MVVM Combobox绑定 [英] MVVM Combobox binding

问题描述

我有一个组合框似乎没有更新它的视图模型。

在视图上我有

 < ComboBox Grid.Row =0
 Grid.Column =1
 ToolTip =官员的当前排名
 ItemsSource ={Binding Path = RanksAvailable}
 DisplayMemberPath =Name 
 SelectedValuePath =Name
 SelectedValue ={Binding Path = SelectedRank，Mode = TwoWay}/> 
  
 
 
 
在视图模型中我有
  public List< Rank> RanksAvailable {get; set;} 
 private Rank _selectedRank; 
 
 public Rank SelectedRank 
 {
 get {return _selectedRank; } 
 set 
 {
 if（_selectedRank！= value）
 {
 _selectedRank = value; 
 this.isDirty = true; 
 RaisePropertyChanged（SelectedRank）; 
} 
} 
} 
  
正在填充组合框，我只是不能似乎得到一个值出来。 
解决方案
问题是你使用SelectedValuePath =Name只是删除它，它会工作。 
 $ b 
您的ComboBox将会成为 -  
 < ComboBox Grid.Row =0
 Grid.Column =1
 ToolTip =官员的当前排名
 ItemsSource ={Binding Path = RanksAvailable}
 DisplayMemberPath =Name
 SelectedValue ={Binding Path = SelectedRank，Mode = TwoWay}/> 
  
 
I have a combobox that doesn't seem to be updated it's view model. 

On the view I have 
<ComboBox Grid.Row="0" 
           Grid.Column="1" 
           ToolTip="Current rank of the officer" 
           ItemsSource="{Binding Path=RanksAvailable}"
           DisplayMemberPath="Name"
           SelectedValuePath="Name"
           SelectedValue="{Binding Path=SelectedRank, Mode=TwoWay}"/>
in the view model I have
    public List<Rank> RanksAvailable {get; set;}
    private Rank _selectedRank;

    public Rank SelectedRank 
    {
        get { return _selectedRank; }
        set
        {
            if (_selectedRank != value)
            {
                _selectedRank = value;
                this.isDirty = true;
                RaisePropertyChanged("SelectedRank");
            }
        }
    }
the combobox is being populated alright, I just can't seem to get a value out of it. 
解决方案
The problem is you are using SelectedValuePath="Name" just remove it and it will work.

Your ComboBox will become-
<ComboBox Grid.Row="0" 
           Grid.Column="1" 
           ToolTip="Current rank of the officer" 
           ItemsSource="{Binding Path=RanksAvailable}"
           DisplayMemberPath="Name"
           SelectedValue="{Binding Path=SelectedRank, Mode=TwoWay}"/>


                        
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