List box with multiple data template - style for selected item

Question

I have List Box with 2 data template, i have a ItemContainerStyle for list box as well which will highlight the selected item in the list box.

Below is my code:

Answer 1

There are couple of issue with your 2nd DataTemplate.

In Below Code:

<DataTemplate x:Key="NewDataTemplate">
    <Border  
            Background="{Binding Converter={StaticResource BackgroundConvertor}}"
            Margin="0,2,0,0" 
            VerticalAlignment="Stretch"
            HorizontalAlignment="Stretch">
        <Grid> items ...</Grid>
   </Border>
</DataTemplate>

In above code look at :

Background="{Binding Converter={StaticResource BackgroundConvertor}}"

1. You are not providing any path. Thus your converter will not get any input value.
2. Also, you should specify the parameters in above binding.

Take a look at below example:

First in your ViewModel declare a property like below :

private MyObject myBackground;
public MyObject MyBackground
{
    get
    {
        return myBackground;
    }
    set
    {
        myBackground = value;
        NotifyPropertyChanged("MyBackground");
    }
}

Fill the values in MyBackground before changing the DataTemplate or in the Constructor of your ViewModel.

In your DataTemplate :

<DataTemplate x:Key="NewDataTemplate">
    <Border  
            Background="{Binding Path=MyBackground, Converter={StaticResource BackgroundConvertor} 
                                 ConverterParameter='1'}" />
            Margin="0,2,0,0" 
            VerticalAlignment="Stretch"
            HorizontalAlignment="Stretch">
        <Grid> items ...</Grid>
   </Border>
</DataTemplate>

The converter you specified in above code should be used here as well.

Note: The above example code is not tested. If there are any errors, then please try to solve it. And if you have any problems please feel free to ask.

Update:

You don't need to make any changes to your Answer Class.

In your ViewModel just declare a property like below:

private Answer myBackground;
public Answer MyBackground
{
    get
    {
        return myBackground;
    }
    set
    {
        myBackground = value;
        OnPropertyChanged("MyBackground");
    }
}

Use the XAML that I mentioned previously in my Answer.

Make changes to your converter like below code:

public class BackgroundConvertor: IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        SolidColorBrush solidColorBrush = null;

        if (value != null)
        {
            Answer answer = (Answer)value ;
            if (parameter != null)
            {
                if (answer.IsCorrect == 1 && parameter.ToString() == "0")
                {
                    solidColorBrush = new SolidColorBrush(Color.FromArgb((byte)255, (byte)201, (byte)235, (byte)242)); //blue color                                                       
                }
                else if (answer.IsCorrect == 1 && parameter.ToString() == "1")  
                {
                    solidColorBrush = new SolidColorBrush(Color.FromArgb((byte)255, (byte)201, (byte)242, (byte)169));//green color                                                        
                }
                else
                {
                    solidColorBrush = new SolidColorBrush(Color.FromArgb((byte)255, (byte)227, (byte)232, (byte)240));//Grey color.
                }
            }
            else if (answer.IsCorrect == 1)
            {
                solidColorBrush = new SolidColorBrush(Color.FromArgb((byte)255, (byte)201, (byte)242, (byte)169));//green color  
            }

            else
            {
                solidColorBrush = new SolidColorBrush(Color.FromArgb((byte)255, (byte)227, (byte)232, (byte)240));//Grey color.
            }
        }
        return solidColorBrush;
    }

    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
        return null;
    }
}