if ( editor != null )
if ( editor != null && editor.getEditorSite( )!=null)
	private void bingdingKey( int newPageIndex )	{		final IKeyBindingService service = getSite( ).getKeyBindingService( );		final IEditorPart editor = (IEditorPart) pages.get( newPageIndex );		if ( editor != null )		{			editor.setFocus( );			// There is no selected page, so deactivate the active service.			if ( service instanceof INestableKeyBindingService )			{				final INestableKeyBindingService nestableService = (INestableKeyBindingService) service;				if ( editor != null )				{					nestableService.activateKeyBindingService( editor.getEditorSite( ) );				}				else				{					nestableService.activateKeyBindingService( null );				}			}			else			{			}		}	}