WPF ItemsControl 的 ItemsSource 绑定的一个bug
不知道是Bug还是什么, 碰到这个问题的.
我测试了一下,所有ItemsControls子类都有这个问题. 譬如: ComboBox
public class NameValue
{
public object Value { get; set; }
public string Name { get; set; }
}
public class TestObj: INotifyPropertyChanged
{
public event PropertyChangedEventHandler PropertyChanged;
protected void Notify(string propName)
{
if (this.PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(propName));
}
}
int _v1;
public int V1{
get{ return _v1;}
set{
if (this._v1== value) { return; }
this._v1= value;
Notify("V1");
}
}
int _v2;
public int V2{
get{ return _v2;}
set{
if (this._v2== value) { return; }
this._v2= value;
Notify("V2");
}
}
}
初始化List
List<NameValue> lst = new List<NameValue>();
lst.Add(new NameValue(){Name=”item1”, Value=”1”});
lst.Add(new NameValue(){Name=”item2”, Value=”2”});
lst.Add(new NameValue(){Name=”item3”, Value=”3”});
绑定到ComboBox
cbo1.ItemsSource = lst;
cbo2.ItemsSource = lst;
dataGrid.DataContext = new TestObj(){
V1 = 1,
V2 = 2
};
xaml代码
<Grid x:Name="dataGrid">
<ComboBox x:Name="cbo1" DisplayMemberPath="Name" SelectedValuePath="Value" Width="80" IsSynchronizedWithCurrentItem="True" SelectedValue="{Binding Path=V1}"/>
<ComboBox x:Name="cbo2" DisplayMemberPath="Name" SelectedValuePath="Value" Width="80" IsSynchronizedWithCurrentItem="True" SelectedValue="{Binding Path=V2}"/>
</Grid>
测试看看, 结果竟然是cbo1和cbo2联动了
解决办法
cbo1.ItemsSource = lst.ToArray();
cbo2.ItemsSource = lst.ToArray();
dataGrid.DataContext = new TestObj(){
V1 = 1,
V2 = 2
};
ItemsSource 指向了同一个List导致select同步了, 通过ToArray()方法,其实clone了2个NameValue数组实例, 这样就不会产生select同步的.
