双向数据绑定问题与组合框 - WPF [英] Two way data Binding issue with combo box - WPF

问题描述

我有一个包含 Combobox 的视图。 Combobox SelectedItem 属性是绑定到 SelectedX 属性视图模型为双向数据绑定。当viewModel初始化时， SelectedX 属性设置正确。但是之后，当视图呈现时，它重置 SelectedX 的值（因为绑定是双向的）。
因此， Combobox 的双向数据绑定基本上不工作。请指教。

这是我的观点的xaml。我首先使用关系和SelectedX的适当值初始化View模型。当视图呈现时，组合框将重置SelectedX的值。 （我想通过添加断点）。希望这有助于

 < ComboBox Grid.Row =1Grid.Column =1Margin =5 =WhiteBorderBrush =DarkGray
 SelectedItem ={Binding SelectedX，Mode = TwoWay}
 ItemsSource ={Binding Relationships}DisplayMemberPath =Value
 SelectedValuePath = SelectedValue ={Binding Key，Mode = TwoWay}
 IsEditable =FalseIsReadOnly =True/> 
  
 
 
解决方案
 
  SelectedValue = {Binding Key，Mode = TwoWay}
  
这将更改 SelectedItem 到 SelectedValue 。
 
I have a View that contains a Combobox. The Combobox SelectedItem property is data bound to SelectedX property of View Model as two way data binding. When the viewModel is initialized, the SelectedX property is set correctly. But after that when the view renders, it resets the value of SelectedX(since the binding is two-way).
So the two way data binding for the Combobox is basically not working. Please advise.

This is the xaml for my view. I initialize the View model first with apprpriate values for Relationships and SelectedX. When the view renders, the combo box resets the value for SelectedX. (I figured that by adding breakpoints). Hope this helps
   <ComboBox Grid.Row="1" Grid.Column="1" Margin="5" Background="White"     BorderBrush="DarkGray"
              SelectedItem="{Binding SelectedX, Mode=TwoWay}" 
              ItemsSource="{Binding Relationships}" DisplayMemberPath="Value" 
              SelectedValuePath="Value" SelectedValue="{Binding Key, Mode=TwoWay}"
              IsEditable="False" IsReadOnly="True" />

解决方案
SelectedValue="{Binding Key, Mode=TwoWay}"
This will change the SelectedItem to its SelectedValue.

                        
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