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org.eclipse.swt.widgets
Class MenuItem
java.lang.Object
org.eclipse.swt.widgets.Widget
org.eclipse.swt.widgets.Item
org.eclipse.swt.widgets.MenuItem
-
All Implemented Interfaces:
-
Adaptable
- public class MenuItem
- extends
Item
Instances of this class represent a selectable user interface object
that issues notification when pressed and released.
-
Styles:
- CHECK, CASCADE, PUSH, RADIO, SEPARATOR
-
Events:
- Arm, Help, Selection
Note: Only one of the styles CHECK, CASCADE, PUSH, RADIO and SEPARATOR
may be specified.
IMPORTANT: This class is not intended to be subclassed.
Constructor Summary
|
MenuItem
(
Menu parent,
int style)
Constructs a new instance of this class given its parent
(which must be a Menu ) and a style value
describing its behavior and appearance. |
MenuItem
(
Menu parent,
int style,
int index)
Constructs a new instance of this class given its parent
(which must be a Menu ), a style value
describing its behavior and appearance, and the index
at which to place it in the items maintained by its parent. |
Method Summary
|
void
|
addSelectionListener
(
SelectionListener listener)
Adds the listener to the collection of listeners who will
be notified when the menu item is selected, by sending
it one of the messages defined in the SelectionListener
interface. |
boolean
|
getEnabled
()
Returns true if the receiver is enabled, and
false otherwise. |
Menu
|
getMenu
()
Returns the receiver's cascade menu if it has one or null
if it does not. |
Menu
|
getParent
()
Returns the receiver's parent, which must be a Menu . |
boolean
|
getSelection
()
Returns true if the receiver is selected,
and false otherwise. |
boolean
|
isEnabled
()
Returns true if the receiver is enabled and all
of the receiver's ancestors are enabled, and false
otherwise. |
void
|
removeSelectionListener
(
SelectionListener listener)
Removes the listener from the collection of listeners who will
be notified when the control is selected. |
void
|
setEnabled
(boolean enabled)
Enables the receiver if the argument is true ,
and disables it otherwise. |
void
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setImage
(
Image image)
Sets the image the receiver will display to the argument. |
void
|
setMenu
(
Menu menu)
Sets the receiver's pull down menu to the argument. |
void
|
setSelection
(boolean selection)
Sets the selection state of the receiver. |
Methods inherited from class org.eclipse.swt.widgets.
Widget
|
addDisposeListener,
addListener,
checkSubclass,
checkWidget,
dispose,
getAdapter,
getData,
getData,
getDisplay,
getStyle,
isDisposed,
notifyListeners,
removeDisposeListener,
removeListener,
setData,
setData,
toString
|
MenuItem
public MenuItem(
Menu parent,
int style)
- Constructs a new instance of this class given its parent
(which must be a
Menu ) and a style value
describing its behavior and appearance. The item is added
to the end of the items maintained by its parent.
The style value is either one of the style constants defined in
class SWT which is applicable to instances of this
class, or must be built by bitwise OR'ing together
(that is, using the int "|" operator) two or more
of those SWT style constants. The class description
lists the style constants that are applicable to the class.
Style bits are also inherited from superclasses.
-
Parameters:
-
parent - a menu control which will be the parent of the new instance (cannot be null) -
style - the style of control to construct
-
Throws:
-
IllegalArgumentException
-
- ERROR_NULL_ARGUMENT - if the parent is null
-
SWTException -
- ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent
- ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass
-
See Also:
-
SWT.CHECK ,
SWT.CASCADE ,
SWT.PUSH ,
SWT.RADIO ,
SWT.SEPARATOR ,
Widget.checkSubclass() ,
Widget.getStyle()
MenuItem
public MenuItem(
Menu parent,
int style,
int index)
- Constructs a new instance of this class given its parent
(which must be a
Menu ), a style value
describing its behavior and appearance, and the index
at which to place it in the items maintained by its parent.
The style value is either one of the style constants defined in
class SWT which is applicable to instances of this
class, or must be built by bitwise OR'ing together
(that is, using the int "|" operator) two or more
of those SWT style constants. The class description
lists the style constants that are applicable to the class.
Style bits are also inherited from superclasses.
-
Parameters:
-
parent - a menu control which will be the parent of the new instance (cannot be null) -
style - the style of control to construct -
index - the zero-relative index to store the receiver in its parent
-
Throws:
-
IllegalArgumentException
-
- ERROR_NULL_ARGUMENT - if the parent is null
- ERROR_INVALID_RANGE - if the index is not between 0 and the number of elements in the parent (inclusive)
-
SWTException -
- ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent
- ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass
-
See Also:
-
SWT.CHECK ,
SWT.CASCADE ,
SWT.PUSH ,
SWT.RADIO ,
SWT.SEPARATOR ,
Widget.checkSubclass() ,
Widget.getStyle()
getParent
public
Menu getParent()
- Returns the receiver's parent, which must be a
Menu .
-
-
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
setMenu
public void setMenu(
Menu menu)
- Sets the receiver's pull down menu to the argument.
Only
CASCADE menu items can have a
pull down menu. The sequence of key strokes, button presses
and/or button releases that are used to request a pull down
menu is platform specific.
Note: Disposing of a menu item that has a pull down menu
will dispose of the menu. To avoid this behavior, set the
menu to null before the menu item is disposed.
-
-
Parameters:
-
menu - the new pull down menu
-
Throws:
-
IllegalArgumentException
-
- ERROR_MENU_NOT_DROP_DOWN - if the menu is not a drop down menu
- ERROR_MENUITEM_NOT_CASCADE - if the menu item is not a
CASCADE
- ERROR_INVALID_ARGUMENT - if the menu has been disposed
- ERROR_INVALID_PARENT - if the menu is not in the same widget tree
-
SWTException -
- ERROR_WIDGET_DISPOSED - if the receiver has been disposed
- ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
getMenu
public
Menu getMenu()
- Returns the receiver's cascade menu if it has one or null
if it does not. Only
CASCADE menu items can have
a pull down menu. The sequence of key strokes, button presses
and/or button releases that are used to request a pull down
menu is platform specific.
-
-
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
setImage
public void setImage(
Image image)
- Sets the image the receiver will display to the argument.
Note: This operation is a hint and is not supported on
platforms that do not have this concept (for example, Windows NT).
-
-
Overrides:
-
setImage
in class
Item
-
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Parameters:
-
image - the image to display
-
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
setEnabled
public void setEnabled(boolean enabled)
- Enables the receiver if the argument is
true ,
and disables it otherwise. A disabled menu item is typically
not selectable from the user interface and draws with an
inactive or "grayed" look.
-
-
Parameters:
-
enabled - the new enabled 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
getEnabled
public boolean getEnabled()
- Returns
true if the receiver is enabled, and
false otherwise. A disabled menu item is typically
not selectable from the user interface and draws with an
inactive or "grayed" look.
-
-
Returns:
- the receiver's enabled state
-
Throws:
-
SWTException -
- ERROR_WIDGET_DISPOSED - if the receiver has been disposed
- ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
-
See Also:
-
isEnabled()
isEnabled
public boolean isEnabled()
- Returns
true if the receiver is enabled and all
of the receiver's ancestors are enabled, and false
otherwise. A disabled menu item is typically not selectable from the
user interface and draws with an inactive or "grayed" look.
-
-
Returns:
- the receiver's enabled state
-
Throws:
-
SWTException -
- ERROR_WIDGET_DISPOSED - if the receiver has been disposed
- ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
-
See Also:
-
getEnabled()
getSelection
public boolean getSelection()
- Returns
true if the receiver is selected,
and false otherwise.
When the receiver is of type CHECK or RADIO ,
it is selected when it is checked.
-
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Returns:
- the selection state
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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
setSelection
public void setSelection(boolean selection)
- Sets the selection state of the receiver.
When the receiver is of type CHECK or RADIO ,
it is selected when it is checked.
-
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Parameters:
-
selection - the new selection state
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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
addSelectionListener
public void addSelectionListener(
SelectionListener listener)
- Adds the listener to the collection of listeners who will
be notified when the menu item is selected, by sending
it one of the messages defined in the
SelectionListener
interface.
When widgetSelected is called, the stateMask field of the event object is valid.
widgetDefaultSelected is not called.
-
-
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:
-
SelectionListener ,
removeSelectionListener(org.eclipse.swt.events.SelectionListener) ,
SelectionEvent
removeSelectionListener
public void removeSelectionListener(
SelectionListener listener)
- Removes the listener from the collection of listeners who will
be notified when the control is selected.
-
-
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:
-
SelectionListener ,
addSelectionListener(org.eclipse.swt.events.SelectionListener)
Copyright (c) Innoopract Informationssysteme GmbH and others 2002, 2008. All rights reserved.
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