WPF MVVM：怎样的ViewModels互相沟通？ [英] WPF MVVM: How do ViewModels communicate with each other?

问题描述

我有一个观点上它具有两个子视图和一个ViewModel被分配到每个视图：

I have a View which has 2 sub views on it and a ViewModel is assigned to each view:

ViewA - ViewModelA
{ 
   ViewB - ViewModelB
   ViewC - ViewModelC
}

ViewB有一个文本框和ViewC有一个下拉框，这两者我需要ViewModelA访问。没有GUI控件本身，而是绑定值即文本框。文本和组合框的.SelectedItem。目前，我只是有ViewModelB和ViewModelC作为ViewModelA属性，但感觉错了。

ViewB has a text box and ViewC has a combobox, both of which i need access from ViewModelA. Not the GUI control itself, but the bound value i.e. .Text of the textbox and .SelectedItem of the ComboBox. Currently i just have ViewModelB and ViewModelC as properties on ViewModelA but it feels wrong.

什么是对视图模型相互没有打破MVVM模式通信的标准方式？我完全新的WPF / MVVM。

What's the standard way for view models to communicate with each other without breaking the MVVM pattern? I'm completely new to WPF/MVVM.

推荐答案

一个办法已经断开的ViewModels传达给对方是使用发布/订阅机制，如 PRISM 小号的 EventAggregator 。然而，在父/子视图模型的关系，我认为它的罚款父有过孩子视图模型直接了解和控制。

One way to have disconnected ViewModels communicate to each other is to use a publish / subscribe mechanism such as PRISMs EventAggregator. However, in a parent / child ViewModel relationship, I think it's fine for the parent to have direct knowledge and control over the child ViewModel.

就个人而言，我不认为构成一个ViewModel出其他的ViewModels是一个不好的做法。我做这一切的时候。 我一般偏向于在我的ViewModels继承组成。

Personally, I don't think composing a ViewModel out of other ViewModels is a bad practice. I do it all the time. I generally favor composition over inheritance in my ViewModels.

这篇关于WPF MVVM：怎样的ViewModels互相沟通？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！