Skip to main content

WP7Contrib: Updated version of SilverlightSerializer

Mike Talbot's release a new version of SilverlightSerializer - keep up the great work!

Mike's blog can be found here with a list of the improvements for v2.

Obviously a performance improvement is always welcomed especially on a mobile device, but for me the biggest change is the friendly exception message support he's added. Several people using the WP7Contrib had said it was difficult to debug serialisation issues when using the Isolated Cache Provider because when it threw an exception invariably it would be the 'MissingMethodException'. At best this was a good pointer to problems with serialisation at worst it gave no really indication of where to look.

So the previous version (v1) gave the following output for the Cache Provider demo in the WP7Contrib Spikes directory, when the Isolated Cache Provider is attempting to serialize the cache contents (to isolated storage on a background thread) it's throwing the 'MissingMethodException' exception. This is because I've not added the WP7Contrib Serialization Helper assembly to the collection of external assemblies registered with the SilverlightSerializer.


So after compiling the new version of SilverlightSerializer for Windows Phone (I had do this manually after getting the code from GitHub) we get the following output.


Notice the exception details, it details the type failing serialisation - 'System.Uri'. It even goes as far to state the reason - the type does not have a parameterless constructor.

So to get this working as stated above we add the WP7Contrib Serialization Helper assembly to the collection of external assemblies registered with the SilverlightSerializer via the Isolated Cache Provider, see below:


That pretty much covers it.

I've got a blog post coming about the supported I've added to the Cache Provider Interface for checking type are serializable via a method called 'IsCacheable' this will allow you to check types are suitable for caching when writing unit tests.


Labels:

Comments

Post a Comment

Popular posts from this blog

Implementing a busy indicator using a visual overlay in MVVM

This is a technique we use at work to lock the UI whilst some long running process is happening - preventing the user clicking on stuff whilst it's retrieving or rendering data. Now we could have done this by launching a child dialog window but that feels rather out of date and clumsy, we wanted a more modern pattern similar to the way <div> overlays are done on the web. Imagine we have the following simple WPF app and when 'Click' is pressed a busy waiting overlay is shown for the duration entered into the text box. What I'm interested in here is not the actual UI element of the busy indicator but how I go about getting this to show & hide from when using MVVM. The actual UI elements are the standard Busy Indicator coming from the WPF Toolkit : The XAML behind this window is very simple, the important part is the ViewHost. As you can see the ViewHost uses a ContentPresenter element which is bound to the view model, IMainViewModel, it contains 3 child v
Post a Comment
Read more

Showing a message box from a ViewModel in MVVM

I was doing a code review with a client last week for a WPF app using MVVM and they asked ' How can I show a message from the ViewModel? '. What follows is how I would (and have) solved the problem in the past. When I hear the words ' show a message... ' I instantly think you mean show a transient modal message box that requires the user input before continuing ' with something else ' - once the user has interacted with the message box it will disappear. The following solution only applies to this scenario. The first solution is the easiest but is very wrong from a separation perspective. It violates the ideas behind the Model-View-Controller pattern because it places View concerns inside the ViewModel - the ViewModel now knows about the type of the View and specifically it knows how to show a message box window: The second approach addresses this concern by introducing the idea of messaging\events between the ViewModel and the View. In the example below
5 comments
Read more

Custom AuthorizationHandler for SignalR Hubs

How to implement IAuthorizationRequirement for SignalR in Asp.Net Core v5.0 Been battling this for a couple of days, and eventually ended up raising an issue on Asp.Net Core gitHub  to find the answer. Wanting to do some custom authorization on a SignalR Hub when the client makes a connection (Hub is created) and when an endpoint (Hub method) is called:  I was assuming I could use the same Policy for both class & method attributes, but it ain't so - not because you can't, because you need the signatures to be different. Method implementation has a resource type of HubInnovationContext: I assumed class implementation would have a resource type of HubConnectionContext - client connects etc... This isn't the case, it's infact of type DefaultHttpContext . For me I don't even need that, it can be removed completely  from the inheritence signature and override implementation. Only other thing to note, and this could be a biggy, is the ordering of the statements in th
Post a Comment
Read more