Question

I would like my elements generated from datatemplate to look differently depending on some properties in the model. For example I want to display the text in various colors or present different images or path drawing for each generatred element. I know how to do it in general, but I’m looking for a solution that would allow editing the visual details in Expression Blend by designer without touching the code. For example the simplest solution:

   <DataTemplate>
        <StackPanel Orientation="Horizontal"> 
            <Image Source="{Binding MyImageSource}"/>
            <TextBlock Width="200"  Text="{Binding MyText}" Forecolor="{Binding MyColor}"></TextBox> 
        </StackPanel> 
    </DataTemplate> 

Where ‘MyImageSource’ and ‘MyColor’ are properties of the item model (of type ImageSource and Brush) does not satisfy my needs because I don’t want to assign these values. I want the designer to do that. Instead of ‘MyImageSource’ and ‘MyColor’ properties my model would have a property like ‘ItemType’ or ‘ItemStyle’ of type enum or string (or some other type). I’m not looking for “religious” MVVM strict solution. My only requirement is to avoid the need for the designer to wait for me to correct the code following his instructions like “change the item color of type X in list Y to #FFAACC” because it seems like breaking the SoC rule in a way.

EDIT (based on the answers):

I’ve found similar solution to the one described by bendewey here – it requires to derive custom control for the control using ItemsSource attribute. The idea of using different datatemplates for each element type is neat, but in my opinion it covers the situation when we want to generate completely different visual elements for each item. When the elements differ only in some colors and image (and contain lots of common elements apart from that), then creating separate datatemplate for each element type would cause unnecessary code (xaml) repetition. In this situation Vlad’s solution suits better.
Is there any other technique apart from theese two?

Answer 1

You can use converters. Foe example, Forecolor="{Binding MyText, Converter=ColorFromText}.
You would need to store color-picking logic into the converter.