Wpf DataTemplate

Question

I have Defined a DataTemplate for ListView to Display the fileInfo details. This is the DataTemplate

<DataTemplate x:Key="srchFileListTemplate">
    <StackPanel>
        <WrapPanel>
            <TextBlock FontWeight="Bold" FontFamily="Century Gothic"
                Text="FileName :"/>
            <TextBlock Margin="10,0,0,0" FontWeight="Bold"
                FontFamily="Century Gothic" Text="{Binding Path=Name}"/>
        </WrapPanel>
        <WrapPanel>
            <TextBlock FontFamily="Century Gothic" Text="FilePath :"/>
            <TextBlock Margin="20,0,0,0" FontFamily="Century Gothic"
                Text="{Binding Path = DirectoryName}"/>
        </WrapPanel>
        <WrapPanel>
            <TextBlock FontFamily="Century Gothic" Text="File Size :"/>
            <TextBlock Margin="20,0,0,0" FontFamily="Century Gothic"
                Text="{Binding Path = Length}"/>
            <TextBlock Text="Bytes"/>
        </WrapPanel>
        <WrapPanel>
            <TextBlock FontFamily="Century Gothic" Text="File Extension:"/>
            <TextBlock Margin="20,0,0,0" FontFamily="Century Gothic"
                Text="{Binding Path = Extension}"/>
        </WrapPanel>
    </StackPanel>
</DataTemplate> 

ImagesSource for the ListView is List<FileInfo>

I have to add a customized icon according to the Extension of the file to the List. Is it possible to pass the extension to a method to get the icon path in the existing DataTemplate?

Answer 1

You need a converter:

[ValueConversion(typeof(string), typeof(ImageSource))]
public class FileIconConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        string fileName = value as string;
        if (fileName == null)
            return null;
        return IconFromFile(fileName);
    }

    private ImageSource IconFromFile(string fileName)
    {
        // logic to get the icon based on the filename
    }

    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
        // The opposite conversion doesn't make sense...
        throw new NotImplementedException();
    }

}

You then need to declare an instance of the converter in the resources:

<Window.Resources>
    <local:FileIconConverter x:Key="iconConverter" />
</Window.Resources>

And you use it in your binding as follows:

<Image Source="{Binding FullName, Converter={StaticResource iconConverter}}" />