/*******************************************************************************
* Copyright (c) 2002, 2015 Innoopract Informationssysteme GmbH and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* Innoopract Informationssysteme GmbH - initial API and implementation
* EclipseSource - ongoing development
******************************************************************************/
package org.eclipse.swt.widgets;
import org.eclipse.rap.rwt.internal.lifecycle.WidgetLCA;
import org.eclipse.swt.SWT;
import org.eclipse.swt.SWTException;
import org.eclipse.swt.events.ArmListener;
import org.eclipse.swt.events.DisposeEvent;
import org.eclipse.swt.events.DisposeListener;
import org.eclipse.swt.events.HelpListener;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.events.SelectionListener;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.internal.widgets.IItemHolderAdapter;
import org.eclipse.swt.internal.widgets.menuitemkit.MenuItemLCA;
/**
* Instances of this class represent a selectable user interface object
* that issues notification when pressed and released.
* <dl>
* <dt><b>Styles:</b></dt>
* <dd>CHECK, CASCADE, PUSH, RADIO, SEPARATOR</dd>
* <dt><b>Events:</b></dt>
* <dd>Arm, Help, Selection</dd>
* </dl>
* <p>
* Note: Only one of the styles CHECK, CASCADE, PUSH, RADIO and SEPARATOR
* may be specified.
* </p><p>
* IMPORTANT: This class is <em>not</em> intended to be subclassed.
* </p>
*/
public class MenuItem extends Item {
private final Menu parent;
private Menu menu;
private DisposeListener menuDisposeListener;
private boolean selection;
private int userId;
private AcceleratorBinding acceleratorBinding;
/**
* Constructs a new instance of this class given its parent
* (which must be a <code>Menu</code>) and a style value
* describing its behavior and appearance. The item is added
* to the end of the items maintained by its parent.
* <p>
* The style value is either one of the style constants defined in
* class <code>SWT</code> which is applicable to instances of this
* class, or must be built by <em>bitwise OR</em>'ing together
* (that is, using the <code>int</code> "|" operator) two or more
* of those <code>SWT</code> style constants. The class description
* lists the style constants that are applicable to the class.
* Style bits are also inherited from superclasses.
* </p>
*
* @param parent a menu control which will be the parent of the new instance (cannot be null)
* @param style the style of control to construct
*
* @exception IllegalArgumentException <ul>
* <li>ERROR_NULL_ARGUMENT - if the parent is null</li>
* </ul>
* @exception SWTException <ul>
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent</li>
* <li>ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass</li>
* </ul>
*
* @see SWT#CHECK
* @see SWT#CASCADE
* @see SWT#PUSH
* @see SWT#RADIO
* @see SWT#SEPARATOR
* @see Widget#checkSubclass
* @see Widget#getStyle
*/
public MenuItem( Menu parent, int style ) {
super( parent, checkStyle( style ) );
this.parent = parent;
parent.getAdapter( IItemHolderAdapter.class ).add( this );
}
/**
* Constructs a new instance of this class given its parent
* (which must be a <code>Menu</code>), a style value
* describing its behavior and appearance, and the index
* at which to place it in the items maintained by its parent.
* <p>
* The style value is either one of the style constants defined in
* class <code>SWT</code> which is applicable to instances of this
* class, or must be built by <em>bitwise OR</em>'ing together
* (that is, using the <code>int</code> "|" operator) two or more
* of those <code>SWT</code> style constants. The class description
* lists the style constants that are applicable to the class.
* Style bits are also inherited from superclasses.
* </p>
*
* @param parent a menu control which will be the parent of the new instance (cannot be null)
* @param style the style of control to construct
* @param index the zero-relative index to store the receiver in its parent
*
* @exception IllegalArgumentException <ul>
* <li>ERROR_NULL_ARGUMENT - if the parent is null</li>
* <li>ERROR_INVALID_RANGE - if the index is not between 0 and the number of elements in the parent (inclusive)</li>
* </ul>
* @exception SWTException <ul>
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent</li>
* <li>ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass</li>
* </ul>
*
* @see SWT#CHECK
* @see SWT#CASCADE
* @see SWT#PUSH
* @see SWT#RADIO
* @see SWT#SEPARATOR
* @see Widget#checkSubclass
* @see Widget#getStyle
*/
public MenuItem( Menu parent, int style, int index ) {
super( parent, checkStyle( style ) );
this.parent = parent;
parent.getAdapter( IItemHolderAdapter.class ).insert( this, index );
}
/**
* Returns the receiver's parent, which must be a <code>Menu</code>.
*
* @return the receiver's parent
*
* @exception SWTException <ul>
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
* </ul>
*/
public Menu getParent() {
checkWidget();
return parent;
}
/**
* Sets the receiver's pull down menu to the argument.
* Only <code>CASCADE</code> 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.
* <p>
* 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.
* </p>
*
* @param menu the new pull down menu
*
* @exception IllegalArgumentException <ul>
* <li>ERROR_MENU_NOT_DROP_DOWN - if the menu is not a drop down menu</li>
* <li>ERROR_MENUITEM_NOT_CASCADE - if the menu item is not a <code>CASCADE</code></li>
* <li>ERROR_INVALID_ARGUMENT - if the menu has been disposed</li>
* <li>ERROR_INVALID_PARENT - if the menu is not in the same widget tree</li>
* </ul>
* @exception SWTException <ul>
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
* </ul>
*/
public void setMenu( Menu menu ) {
checkWidget();
if( this.menu != menu ) {
if( ( style & SWT.CASCADE ) == 0 ) {
SWT.error( SWT.ERROR_MENUITEM_NOT_CASCADE );
}
if( menu != null ) {
if( menu.isDisposed() ) {
SWT.error( SWT.ERROR_INVALID_ARGUMENT );
}
if( ( menu.getStyle() & SWT.DROP_DOWN ) == 0 ) {
SWT.error( SWT.ERROR_MENU_NOT_DROP_DOWN );
}
if( menu.getParent() != getParent().getParent() ) {
SWT.error( SWT.ERROR_INVALID_PARENT );
}
}
removeMenuDisposeListener();
/* Assign the new menu */
if( this.menu != null ) {
this.menu.cascade = null;
}
this.menu = menu;
if( menu != null ) {
menu.cascade = this;
}
addMenuDisposeListener();
}
}
/**
* Returns the receiver's cascade menu if it has one or null
* if it does not. Only <code>CASCADE</code> 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.
*
* @return the receiver's menu
*
* @exception SWTException <ul>
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
* </ul>
*/
public Menu getMenu() {
checkWidget();
return menu;
}
/**
* Sets the identifier associated with the receiver to the argument.
*
* @param id the new identifier. This must be a non-negative value. System-defined identifiers are negative values.
*
* @exception SWTException <ul>
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
* <li>ERROR_INVALID_ARGUMENT - if called with an negative-valued argument.</li>
* </ul>
*
* @since 1.4
*/
public void setID( int id ) {
checkWidget();
if( id < 0 ) {
error( SWT.ERROR_INVALID_ARGUMENT );
}
userId = id;
}
/**
* Gets the identifier associated with the receiver.
*
* @exception SWTException <ul>
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
* </ul>
*
* @since 1.4
*/
public int getID() {
checkWidget();
return userId;
}
/**
* Sets the image the receiver will display to the argument.
* <p>
* Note: This operation is a hint and is not supported on
* platforms that do not have this concept (for example, Windows NT).
* </p>
*
* @param image the image to display
*
* @exception SWTException <ul>
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
* </ul>
*/
@Override
public void setImage( Image image ) {
checkWidget();
if( ( style & SWT.SEPARATOR ) == 0 ) {
super.setImage( image );
}
}
/**
* Sets the widget accelerator. An accelerator is the bit-wise
* OR of zero or more modifier masks and a key. Examples:
* <code>SWT.MOD1 | SWT.MOD2 | 'T', SWT.MOD3 | SWT.F2</code>.
* <code>SWT.CONTROL | SWT.SHIFT | 'T', SWT.ALT | SWT.F2</code>.
* The default value is zero, indicating that the menu item does
* not have an accelerator.
*
* @param accelerator an integer that is the bit-wise OR of masks and a key
*
* </ul>
* @exception SWTException <ul>
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
* </ul>
*
* @since 2.1
*/
public void setAccelerator( int accelerator ) {
checkWidget();
if( accelerator != 0 ) {
if( acceleratorBinding == null ) {
acceleratorBinding = new AcceleratorBinding( this );
}
acceleratorBinding.setAccelerator( accelerator );
} else if( acceleratorBinding != null ) {
acceleratorBinding.release();
acceleratorBinding = null;
}
}
/**
* Returns the widget accelerator. An accelerator is the bit-wise
* OR of zero or more modifier masks and a key. Examples:
* <code>SWT.CONTROL | SWT.SHIFT | 'T', SWT.ALT | SWT.F2</code>.
* The default value is zero, indicating that the menu item does
* not have an accelerator.
*
* @return the accelerator or 0
*
* </ul>
* @exception SWTException <ul>
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
* </ul>
*
* @since 2.1
*/
public int getAccelerator() {
checkWidget();
return acceleratorBinding != null ? acceleratorBinding.getAccelerator() : 0;
}
//////////
// Enabled
/**
* Enables the receiver if the argument is <code>true</code>,
* and disables it otherwise. A disabled menu item is typically
* not selectable from the user interface and draws with an
* inactive or "grayed" look.
*
* @param enabled the new enabled state
*
* @exception SWTException <ul>
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
* </ul>
*/
public void setEnabled( boolean enabled ) {
checkWidget();
removeState( DISABLED );
if( !enabled ) {
addState( DISABLED );
}
}
/**
* Returns <code>true</code> if the receiver is enabled, and
* <code>false</code> otherwise. A disabled menu item is typically
* not selectable from the user interface and draws with an
* inactive or "grayed" look.
*
* @return the receiver's enabled state
*
* @exception SWTException <ul>
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
* </ul>
*
* @see #isEnabled
*/
public boolean getEnabled() {
checkWidget();
return !hasState( DISABLED );
}
/**
* Returns <code>true</code> if the receiver is enabled and all
* of the receiver's ancestors are enabled, and <code>false</code>
* otherwise. A disabled menu item is typically not selectable from the
* user interface and draws with an inactive or "grayed" look.
*
* @return the receiver's enabled state
*
* @exception SWTException <ul>
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
* </ul>
*
* @see #getEnabled
*/
public boolean isEnabled() {
return getEnabled() && parent.isEnabled();
}
////////////
// Selection
/**
* Returns <code>true</code> if the receiver is selected,
* and false otherwise.
* <p>
* When the receiver is of type <code>CHECK</code> or <code>RADIO</code>,
* it is selected when it is checked.
*
* @return the selection state
*
* @exception SWTException <ul>
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
* </ul>
*/
public boolean getSelection() {
checkWidget();
return selection;
}
/**
* Sets the selection state of the receiver.
* <p>
* When the receiver is of type <code>CHECK</code> or <code>RADIO</code>,
* it is selected when it is checked.
*
* @param selection the new selection state
*
* @exception SWTException <ul>
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
* </ul>
*/
public void setSelection( boolean selection ) {
checkWidget();
if( ( style & ( SWT.CHECK | SWT.RADIO ) ) != 0 ) {
this.selection = selection;
}
}
///////////////////////
// Listener maintenance
/**
* 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 <code>SelectionListener</code>
* interface.
* <p>
* When <code>widgetSelected</code> is called, the stateMask field of the event object is valid.
* <code>widgetDefaultSelected</code> is not called.
* </p>
*
* @param listener the listener which should be notified
*
* @exception IllegalArgumentException <ul>
* <li>ERROR_NULL_ARGUMENT - if the listener is null</li>
* </ul>
* @exception SWTException <ul>
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
* </ul>
*
* @see SelectionListener
* @see #removeSelectionListener
* @see SelectionEvent
*/
public void addSelectionListener( SelectionListener listener ) {
checkWidget();
if( listener == null ) {
SWT.error( SWT.ERROR_NULL_ARGUMENT );
}
TypedListener typedListener = new TypedListener( listener );
addListener( SWT.Selection, typedListener );
addListener( SWT.DefaultSelection, typedListener );
}
/**
* Removes the listener from the collection of listeners who will
* be notified when the control is selected.
*
* @param listener the listener which should no longer be notified
*
* @exception IllegalArgumentException <ul>
* <li>ERROR_NULL_ARGUMENT - if the listener is null</li>
* </ul>
* @exception SWTException <ul>
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
* </ul>
*
* @see SelectionListener
* @see #addSelectionListener
*/
public void removeSelectionListener( SelectionListener listener ) {
checkWidget();
if( listener == null ) {
SWT.error( SWT.ERROR_NULL_ARGUMENT );
}
removeListener( SWT.Selection, listener );
removeListener( SWT.DefaultSelection, listener );
}
/**
* Adds the listener to the collection of listeners who will
* be notified when the help events are generated for the control, by sending
* it one of the messages defined in the <code>HelpListener</code>
* interface.
*
* @param listener the listener which should be notified
*
* @exception IllegalArgumentException <ul>
* <li>ERROR_NULL_ARGUMENT - if the listener is null</li>
* </ul>
* @exception SWTException <ul>
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
* </ul>
*
* @see HelpListener
* @see #removeHelpListener
* @since 1.3
*/
public void addHelpListener( HelpListener listener ) {
checkWidget();
if( listener == null ) {
error( SWT.ERROR_NULL_ARGUMENT );
}
TypedListener typedListener = new TypedListener( listener );
addListener( SWT.Help, typedListener );
}
/**
* Removes the listener from the collection of listeners who will
* be notified when the help events are generated for the control.
*
* @param listener the listener which should no longer be notified
*
* @exception IllegalArgumentException <ul>
* <li>ERROR_NULL_ARGUMENT - if the listener is null</li>
* </ul>
* @exception SWTException <ul>
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
* </ul>
*
* @see HelpListener
* @see #addHelpListener
* @since 1.3
*/
public void removeHelpListener( HelpListener listener ) {
checkWidget();
if( listener == null ) {
error( SWT.ERROR_NULL_ARGUMENT );
}
removeListener( SWT.Help, listener );
}
/**
* Adds the listener to the collection of listeners who will
* be notified when the arm events are generated for the control, by sending
* it one of the messages defined in the <code>ArmListener</code>
* interface.
*
* @param listener the listener which should be notified
*
* @exception IllegalArgumentException <ul>
* <li>ERROR_NULL_ARGUMENT - if the listener is null</li>
* </ul>
* @exception SWTException <ul>
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
* </ul>
*
* @see ArmListener
* @see #removeArmListener
* @since 1.3
*/
public void addArmListener( ArmListener listener ) {
checkWidget();
if( listener == null ) {
error( SWT.ERROR_NULL_ARGUMENT );
}
TypedListener typedListener = new TypedListener( listener );
addListener( SWT.Arm, typedListener );
}
/**
* Removes the listener from the collection of listeners who will
* be notified when the arm events are generated for the control.
*
* @param listener the listener which should no longer be notified
*
* @exception IllegalArgumentException <ul>
* <li>ERROR_NULL_ARGUMENT - if the listener is null</li>
* </ul>
* @exception SWTException <ul>
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
* </ul>
*
* @see ArmListener
* @see #addArmListener
* @since 1.3
*/
public void removeArmListener( ArmListener listener ) {
checkWidget();
removeListener( SWT.Arm, listener );
}
@Override
@SuppressWarnings( "unchecked" )
public <T> T getAdapter( Class<T> adapter ) {
if( adapter == WidgetLCA.class ) {
return ( T )MenuItemLCA.INSTANCE;
}
return super.getAdapter( adapter );
}
//////////////////
// Item overrides
@Override
void releaseWidget() {
super.releaseWidget();
if( acceleratorBinding != null ) {
acceleratorBinding.release();
acceleratorBinding = null;
}
}
@Override
final void releaseChildren() {
if( menu != null ) {
removeMenuDisposeListener();
menu.dispose();
menu = null;
}
}
@Override
final void releaseParent() {
super.releaseParent();
parent.getAdapter( IItemHolderAdapter.class ).remove( this );
}
@Override
String getNameText() {
String result;
if( ( style & SWT.SEPARATOR ) != 0 ) {
result = "|";
} else {
result = super.getNameText();
}
return result;
}
///////////////////////////////////////////////////////
// Helping methods to observe the disposal of the menu
private void addMenuDisposeListener() {
if( menu != null ) {
if( menuDisposeListener == null ) {
menuDisposeListener = new DisposeListener() {
@Override
public void widgetDisposed( DisposeEvent event ) {
menu = null;
}
};
}
menu.addDisposeListener( menuDisposeListener );
}
}
private void removeMenuDisposeListener() {
if( menu != null ) {
menu.removeDisposeListener( menuDisposeListener );
}
}
void handleAcceleratorActivation() {
if( ( style & SWT.CHECK ) != 0 ) {
selection = !selection;
} else if ( ( style & SWT.RADIO ) != 0 ) {
deselectOtherRadios();
selection = true;
}
notifyListeners( SWT.Selection, new Event() );
}
private void deselectOtherRadios() {
for( MenuItem item : parent.getItems() ) {
if( item != this && ( item.getStyle() & SWT.RADIO ) != 0 && item.getSelection() ) {
item.setSelection( false );
item.notifyListeners( SWT.Selection, new Event() );
}
}
}
///////////////////////////////////////
// Helping methods to verify arguments
private static int checkStyle( int style ) {
return checkBits( style,
SWT.PUSH,
SWT.CHECK,
SWT.RADIO,
SWT.SEPARATOR,
SWT.CASCADE,
0 );
}
///////////////////
// Skinning support
@Override
void reskinChildren( int flags ) {
if( menu != null ) {
menu.reskin( flags );
}
super.reskinChildren( flags );
}
}