Display Image in WPF Listview

Question

I want to show an image in my listview but i don't know how i should do this. My Guest class has the method GetGuestImage() it returns me a absolute path. When this file exists is should be loaded and when not a placeholder-image should be loaded.

How can i realize this?

<ListView x:Name="listview">
                    <ListView.View>
                        <GridView>
                            <GridViewColumn DisplayMemberBinding="{Binding GetGuestImage()}" Header="Image" />
                            <GridViewColumn DisplayMemberBinding="{Binding Vorname}" Header="Vorname" />
                            <GridViewColumn DisplayMemberBinding="{Binding Nachname}" Header="Nachname" />
                            <GridViewColumn DisplayMemberBinding="{Binding Postleitzahl}" Header="PLZ" />
                            <GridViewColumn DisplayMemberBinding="{Binding Ort}" Header="Ort" />
                            <GridViewColumn DisplayMemberBinding="{Binding Land}" Header="Land" />
                        </GridView>
                    </ListView.View>
                </ListView>

Answer 1

Use a Converter for that.

public class NullGuestImageToPlaceholderConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        if (value == null || !File.Exists(value as string))
            return placeholderImage;

        return GetImage(value);
    }

    public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        throw new NotImplementedException();
    }
}

XAML:

<ListView x:Name="listview">
    <ListView.View>
        <GridView>
            <GridViewColumn DisplayMemberBinding="{Binding GuestImage, Converter={StaticResource nullGuestImageConverter}}" Header="Image" />
            <!-- your other columns -->
        </GridView>
    </ListView.View>
</ListView>

I don't have the GetGuestImage implementation or your full XAML, so that's the most I can do for now.

nullGuestImageConverter should be the x:Key of the converter, defined in your XAML's resources (like <UserControl.Resources>), and placeholderImage should be the implementation of how you retrieve said placeholder image (which I guess appears in GetGuestImage()).

In fact, I guess you could simply replace the content of the Convert method by your GetGuestImage one, but I can't know for sure.