import org.eclipse.swt.events.DragDetectListener; //导入依赖的package包/类
/**
 * Swaps two tabs and corresponding notes when a user drags one to another.
 */
private void addSwapTabListener() {
	tabFolder.addDragDetectListener(new DragDetectListener() {
		@Override
		public void dragDetected(DragDetectEvent dragDetectedEvent) {
			final Rectangle viewRectangle = Geometry.toDisplay(tabFolder.getParent(), tabFolder.getBounds());
			final Tracker tracker = new Tracker(tabFolder, SWT.NONE);
			tracker.setStippled(true);
			tracker.addListener(SWT.Move, new Listener() {
				@Override
				public void handleEvent(Event event) {
					Point location = new Point(event.x - viewRectangle.x, event.y - viewRectangle.y);
					CTabItem tabAtLocation = tabFolder.getItem(location);
					if (tabAtLocation != null) {
						// Move tracker to follow mouse cursor.
						tracker.setRectangles(new Rectangle[] { tabAtLocation.getBounds() });
					} else {
						// Mouse cursor no longer above any tab in the action bar, hide tacker.
						tracker.setRectangles(new Rectangle[0]);
					}
				}
			});
			if (tracker.open()) {
				Rectangle[] rectangles = tracker.getRectangles();
				if (rectangles.length > 0) {
					CTabItem tabToSwap = tabFolder.getItem(new Point(rectangles[0].x, rectangles[0].y));
					// Swap selected tab with the one situated at the mouse cursor's position.
					if (tabToSwap != null) {
						swapNoteTabs(tabFolder.indexOf(tabToSwap));
					}
				}
			}
			tracker.close();
			tracker.dispose();
		}
	});
}
 

import org.eclipse.swt.events.DragDetectListener; //导入依赖的package包/类
/**
 * Hook an SWT listener on the canvas where the chart is drawn.
 * The purpose of this method is to allow some degree of customization.
 *
 * @param listener The SWT listener to attach to the canvas.
 */
public void addSWTListener(EventListener listener) {
    if (listener instanceof ControlListener) {
        this.canvas.addControlListener((ControlListener) listener);
    }
    else if (listener instanceof DisposeListener) {
        this.canvas.addDisposeListener((DisposeListener) listener);
    }
    else if (listener instanceof DragDetectListener) {
        this.canvas.addDragDetectListener((DragDetectListener) listener);
    }
    else if (listener instanceof FocusListener) {
        this.canvas.addFocusListener((FocusListener) listener);
    }
    else if (listener instanceof HelpListener) {
        this.canvas.addHelpListener((HelpListener) listener);
    }
    else if (listener instanceof KeyListener) {
        this.canvas.addKeyListener((KeyListener) listener);
    }
    else if (listener instanceof MenuDetectListener) {
        this.canvas.addMenuDetectListener((MenuDetectListener) listener);
    }
    else if (listener instanceof MouseListener) {
        this.canvas.addMouseListener((MouseListener) listener);
    }
    else if (listener instanceof MouseMoveListener) {
        this.canvas.addMouseMoveListener((MouseMoveListener) listener);
    }
    else if (listener instanceof MouseTrackListener) {
        this.canvas.addMouseTrackListener((MouseTrackListener) listener);
    }
    else if (listener instanceof MouseWheelListener) {
        this.canvas.addMouseWheelListener((MouseWheelListener) listener);
    }
    else if (listener instanceof PaintListener) {
        this.canvas.addPaintListener((PaintListener) listener);
    }
    else if (listener instanceof TraverseListener) {
        this.canvas.addTraverseListener((TraverseListener) listener);
    }
}
 

import org.eclipse.swt.events.DragDetectListener; //导入依赖的package包/类
public void addDragDetectListener(DragDetectListener listener){
	this.text.addDragDetectListener(listener);
}
 

import org.eclipse.swt.events.DragDetectListener; //导入依赖的package包/类
public void removeDragDetectListener(DragDetectListener listener){
	this.text.removeDragDetectListener(listener);
}
 

import org.eclipse.swt.events.DragDetectListener; //导入依赖的package包/类
/**
 * Adds the listener to the collection of listeners who will be notified
 * when a drag gesture occurs, by sending it one of the messages defined in
 * the <code>DragDetectListener</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 DragDetectListener
 * @see #removeDragDetectListener
 * 
 * @since 3.3
 */
public void addDragDetectListener(DragDetectListener listener) {
	checkWidget();
	if (listener == null)
		error(SWT.ERROR_NULL_ARGUMENT);
	TypedListener typedListener = new TypedListener(listener);
	addListener(SWT.DragDetect, typedListener);
}
 

import org.eclipse.swt.events.DragDetectListener; //导入依赖的package包/类
/**
 * Removes the listener from the collection of listeners who will be
 * notified when a drag gesture occurs.
 * 
 * @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 DragDetectListener
 * @see #addDragDetectListener
 * 
 * @since 3.3
 */
public void removeDragDetectListener(DragDetectListener listener) {
	checkWidget();
	if (listener == null)
		error(SWT.ERROR_NULL_ARGUMENT);
	if (eventTable == null)
		return;
	eventTable.unhook(SWT.DragDetect, listener);
}
 

import org.eclipse.swt.events.DragDetectListener; //导入依赖的package包/类
public void addDragDetectListener(DragDetectListener listener) {
	
	tree.addDragDetectListener(listener);
}
 

import org.eclipse.swt.events.DragDetectListener; //导入依赖的package包/类
public void removeDragDetectListener(DragDetectListener listener) {
	
	tree.removeDragDetectListener(listener);
}