Question

How do I bind a bool to select a specific image? For eg. I have My Image control. I have a binded property with the name of IsTrue.

I have 2 images:

1. TrueImg.png
2. FalseImg.png

How do I show an image based on bool?

Then how can I extend this to affect strings, such as “Male”, “Female”?

All images are located inside the silverlight app.

Answer 1

Take a look the blog article A Generic Boolean Value Converter. With the code there in place you add this converter:-

 public class BoolToBitmapImageConverter : BoolToValueConverter<BitmapImage> { }

Now add an instance of this to your Xaml:-

 <UserControl.Resource>
     <local:BoolToBitmapImageConverter x:Key="boolImgConv" >
         <local:BoolToBitmapImageConverter.TrueValue>
             <BitmapImage UriSource="TrueImg.png" />
         </local:BoolToBitmapImageConverter.TrueValue>
         <local:BoolToBitmapImageConverter.FalseValue>
             <BitmapImage UriSource="FalseImg.png" />
         </local:BoolToBitmapImageConverter.FalseValue>
     </local:BoolToBitmapImageConverter>
 </UserControl.Resource>     

Now you can bind using this converter:

 <Image Source="{Binding YourBoolProp Converter={StaticResource boolImgConv}}" />

Similarly you can add a converter for you strings:-

 <local:BoolToStringConverter x:Key="boolSex" FalseValue="Male" TrueValue="Female" />

and:-

 <TextBlock Text="{Binding YouBoolProp Converter={StaticResource boolSex}}" />