wpf属性更新后通知的问题

问题：两个checkbox更新后，绑定的属性并没有更新，请教各位大神带这么解决？只有200分，如果哪位能解决，全部奉上
代码如下：
view(XAML文件)：
<UserControl.Resources>
<ResourceDictionary>
<local:ShowConverter x:Key="sc"/>
</ResourceDictionary>
</UserControl.Resources>
<CheckBox Content="{Binding BSM.Commander_BTNMain.Name}" IsChecked="{Binding BSM.Commander_BTNMain.IsSelected}" >
<CheckBox Content="{Binding BSM.Commander_BTNSub.Name}" Grid.Column="1" IsChecked="{Binding BSM.Commander_BTNSub.IsSelected}" />
<Label>
<Label.Content>
<Label Grid.Column="1">
<Label.Content>
<MultiBinding Converter="{StaticResource sc}">
<Binding Path="BSM.Commander_BTNMain" Mode="OneWay"/>
<Binding Path="BSM.Commander_BTNSub"/>
</MultiBinding>
</Label.Content>
</Label>
Model:
public class ICheckItem : BindableBase
{
/// <summary>
///当前项是否选中
///</summary>
private bool isSelected;
public bool IsSelected
{
get { return isSelected; }
set
{
SetProperty(ref isSelected, value);
}
} /// <summary>
///名称
///</summary>
public string Name { get; set; }
}

public class BTNSysDeployModel : BindableBase
{ //主车
private ICheckItem commander_BTNMain = new ICheckItem();

public ICheckItem Commander_BTNMain
{
get { return commander_BTNMain; }
set
{
SetProperty(ref commander_BTNMain, value);
}
}
//副车
private ICheckItem commander_BTNSub = new ICheckItem();

public ICheckItem Commander_BTNSub
{
get { return commander_BTNSub; }
set
{
SetProperty(ref commander_BTNSub, value);
}
}
}
转换器：
public class ShowConverter : IMultiValueConverter
{
public object Convert(object[] values, Type targetType, object parameter, CultureInfo culture)
{
string show = "";
foreach (var item in values)
{
if (item is ICheckItem)
{
ICheckItem ic = (ICheckItem)item;
if (ic.IsSelected)
{
show += ic.Name + " ";
}
}
}

return show;
}

public object[] ConvertBack(object value, Type[] targetTypes, object parameter, CultureInfo culture)
{
throw new NotImplementedException();
}
}