public void keyPressed (KeyEvent ev)
	{	switch (ev.getKeyCode())
		{	case KeyEvent.VK_UP :
			case KeyEvent.VK_DOWN : 
				if (M==null)
				{	M=new PopupMenu();
					ListElement e=H.last();
					int i=0,n=Global.getParameter("history.length",10);
					while (e!=null && i<n)
					{	String t=(String)e.content();
						if (!t.equals(""))
						{	MenuItem item=new MenuItemAction(this,
								FileName.chop(t,MaxLength),t);
							M.add(item);
						}
						e=e.previous();
						i++;
					}
					add(M);
				}
				M.show(this,10,10);
				break;
			default : return;
		}
	}