android - 如何获取在 ContextMenu 上单击的 Item 的位置？

Question

我正在使用此代码获取上下文菜单上的已单击项目位置:

public boolean onContextItemSelected(MenuItem item) {
    AdapterContextMenuInfo info = (AdapterContextMenuInfo) item.getMenuInfo();
    int index = info.position;
}

这里建议:

Android: How to find the position clicked from the context menu

但我在以下行收到 NullPointerException:

 int index = info.position;

为什么会这样？

编辑

我有 2 个这样的 contextMenu 注册 View :

button1.onClick(view v){
registerForContextMenu(v);
openContextMenu(v);
}

button2.onClick(view v){
registerForContextMenu(v);
openContextMenu(v);
}

然后根据 v.getId() 填充菜单。

Answer 1

可以直接使用:

编辑开始

@Override
public void onCreateContextMenu(ContextMenu menu, View v, ContextMenuInfo menuInfo) {
    AdapterView.AdapterContextMenuInfo info;
    try {
        info = (AdapterView.AdapterContextMenuInfo) menuInfo;
    } catch (ClassCastException e) {
        // If the menu object can't be cast, logs an error.
        Log.e("MENU", "bad menuInfo", e);
        return;
    }
    position = sectionAdapter.getIndexForPosition(info.position);
    menu.setHeaderTitle("");
    String[] menuItems = { "item1","item2","item3","item4" };
    for (int i = 0; i < menuItems.length; i++) {
        menu.add(Menu.NONE, i, i, menuItems[i]);
    }
}

编辑结束

public boolean onContextItemSelected(MenuItem item) {
    // TODO Auto-generated method stub
    int position = item.getItemId();
    switch (position) 
    {

        case 0:
        break;
        .
        .
        .
        default:
        break;
    }
}

希望对你有所帮助。