Listbox item trigger colour change - wpf

Question

I am trying to change the colour of the items in a listbox based on a trigger using MVVM
<Border Grid.Row="1" Width="300" Margin="0,0,20,0" BorderThickness="1,2,1,1" CornerRadius="5" BorderBrush="#FF999393" Background="#FFE9EDF1" >
<ListBox ItemsSource="{Binding LogMessageList, UpdateSourceTrigger=PropertyChanged}" Background="{x:Null}" Margin="3" BorderBrush="{x:Null}" FontSize="13.333" >
<ListBox.ItemContainerStyle>
<Style TargetType="ListBoxItem">
<Setter Property="Foreground" Value="#FF403E3E" />
<Style.Triggers>
<DataTrigger Binding="{Binding FatalError, UpdateSourceTrigger=PropertyChanged}" Value="Fatal">
<Setter Property="Foreground" Value="Firebrick" />
</DataTrigger>
</Style.Triggers>
</Style>
</ListBox.ItemContainerStyle>
</ListBox>
I'm setting the property change correctly but nothing seems to change.
Thanks
EDIT:
Still stuck. Trying
<ListBox.ItemContainerStyle>
<Style TargetType="ListBoxItem">
<Setter Property="Foreground" Value="#FF403E3E" />
<Style.Triggers>
<DataTrigger Binding="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type Window}},Path=DataContext.FatalError, UpdateSourceTrigger=PropertyChanged}" Value="Fatal">
<Setter Property="Foreground" Value="Firebrick" />
</DataTrigger>
</Style.Triggers>
</Style>
</ListBox.ItemContainerStyle>

Answer 1

Tried your scenario. Please refer the below code example:
View Model
public class Vm : INotifyPropertyChanged
{
public ObservableCollection<VmUser> VmUsers { get; set; }
private string errorType;
public string ErrorType
{
get { return errorType; }
set
{
errorType = value;
Raise("ErrorType");
}
}
public event PropertyChangedEventHandler PropertyChanged;
public void Raise(string propertyName)
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
}
public class VmUser
{
public string Name { get; set; }
public int Age { get; set; }
}
Set the DataContext of window in constructor :
public MainWindow()
{
Vm = new Vm
{
VmUsers = new ObservableCollection<VmUser>
{
new VmUser { Name = "Gil", Age = 1 },
new VmUser { Name = "Dan", Age = 2 },
new VmUser { Name = "John", Age = 3 },
},
ErrorType = "Fatal"
};
InitializeComponent();
DataContext = TheVm;
}
Defined ListBox in XAML as:
<ListBox Grid.Row="2" ItemsSource="{Binding VmUsers}" DisplayMemberPath="Name" SelectedValuePath="Age">
<ListBox.ItemContainerStyle>
<Style TargetType="ListBoxItem">
<Setter Property="Foreground" Value="#FF403E3E" />
<Style.Triggers>
<DataTrigger Binding="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type Window}},Path=DataContext.ErrorType, UpdateSourceTrigger=PropertyChanged}" Value="Fatal">
<Setter Property="Foreground" Value="Red" />
</DataTrigger>
</Style.Triggers>
</Style>
</ListBox.ItemContainerStyle>
</ListBox>
To test the scenario I have wrote a small test to toggle the ErrorType on click on button
private void Button_Click(object sender, RoutedEventArgs e)
{
var vm = this.DataContext as Vm;
if (vm != null)
{
if (vm.ErrorType == "Fatal")
{
vm.ErrorType = "Non Fatal";
}
else
{
vm.ErrorType = "Fatal";
}
}
}
With above example foreground color changes based on ErrorType.