Silverlight honors the protection that helps mitigate a sites scripts from being called if someone simply copied your app to their server. 

The error you get is this: 

An error occurred while trying to make a request to URI ‘http://localhost.:2935/Services/UserService.svc’. This could be due to attempting to access a service in a cross-domain way without a proper cross-domain policy in place, or a policy that is unsuitable for SOAP services. You may need to contact the owner of the service to publish a cross-domain policy file and to ensure it allows SOAP-related HTTP headers to be sent. This error may also be caused by using internal types in the web service proxy without using the InternalsVisibleToAttribute attribute. Please see the inner exception for more details. 

This error is very easily fixed. 

Create a file in you web root. Must be the root called clientaccesspolicy.xml . It must be named exactly and must live in the root. 

File: clientaccesspolicy.xml

Now, copy this into the file: 

<?xml version="1.0" encoding="utf-8"?>
<access-policy>
  <cross-domain-access>
    <policy>
      <allow-from http-request-headers="SOAPAction">
        <domain uri="*"/>
      </allow-from>
      <grant-to>
        <resource path="/" include-subpaths="true"/>
      </grant-to>
    </policy>
  </cross-domain-access>
</access-policy>

Save it, rebuild and run. Voila, you should now be up and running. If you need more info, check this helpful link. 

Happy Coding!

So you turn on Fiddler, but no requests appear? Well, some strange issues, with a long explanation, about using localhost don’t get logged into Fiddler. The trick is to rename your service references to localhost. Yes, simply add the .

Just make sure you type that URL the same way into your browser, otherwise you get a cross domain call issue. That is the subject for the next quick post.

Happy coding!

Well, simple solution to an annoying problem. Use the converter below on your binding and it becomes opposite day.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows.Data;
 
namespace Seekford{
    public class BooleanNotConverter : IValueConverter
    {
        //easy peezy.
 
        /// <summary>
        /// Converts a value.
        /// </summary>
        /// <param name="value">The value produced by the binding source.</param>
        /// <param name="targetType">The type of the binding target property.</param>
        /// <param name="parameter">The converter parameter to use.</param>
        /// <param name="culture">The culture to use in the converter.</param>
        /// <returns>
        /// A converted value. If the method returns null, the valid null value is used.
        /// </returns>
        public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            return !(bool)value;
        }
 
        /// <summary>
        /// Converts a value.
        /// </summary>
        /// <param name="value">The value that is produced by the binding target.</param>
        /// <param name="targetType">The type to convert to.</param>
        /// <param name="parameter">The converter parameter to use.</param>
        /// <param name="culture">The culture to use in the converter.</param>
        /// <returns>
        /// A converted value. If the method returns null, the valid null value is used.
        /// </returns>
        public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            return !(bool)value;
        }
 
        
    }
}

Happy Coding!

Please check out this great article. The source code is at the bottom of the article. You just need to extract the classes out and put into your own project. Took me about 5 minutes.

http://blog.thekieners.com/2010/09/08/relativesource-binding-with-findancestor-mode-in-silverlight/

I am testing it out more tonight, but seems to do the trick. So much nicer to now have my item template be able to reach the parent context.

Oh, and he even made the greatest simple addition. It has the built in feature to auto search for the nearest DIFFERENT datacontext. How great is that? Makes the xaml def even easier to write.

Happy coding!

Anyway, I was just about to write my own behavior when I found this one. It was written for Silverlight 3 but works fine in Silverlight 4.

Check out his article, much more detailed than I would write.

 http://dnchannel.blogspot.com/2010/01/silverlight-3-auto-select-text-in.html

Happy Coding!

I had it setup correctly, but why would the system not compile it?

This was the registration:

<add name="silverlightFaults"
type="Seekford.SilverlightFaultBehavior.SilverlightFaultBehavior,Seekford.SilverlightFaultBehavior, Version=1.0.0.0, Culture=neutral, PublicKeyToken=7073c134a4dabf61" />

So? What is wrong with this picture? Nothing unless you are an unforgiving parse engine that exists to make life difficult.

I had to add a space. Yes, a space between the class and assembly name and BAM!, it worked.

<add name="silverlightFaults"
type="Seekford.SilverlightFaultBehavior.SilverlightFaultBehavior, Seekford.SilverlightFaultBehavior, Version=1.0.0.0, Culture=neutral, PublicKeyToken=7073c134a4dabf61" />

What a pile of #$%!!

Anyway, remember your spacing.

Happy Coding!

I opened the DateTimePicker template and voila! The tard who made such a nice control set the error template to sit next to the TextBox instead of the Button.

Simple fix. Just generate the  DateTimePicker template (Expression Blend) and change the following section:
i.e. Search for ToolTipService.ToolTip

<ToolTipService.ToolTip>
<ToolTip x:Name="validationTooltip" Template="{StaticResource CommonValidationToolTipTemplate}" Placement="Right" PlacementTarget="{Binding ElementName=Button}" DataContext="{Binding RelativeSource={RelativeSource TemplatedParent}}">
<ToolTip.Triggers>
<EventTrigger RoutedEvent="Canvas.Loaded">
<BeginStoryboard>
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="validationTooltip" Storyboard.TargetProperty="IsHitTestVisible">
<DiscreteObjectKeyFrame KeyTime="0">
<DiscreteObjectKeyFrame.Value>
<System:Boolean>true</System:Boolean>
</DiscreteObjectKeyFrame.Value>
</DiscreteObjectKeyFrame>
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</BeginStoryboard>
</EventTrigger>
</ToolTip.Triggers>
</ToolTip>
</ToolTipService.ToolTip>

Using Change the above to Button instead of TextBox. Super easy!

Happy Coding!

Here is a simple extension class to put into your infrastructure. Enjoy!

using System;
using System.IO;
using System.Xml.Serialization;

namespace Seekford.Extensions
{
public static class ObjectCopyMachine
{
/// <summary>
/// Extension to perform a deep Copy of the object specified.
/// </summary>
/// <typeparam name="T">The type of object being copied.</typeparam>
/// <param name="source">The object instance to copy.</param>
/// <returns>The copied object.</returns>
public static T Clone<T>(this T source)
{
if (!typeof(T).IsSerializable)
{
throw new ArgumentException("The type must be serializable.", "source");
}

// Don't serialize a null object, simply return the default for that object
if (Object.ReferenceEquals(source, null))
{
return default(T);
}
XmlSerializer serializer = new XmlSerializer(source.GetType());
Stream stream = new MemoryStream();
using (stream)
{
serializer.Serialize(stream, source);
stream.Seek(0, SeekOrigin.Begin);
return (T)serializer.Deserialize(stream);
}
}
}
}

Now you can just call any object and say. Abracadabra……      myObject.Clone();

Happy Coding!

The main hurdle that was annoying me was having to change the endpoint the Silverlight application was pointing by editing a configuration file that was embedded in the application. Mainly, the fact that this required a recompile when going from local build to server. What a pain!!! Bad Microsoft…Bad..

I decided to just write a simple addition to my factory to generate the endpoints on the fly, no more recompile per site required. This also lets the application easily be moved server to server without any pains. Relative WCF URLS should have been a mandatory addition, but alas their not. If Microsoft had thought of everything, I wouldn’t have a job I guess.

Here is the simple code to do a dynamic endpoint in Silverlight. Enjoy!

using System;
using System.ServiceModel;
using System.ServiceModel.Channels;
using System.Windows;

namespace Seekford.Repository.MyServices
{
    internal class MyServiceFactory
    {
        private const string myServiceLocation = "../Services/MyCService.svc";

        /// <summary>
        /// Creates the binding.
        /// </summary>
        /// <returns></returns>
        private static CustomBinding CreateBinding()
        {
            CustomBinding binding = new CustomBinding();
            binding.Name = "SilverlightBindingGoodTimes";
           binding.Elements.Add(new BinaryMessageEncodingBindingElement());
            binding.Elements.Add(new HttpTransportBindingElement()
                {
                    MaxBufferSize = int.MaxValue,
                    MaxReceivedMessageSize = int.MaxValue
                }
            );

            binding.OpenTimeout = new TimeSpan(0, 5, 0);
            binding.CloseTimeout = new TimeSpan(0, 5, 0);
            binding.ReceiveTimeout = new TimeSpan(0, 5, 0);
            binding.SendTimeout = new TimeSpan(0, 5, 0);         

            return binding;
        }

        /// <summary>
        /// Creates the aand C service client.
        /// </summary>
        /// <returns></returns>
        public static MyServiceClient CreateMyServiceClient()
        {
            var binding = CreateBinding();
            return new MyServiceClient (binding, new EndpointAddress(
                new Uri(Application.Current.Host.Source, myServiceLocation )));
        }       

    }
}

You will obviously need to tailor to your needs, but the idea is pretty straight forward.

Happy coding!

<Grid>
<Grid.RowDefinitions>
        <RowDefinition Height="Auto" />
        <RowDefinition Height="4" /> <!-- Look ma, padding -->
        <RowDefinition Height="Auto" />
</Grid.RowDefinitions>
.....
</Grid>