大家好，老师来了，老师又来了……幸好不收稿费也不收学费。所以一个ContextMenu就可以写n篇，大家也没有什么意见，这次老师要说的是……控制MenuItem的属性。应用场景如下：针对目标，右键菜单可能启用一些菜单项，禁用一些菜单项。简单的例子是，选中图片文件可以用Acdsee打开，选中word文件就是用word打开了。这里的解决思路是从YUI 邮件组搜到的。所以邮件组是个好东西。但是还需要挖掘啊。上面Todd是这么说的。（前文没看，可能Todd刚和文中麦扣打笔战）
On Jan 30 , 2007 , at 11 : 54 AM , Todd Kloots wrote:Michael -If you set the " lazyload " configuration property to " true " for your ContextMenu , then its contents willnot get created and the menu itself will not berendered until the " contextmenu " event is actuallyfired.That said , if you're creating a ~ 1000 elements withunique context menus , then , yes it would be better toreuse a single ContextMenu instance and reuse it. Youcan subscribe to your context menu's " showEvent " anduse the " contextEventTarget " to determine what childnode was the actual target of the " contextmenu " eventthat triggered the display of the menu. You can thenuse that target element to determine what content youneed to add or remove from the menu.Make sense?- Todd
上下文不重要，重点是这里说明了一个事情，menu是有showEvent这个事件的，往前追溯就是他老爸（的老爸） YAHOO.widget.Module有那么一个东西。继承给Menu-ContextMenu了。所以基于这个showEvent事件触发时，兄弟们去取menu.contextEventTarget。就能拿到目标的那个DOM对象了。拿到这个对象后，就可以根据对象的数据（属性）来决定要不要显示一些菜单。代码如下。照旧片断.
先注册
oContextMenu.showEvent.subscribe(onContextMenuShow, this );然后读取数据就行了。外面的鞭炮声和爆炸案有得一拼
function onContextMenuShow() ... { disabledMenu(oContextMenu.contextEventTarget); } function disabledMenu(vo) ... { //alert(oTarget.first); if(vo.last||vo.dataType=='m')...{ oContextMenu.getItem(4).cfg.setProperty("disabled", true); //alert(oContextMenu.getItem(3)); }else...{ oContextMenu.getItem(4).cfg.setProperty("disabled", false); } if(vo.first||vo.dataType=='m')...{ oContextMenu.getItem(3).cfg.setProperty("disabled", true); }else...{ oContextMenu.getItem(3).cfg.setProperty("disabled", false); } }问题就是这样解决的。
