menuitem.java

源码为Eclipse开源开发平台桌面开发工具SWT的源代码,

 *
 * @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;
}

/**
 * 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 ();
	if ((style & (SWT.CHECK | SWT.RADIO)) == 0) return false;
	if ((OS.IsPPC || OS.IsSP) && parent.hwndCB != 0) return false;
	int hMenu = parent.handle;
	MENUITEMINFO info = new MENUITEMINFO ();
	info.cbSize = MENUITEMINFO.sizeof;
	info.fMask = OS.MIIM_STATE;
	boolean success = OS.GetMenuItemInfo (hMenu, id, false, info);
	if (!success) error (SWT.ERROR_CANNOT_GET_SELECTION);
	return (info.fState & OS.MFS_CHECKED) !=0;
}

/**
 * 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 control 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 ();
}

void releaseChild () {
	super.releaseChild ();
	if (menu != null) menu.dispose ();
	menu = null;
	parent.destroyItem (this);
}

void releaseMenu () {
	if (!OS.IsSP) setMenu (null);
	menu = null;
}

void releaseWidget () {
	if (menu != null) menu.releaseResources ();
	menu = null;
	super.releaseWidget ();
	if (accelerator != 0) {
		parent.destroyAccelerators ();
	}
	accelerator = 0;
	display.removeMenuItem (this);
	parent = null;
}

/**
 * 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 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
 */
public void removeArmListener (ArmListener listener) {
	checkWidget ();
	if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
	if (eventTable == null) return;
	eventTable.unhook (SWT.Arm, listener);
}
/**
 * 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 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
 */
public void removeHelpListener (HelpListener listener) {
	checkWidget ();
	if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
	if (eventTable == null) return;
	eventTable.unhook (SWT.Help, listener);
}
/**
 * Removes the listener from the collection of listeners who will
 * be notified when the control is selected.
 *
 * @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 #addSelectionListener
 */
public void removeSelectionListener (SelectionListener listener) {
	checkWidget ();
	if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
	if (eventTable == null) return;
	eventTable.unhook (SWT.Selection, listener);
	eventTable.unhook (SWT.DefaultSelection,listener);	
}

void selectRadio () {
	int index = 0;
	MenuItem [] items = parent.getItems ();
	while (index < items.length && items [index] != this) index++;
	int i = index - 1;
	while (i >= 0 && items [i].setRadioSelection (false)) --i;
	int j = index + 1;
	while (j < items.length && items [j].setRadioSelection (false)) j++;
	setSelection (true);
}

/**
 * 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>.
 *
 * @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>
 */
public void setAccelerator (int accelerator) {
	checkWidget ();
	if (this.accelerator == accelerator) return;
	this.accelerator = accelerator;
	parent.destroyAccelerators ();
}

/**
 * Enables the receiver if the argument is <code>true</code>,
 * and disables it otherwise. A disabled control 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 ();
	if ((OS.IsPPC || OS.IsSP) && parent.hwndCB != 0) {
		int hwndCB = parent.hwndCB;
		TBBUTTONINFO info = new TBBUTTONINFO ();
		info.cbSize = TBBUTTONINFO.sizeof;
		info.dwMask = OS.TBIF_STATE;
		OS.SendMessage (hwndCB, OS.TB_GETBUTTONINFO, id, info);
		info.fsState &= ~OS.TBSTATE_ENABLED;
		if (enabled) info.fsState |= OS.TBSTATE_ENABLED;
		OS.SendMessage (hwndCB, OS.TB_SETBUTTONINFO, id, info);		
	} else {
		int hMenu = parent.handle;
		if (OS.IsWinCE) {
			int index = parent.indexOf (this);
			if (index == -1) return;
			int uEnable = OS.MF_BYPOSITION | (enabled ? OS.MF_ENABLED : OS.MF_GRAYED);
			OS.EnableMenuItem (hMenu, index, uEnable);
		} else {
			MENUITEMINFO info = new MENUITEMINFO ();
			info.cbSize = MENUITEMINFO.sizeof;
			info.fMask = OS.MIIM_STATE;
			boolean success = OS.GetMenuItemInfo (hMenu, id, false, info);
			if (!success) error (SWT.ERROR_CANNOT_SET_ENABLED);
			int bits = OS.MFS_DISABLED | OS.MFS_GRAYED;
			if (enabled) {
				if ((info.fState & bits) == 0) return;
				info.fState &= ~bits;
			} else {
				if ((info.fState & bits) == bits) return;
				info.fState |= bits;
			}
			success = OS.SetMenuItemInfo (hMenu, id, false, info);
			if (!success) error (SWT.ERROR_CANNOT_SET_ENABLED);
		}
	}
	parent.destroyAccelerators ();
	parent.redraw ();
}

/**
 * Sets the image the receiver will display to the argument.
 * <p>
 * Note: This feature is not available on all window systems (for example, Window NT),
 * in which case, calling this method will silently do nothing.
 *
 * @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>
 */
public void setImage (Image image) {
	checkWidget ();
	if ((style & SWT.SEPARATOR) != 0) return;
	super.setImage (image);
	if (OS.IsWinCE) {
		if ((OS.IsPPC || OS.IsSP) && parent.hwndCB != 0) {
			int hwndCB = parent.hwndCB;
			TBBUTTONINFO info = new TBBUTTONINFO ();
			info.cbSize = TBBUTTONINFO.sizeof;
			info.dwMask = OS.TBIF_IMAGE;
			info.iImage = parent.imageIndex (image);
			OS.SendMessage (hwndCB, OS.TB_SETBUTTONINFO, id, info);
		}
		return;
	}
	if ((OS.WIN32_MAJOR << 16 | OS.WIN32_MINOR) < (4 << 16 | 10)) {
		return;
	}
	MENUITEMINFO info = new MENUITEMINFO ();
	info.cbSize = MENUITEMINFO.sizeof;
	info.fMask = OS.MIIM_BITMAP;
	if (image != null) info.hbmpItem = OS.HBMMENU_CALLBACK;
	int hMenu = parent.handle;
	OS.SetMenuItemInfo (hMenu, id, false, info);
	parent.redraw ();
}

/**
 * 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.
 *
 * @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 ();

	/* Check to make sure the new menu is valid */
	if ((style & SWT.CASCADE) == 0) {
		error (SWT.ERROR_MENUITEM_NOT_CASCADE);
	}
	if (menu != null) {
		if (menu.isDisposed()) error(SWT.ERROR_INVALID_ARGUMENT);
		if ((menu.style & SWT.DROP_DOWN) == 0) {
			error (SWT.ERROR_MENU_NOT_DROP_DOWN);
		}
		if (menu.parent != parent.parent) {
			error (SWT.ERROR_INVALID_PARENT);
		}
	}

	/* Assign the new menu */
	Menu oldMenu = this.menu;
	if (oldMenu == menu) return;
	if (oldMenu != null) oldMenu.cascade = null;
	this.menu = menu;

	/* Assign the new menu in the OS */		
	if ((OS.IsPPC || OS.IsSP) && parent.hwndCB != 0) {
		if (OS.IsPPC) {
			int hwndCB = parent.hwndCB;
			int hMenu = menu == null ? 0 : menu.handle;
			OS.SendMessage (hwndCB, OS.SHCMBM_SETSUBMENU, id, hMenu);
		}
		if (OS.IsSP) error (SWT.ERROR_CANNOT_SET_MENU);
	} else {
		/*
		* Feature in Windows.  When SetMenuItemInfo () is used to
		* set a submenu and the menu item already has a submenu,
		* Windows destroys the previous menu.  This is undocumented
		* and unexpected but not necessarily wrong.  The fix is to
		* remove the item with RemoveMenu () which does not destroy
		* the submenu and then insert the item with InsertMenuItem ().
		*/
		int hMenu = parent.handle;
		MENUITEMINFO info = new MENUITEMINFO ();
		info.cbSize = MENUITEMINFO.sizeof;
		info.fMask = OS.MIIM_DATA;
		int index = 0;
		while (OS.GetMenuItemInfo (hMenu, index, true, info)) {
			if (info.dwItemData == id) break;
			index++;
		}
		if (info.dwItemData != id) return;
		boolean hasBitmap = false, success = false;
		
		/*