值转换器未称为XAML

Question

I have put breakpoints inside the Value Converter and they are never triggered, but the page renders with no image being shown.

The XAML:

xmlns:datatypes="clr-namespace:DataTypes_Portable;assembly=DataTypes_WinPhone8"
...
<phone:PhoneApplicationPage.Resources>
    <datatypes:WinPhone8ImageConverter x:Key="ImageConverter" />
</phone:PhoneApplicationPage.Resources>
...
<Image x:Name="LevelImage" HorizontalAlignment="Left" Height="Auto" VerticalAlignment="Top" Width="Auto" Margin="0" Grid.ColumnSpan="5" Source="{Binding Converter={StaticResource ImageConverter}, Path=App.Main.Game.CurrentLevel.CurrentPart.Image}"/>

The CS:

public class WinPhone8ImageConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        var imageProvider = value as WinPhone8ImageProvider;
        return imageProvider.Image;
    }

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

From what I can understand (by process of trial and elimination and looking at what exceptions are thrown) the problem is coming with part of the XAML where I am trying to bind to the value.

At a breakpoint the value at App.Main.Game.CurrentLevel.CurrentPart.Image is being set correctly (ie is an instance of WinPhone8ImageProvider ).

Answer 1

It turns out this was nothing to do with the converter at all. The value was binding before the image had loaded (so the source was empty). For future reference check to make sure you are implementing the INotifyPropertyChanged correctly in your view models.