替换ListView的ItemsSource而不丢失SelectedItem

隐马尔可夫模型。。。怎么样:

<ListView Name="listView" SelectionChanged="listView_SelectionChanged" DataContextChanged="listView_DataContextChanged" />

在SelectionChanged处理程序中,将SelectedItem保存在ListView的标记中

private void listView_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
    (sender as ListView).Tag = (sender as ListView).SelectedItem;
}

ListView的DataContext更改后,根据新集合计算保存在标记中的最后一个SelectedItem,并从该集合中设置新项:

    private void listView_DataContextChanged(object sender, DependencyPropertyChangedEventArgs e)
    {
        List<CustomClass> newList = e.NewValue as List<CustomClass>;
        if (newList != null && (sender as ListView).Tag != null)
        {
            foreach (CustomClass cClass in newList)
                if (cClass.Equals((sender as ListView).Tag as CustomClass))
                    (sender as ListView).SelectedItem = cClass;
        }
    }

最后,我编写了映射程序代码,加载了一个observeCollection,其中的代理对象指向从服务层检索到的真实对象。每次从服务层获取更新时,映射程序代码都会根据需要添加/删除/更新代理对象。