ccombo.java

源码为Eclipse开源开发平台桌面开发工具SWT的源代码,

* @exception SWTError(ERROR_CANNOT_GET_COUNT)
*	when the operation fails
*/
public int getItemCount () {
	checkWidget();
	return list.getItemCount ();
}
/**
* Gets the height of one item.
* <p>
* This operation will fail if the height of
* one item could not be queried from the OS.
*
* @return the height of one item in the widget
*
* @exception SWTError(ERROR_THREAD_INVALID_ACCESS)
*	when called from the wrong thread
* @exception SWTError(ERROR_WIDGET_DISPOSED)
*	when the widget has been disposed
* @exception SWTError(ERROR_CANNOT_GET_ITEM_HEIGHT)
*	when the operation fails
*/
public int getItemHeight () {
	checkWidget();
	return list.getItemHeight ();
}
/**
* Gets the items.
* <p>
* This operation will fail if the items cannot
* be queried from the OS.
*
* @return the items in the widget
*
* @exception SWTError(ERROR_THREAD_INVALID_ACCESS)
*	when called from the wrong thread
* @exception SWTError(ERROR_WIDGET_DISPOSED)
*	when the widget has been disposed
* @exception SWTError(ERROR_CANNOT_GET_ITEM)
*	when the operation fails
*/
public String [] getItems () {
	checkWidget();
	return list.getItems ();
}
char getMnemonic (String string) {
	int index = 0;
	int length = string.length ();
	do {
		while ((index < length) && (string.charAt (index) != '&')) index++;
		if (++index >= length) return '\0';
		if (string.charAt (index) != '&') return string.charAt (index);
		index++;
	} while (index < length);
 	return '\0';
}
/**
* Gets the selection.
* <p>
* @return a point representing the selection start and end
*
* @exception SWTError(ERROR_THREAD_INVALID_ACCESS)
*	when called from the wrong thread
* @exception SWTError(ERROR_WIDGET_DISPOSED)
*	when the widget has been disposed
*/
public Point getSelection () {
	checkWidget();
	return text.getSelection ();
}
/**
* Gets the index of the selected item.
* <p>
* Indexing is zero based.
* If no item is selected -1 is returned.
*
* @return the index of the selected item.
*
* @exception SWTError(ERROR_THREAD_INVALID_ACCESS)
*	when called from the wrong thread
* @exception SWTError(ERROR_WIDGET_DISPOSED)
*	when the widget has been disposed
*/
public int getSelectionIndex () {
	checkWidget();
	return list.getSelectionIndex ();
}
public int getStyle () {
	int style = super.getStyle();
	style &= ~SWT.READ_ONLY;
	if (!text.getEditable()) style |= SWT.READ_ONLY; 
	return style;
}
/**
* Gets the widget text.
* <p>
* If the widget has no text, an empty string is returned.
*
* @return the widget text
*
* @exception SWTError(ERROR_THREAD_INVALID_ACCESS)
*	when called from the wrong thread
* @exception SWTError(ERROR_WIDGET_DISPOSED)
*	when the widget has been disposed
*/
public String getText () {
	checkWidget();
	return text.getText ();
}
/**
* Gets the height of the combo's text field.
* <p>
* The operation will fail if the height cannot 
* be queried from the OS.

* @return the height of the combo's text field.
* 
* @exception SWTError(ERROR_THREAD_INVALID_ACCESS)
*	when called from the wrong thread
* @exception SWTError(ERROR_WIDGET_DISPOSED)
*	when the widget has been disposed
* @exception SWTError(ERROR_ERROR_CANNOT_GET_ITEM_HEIGHT)
*	when the operation fails
*/
public int getTextHeight () {
	checkWidget();
	return text.getLineHeight();
}
/**
* Gets the text limit.
* <p>
* @return the text limit
* 
* @exception SWTError(ERROR_THREAD_INVALID_ACCESS)
*	when called from the wrong thread
* @exception SWTError(ERROR_WIDGET_DISPOSED)
*	when the widget has been disposed
*/
public int getTextLimit () {
	checkWidget();
	return text.getTextLimit ();
}
/**
 * Gets the number of items that are visible in the drop
 * down portion of the receiver's list.
 *
 * @return the number of items that are visible
 *
 * @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 3.0
 */
public int getVisibleItemCount () {
	checkWidget ();
	return visibleItemCount;
}
void handleFocus (int type) {
	if (isDisposed()) return;
	switch (type) {
		case SWT.FocusIn: {
			if (hasFocus) return;
			if (getEditable ()) text.selectAll ();
			hasFocus = true;
			Shell shell = getShell ();
			shell.removeListener(SWT.Deactivate, listener);
			shell.addListener(SWT.Deactivate, listener);
			Display display = getDisplay();
			display.removeFilter(SWT.FocusIn, filter);
			display.addFilter(SWT.FocusIn, filter);
			Event e = new Event();
			notifyListeners(SWT.FocusIn, e);
			break;
		}
		case SWT.FocusOut: {
			if (!hasFocus) return;
			Control focusControl = getDisplay().getFocusControl();
			if (focusControl == arrow || focusControl == list || focusControl == text) return;
			hasFocus = false;
			Shell shell = getShell ();
			shell.removeListener(SWT.Deactivate, listener);
			Display display = getDisplay();
			display.removeFilter(SWT.FocusIn, filter);
			Event e = new Event();
			notifyListeners(SWT.FocusOut, e);
			break;
		}
	}
}
/**
* Gets the index of an item.
* <p>
* The list is searched starting at 0 until an
* item is found that is equal to the search item.
* If no item is found, -1 is returned.  Indexing
* is zero based.
*
* @param string the search item
* @return the index of the item
*
* @exception SWTError(ERROR_THREAD_INVALID_ACCESS)
*	when called from the wrong thread
* @exception SWTError(ERROR_WIDGET_DISPOSED)
*	when the widget has been disposed
* @exception SWTError(ERROR_NULL_ARGUMENT)
*	when string is null
*/
public int indexOf (String string) {
	checkWidget();
	if (string == null) SWT.error (SWT.ERROR_NULL_ARGUMENT);
	return list.indexOf (string);
}
/**
* Gets the index of an item.
* <p>
* The widget is searched starting at start including
* the end position until an item is found that
* is equal to the search itenm.  If no item is
* found, -1 is returned.  Indexing is zero based.
*
* @param string the search item
* @param start the starting position
* @return the index of the item
*
* @exception SWTError(ERROR_THREAD_INVALID_ACCESS)
*	when called from the wrong thread
* @exception SWTError(ERROR_WIDGET_DISPOSED)
*	when the widget has been disposed
* @exception SWTError(ERROR_NULL_ARGUMENT)
*	when string is null
*/
public int indexOf (String string, int start) {
	checkWidget();
	if (string == null) SWT.error (SWT.ERROR_NULL_ARGUMENT);
	return list.indexOf (string, start);
}

void initAccessible() {
	AccessibleAdapter accessibleAdapter = new AccessibleAdapter() {
		public void getName(AccessibleEvent e) {
			String name = null;
			Label label = getAssociatedLabel ();
			if (label != null) {
				name = stripMnemonic(label.getText());
			}
			e.result = name;
		}
		public void getKeyboardShortcut(AccessibleEvent e) {
			String shortcut = null;
			Label label = getAssociatedLabel ();
			if (label != null) {
				String text = label.getText();
				if (text != null) {
					char mnemonic = getMnemonic(text);
					if (mnemonic != '\0') {
						shortcut = "Alt+"+mnemonic; //$NON-NLS-1$
					}
				}
			}
			e.result = shortcut;
		}
		public void getHelp(AccessibleEvent e) {
			e.result = getToolTipText();
		}
	};
	getAccessible().addAccessibleListener(accessibleAdapter);
	text.getAccessible().addAccessibleListener(accessibleAdapter);
	list.getAccessible().addAccessibleListener(accessibleAdapter);
	
	getAccessible().addAccessibleTextListener(new AccessibleTextAdapter() {
		public void getCaretOffset(AccessibleTextEvent e) {
			e.offset = text.getCaretPosition();
		}
	});
	
	getAccessible().addAccessibleControlListener(new AccessibleControlAdapter() {
		public void getChildAtPoint(AccessibleControlEvent e) {
			Point testPoint = toControl(new Point(e.x, e.y));
			if (getBounds().contains(testPoint)) {
				e.childID = ACC.CHILDID_SELF;
			}
		}
		
		public void getLocation(AccessibleControlEvent e) {
			Rectangle location = getBounds();
			Point pt = toDisplay(new Point(location.x, location.y));
			e.x = pt.x;
			e.y = pt.y;
			e.width = location.width;
			e.height = location.height;
		}
		
		public void getChildCount(AccessibleControlEvent e) {
			e.detail = 0;
		}
		
		public void getRole(AccessibleControlEvent e) {
			e.detail = ACC.ROLE_COMBOBOX;
		}
		
		public void getState(AccessibleControlEvent e) {
			e.detail = ACC.STATE_NORMAL;
		}

		public void getValue(AccessibleControlEvent e) {
			e.result = getText();
		}
	});
}
boolean isDropped () {
	return popup.getVisible ();
}
public boolean isFocusControl () {
	checkWidget();
	if (text.isFocusControl() || arrow.isFocusControl() || list.isFocusControl() || popup.isFocusControl()) {
		return true;
	} 
	return super.isFocusControl();
}
void internalLayout () {
	if (isDropped ()) dropDown (false);
	
	Rectangle rect = getClientArea();
	int width = rect.width;
	int height = rect.height;
	Point arrowSize = arrow.computeSize(SWT.DEFAULT, height);
	text.setBounds (0, 0, width - arrowSize.x, height);
	arrow.setBounds (width - arrowSize.x, 0, arrowSize.x, arrowSize.y);
}
void listEvent (Event event) {
	switch (event.type) {
		case SWT.Dispose:
			if (getShell() != popup.getParent()) {
				String[] items = list.getItems();
				int selectionIndex = list.getSelectionIndex();
				popup = null;
				list = null;
				createPopup(items, selectionIndex);
			}
			break;
		case SWT.FocusIn: {
			handleFocus (SWT.FocusIn);
			break;
		}
		case SWT.MouseUp: {
			if (event.button != 1) return;
			dropDown (false);
			break;
		}
		case SWT.Selection: {
			int index = list.getSelectionIndex ();
			if (index == -1) return;
			text.setText (list.getItem (index));
			text.selectAll ();
			list.setSelection(index);
			Event e = new Event();
			e.time = event.time;
			e.stateMask = event.stateMask;
			e.doit = event.doit;
			notifyListeners(SWT.Selection, e);
			event.doit = e.doit;
			break;
		}
		case SWT.Traverse: {
			switch (event.detail) {
				case SWT.TRAVERSE_RETURN:
				case SWT.TRAVERSE_ESCAPE:
				case SWT.TRAVERSE_ARROW_PREVIOUS:
				case SWT.TRAVERSE_ARROW_NEXT:
					event.doit = false;
					break;
			}
			Event e = new Event();
			e.time = event.time;
			e.detail = event.detail;
			e.doit = event.doit;
			e.character = event.character;
			e.keyCode = event.keyCode;
			notifyListeners(SWT.Traverse, e);
			event.doit = e.doit;
			event.detail = e.detail;
			break;
		}
		case SWT.KeyUp: {		
			Event e = new Event();
			e.time = event.time;
			e.character = event.character;
			e.keyCode = event.keyCode;
			e.stateMask = event.stateMask;
			notifyListeners(SWT.KeyUp, e);
			break;
		}
		case SWT.KeyDown: {
			if (event.character == SWT.ESC) { 
				// Escape key cancels popup list
				dropDown (false);
			}
			if ((event.stateMask & SWT.ALT) != 0 && (event.keyCode == SWT.ARROW_UP || event.keyCode == SWT.ARROW_DOWN)) {
				dropDown (false);
			}
			if (event.character == SWT.CR) {
				// Enter causes default selection
				dropDown (false);
				Event e = new Event();
				e.time = event.time;
				e.stateMask = event.stateMask;
				notifyListeners(SWT.DefaultSelection, e);
			}
			// At this point the widget may have been disposed.
			// If so, do not continue.
			if (isDisposed()) break;
			Event e = new Event();
			e.time = event.time;
			e.character = event.character;
			e.keyCode = event.keyCode;
			e.stateMask = event.stateMask;
			notifyListeners(SWT.KeyDown, e);
			break;
			
		}
	}
}
void popupEvent(Event event) {
	switch (event.type) {
		case SWT.Paint:
			// draw black rectangle around list
			Rectangle listRect = list.getBounds();
			Color black = getDisplay().getSystemColor(SWT.COLOR_BLACK);
			event.gc.setForeground(black);
			event.gc.drawRectangle(0, 0, listRect.width + 1, listRect.height + 1);
			break;
		case SWT.Close:
			event.doit = false;
			dropDown (false);
			break;
		case SWT.Deactivate:
			dropDown (false);
			break;
	}
}
public void redraw () {
	super.redraw();
	text.redraw();
	arrow.redraw();
	if (popup.isVisible()) list.redraw();
}
public void redraw (int x, int y, int width, int height, boolean all) {
	super.redraw(x, y, width, height, true);
}

/**
* Removes an item at an index.
* <p>
* Indexing is zero based.