DataContextProxy silverlight 组合框 - 有更好的方法吗？
我正在使用 Dan Wahlin 解决了在发现这一发现之前的许多小时内看起来非常困难的问题。
我有一个绑定到 ObservableCollection 的组合框。该组合框还具有以下值：DisplayMemberPath=AccountNumber 和 SelectedValue={Binding SelectedAccount}。然后，我有一个 DataForm，其 CurrentItem 属性也绑定到 SelectedAccount。在我的 DataForm 中，我有一些需要额外下拉列表的字段（AcctCode、UsageCode 等）。为了缓解在 DataForm 内部遇到的绑定问题，我实现了 datacontextproxy，允许我将 cbobox 的 ItemsSource 设置为 {Binding Source={StaticResource DataContextProxy}, Path=DataSource.AccountCodes}".
在偶然发现这个问题之前，我真的很挣扎，因为我没有使用域上下文，所以我不能使用 Kyle Mcllelens ComboBoxex，也不能使用绝大多数。我确实尝试在我的视图中创建 ViewModel 的实例作为本地资源，但是 a) 我觉得 MVVM 很脏，b) 它无法创建新的 VM 实例，因为我的 VM 需要一个 谢谢
在任何情况下，我只是想知道是否应该有一种方法可以实现更高的性能、更多的 MVVM、更可维护、更好的等等。
，
斯科特
I'm using the datacontextproxy class defined by Dan Wahlin to solve what seemed so very difficult for the many many hours leading up to that discovery.
I have a combobox that is bound to an ObservableCollection<Accounts>. The combobox also has the values: DisplayMemberPath=AccountNumber, and the SelectedValue={Binding SelectedAccount}. I then have a DataForm that has its CurrentItem property also bound to SelectedAccount. Inside my DataForm, I have a handful of fields that require additional dropdowns (AcctCode, UsageCode, etc). To mitigate the binding issues I ran into inside of a DataForm, I implemented the datacontextproxy, allowing me to set the ItemsSource of my cbobox to {Binding Source={StaticResource DataContextProxy}, Path=DataSource.AccountCodes}". This is working great in terms of the end result.
Before stumbling onto this, I really struggled with this find. I'm not using a domaincontext, so I couldn't use Kyle Mcllelans ComboBoxex, nor could I use the vast majority of solutions offered. I did try to create an instance of my ViewModel as a local resource in my View, but a) I felt dirty in terms of MVVM, and b) It failed to create a new VM instance, as my VM requires a number of service references to be passed in on construct.
In any case, I'm simply wondering if there's a way I should be doing this that's either more performant, more MVVM, more maintainable, more bestest'er, etc etc.
Thanks,
Scott
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Scott 我也决定使用 DataContextProxy。我认为使用它仍然提供了一个很好的 MVVM 解决方案，其中视图仅通过绑定或命令了解 VM。
我认为在 Silverlight 5 发布之前将其用作临时解决方案。 Silverlight 5 中引入了祖先绑定，这将为数据绑定提供更大的灵活性。
Scott I also have settled on using the DataContextProxy. I think use of it still provides a good MVVM solution where the view only has knowledge of the VM via binding or commanding.
I see use of it as a temporary solution until Silverlight 5 ships. In Silverlight 5 ancestor binding is introduced which will provide more flexibility in data binding.