为什么registerForContextMenu传递onCreateContextMenu空ContextMenuInfo？ [英] Why is registerForContextMenu passing onCreateContextMenu a null ContextMenuInfo?

问题描述

在的onCreate，我附上一个线性布局视图给一个变量活动视图。然后，我打电话 registerForContextMenu（活动视图）。看来，一切工作正常，上下文菜单被创建，该项目是可以点击的，但是，在 onContextItemSelected ，我称之为 AdapterContextMenuInfo信息=（AdapterContextMenuInfo） item.getMenuInfo（），我得到一个NullPointerException异常。我跟踪的空menuInfo变量的所有回来的路上找到 registerForContextMeu（活动视图）从一开始就通过OnCreateContextMenu空ContextMenuInfo。这究竟是为什么？我做同样的过程，不同的看法，一个ListView，旁边的的LinearLayout，这个问题不存在那里。

In onCreate, I attach a linear layout view to a variable activeView. I then call registerForContextMenu(activeView). It appears that everything works properly, the context menu gets created, the items are clickable, however, in onContextItemSelected, I call AdapterContextMenuInfo info = (AdapterContextMenuInfo) item.getMenuInfo() and I get a nullpointerexception. I've traced the null menuInfo variable all the way back to find that registerForContextMeu(activeView) is passing OnCreateContextMenu a null ContextMenuInfo from the start. Why is this happening? I do the same process for a different view, a listView, alongside the linearlayout, and the problem doesn't exist there.

推荐答案

什么是你希望摆脱getMenuInfo的（）？在任何情况下，我不认为它会通过的LinearLayout填充去做，相信顶多你就可以得到这催生菜单中的视图（相同的LinearLayout）。

What are you expecting to get out of getMenuInfo()? In any case, I don't think it will be populated by a LinearLayout, I believe at most you'll be able to get the View (the same LinearLayout) which spawned the menu.

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