop up menu
• ERROR_INVALID_ARGUMENT - if the menu 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

setOverlayImage

public void setOverlayImage(Image overlayImage)

Sets the receiver's overlay image, which may be null indicating that no image should be displayed. The bounds for the overlay image is determined by the platform and in general it should be a small image.

This feature might not be available for the receiver on all platforms. The application code can check if it is supported by calling the respective get method. When the feature is not available, the get method will always return the NULL.

For better cross platform support, the application code should first try to set this feature on the TaskItem for the main shell then on the TaskItem for the application.

Parameters:

overlayImage - the new overlay image (may be null)

Throws:

IllegalArgumentException -

• ERROR_INVALID_ARGUMENT - if the overlayImage 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

setOverlayText

public void setOverlayText(String overlayText)

Sets the receiver's overlay text. The space available to display the overlay text is platform dependent and in general it should be no longer than a few characters.

This feature might not be available for the receiver on all platforms. The application code can check if it is supported by calling the respective get method. When the feature is not available, the get method will always return an empty string.

For better cross platform support, the application code should first try to set this feature on the TaskItem for the main shell then on the TaskItem for the application.

Parameters:

overlayText - the new overlay text

Throws:

IllegalArgumentException -

• ERROR_NULL_ARGUMENT - if the overlayText 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

setProgress

public void setProgress(int progress)

Sets the receiver's progress, the progress represents a percentage and should be in range from 0 to 100. The progress is only shown when the progress state is different than SWT#DEFAULT.

This feature might not be available for the receiver on all platforms. The application code can check if it is supported by calling the respective get method. When the feature is not available, the get method will always return zero.

For better cross platform support, the application code should first try to set this feature on the TaskItem for the main shell then on the TaskItem for the application.

Parameters:

progress - the new progress

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 setProgressState(int)

setProgressState

public void setProgressState(int progressState)

Sets the receiver's progress state, the state can be one of the following:

• SWT.DEFAULT
• SWT.NORMAL
• SWT.PAUSED
• SWT.ERROR
• SWT.INDETERMINATE

The percentage of progress shown by the states SWT#NORMAL, SWT#PAUSED, SWT#ERROR is set with setProgress().
The state SWT#DEFAULT indicates that no progress should be shown.

This feature might not be available for the receiver on all platforms. The application code can check if it is supported by calling the respective get method. When the feature is not available, the get method will always return SWT#DEFAULT.

For better cross platform support, the application code should first try to set this feature on the TaskItem for the main shell then on the TaskItem for the application.

Parameters:

progressState - the new progress state

Throws:

SWTException -

• ERROR_WIDGET_DISPOSED - if the receiver has been disposed
• ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver

#see setProgress(int)