I'm currently registering a bunch of stuff at one point in my initialisation sequence
Container.Register(AllTypes.FromAssemblyContaining<MyAssembly>()
.BasedOn(typeof(IRepository<>))
.WithService.Self().Configure(c => c.LifeStyle.Transient));
I'm using WithService.Self so that it doesn't automatically pick up AllInterfaces, so that the interface that I will want to add later on as a type forward has not already been added.
I'd like then (later on) to be able to add a type forward to one of the already registered components, and Intellisense on the ForwardedTypes property suggested using .Forward(typof()) e.g.
Container.Register(Component.For<IOtherInterface>()
.Forward(typeof(IOtherInterface))
.ImplementedBy<AlreadyRegisteredType>().LifeStyle.Transient);
Is this possible?
EDIT:
I've been trying to get the stuff that Krzysztof has suggested working so I've generated a test project (below). I've tried various combinations to get the ConfigureFor to forward IMyInterface to MySecondType, but just can't get it to work, when done as a second step after initial registration of my component types. I'm probably being dim, but I'm just not getting how the ConfigureFor command works, and the documentation is a little sketchy (non-existant) on the subject.
namespace TestProject1
{
public class MyType : IMyInterface
{
public virtual string MyProperty { get; set; }
}
public class MySecondType : IMyInterface
{
public virtual string MySecondProperty { get; set; }
}
public interface IMyInterface
{
}
[TestClass]
public class UnitTest1
{
[TestMethod]
public void TestMethod1()
{
//New Container
var container = new WindsorContainer();
//Register Types
container.Register(
AllTypes.FromAssemblyContaining<MyType>().BasedOn<IMyInterface>().WithService.Self().Configure(
c => c.LifeStyle.Transient));
//Other stuff happens here...
//Now Register our interface as a forward
container.Register(AllTypes.FromAssemblyContaining<IMyInterface>()
.BasedOn<IMyInterface>()
.WithService.Base()
.ConfigureFor<IMyInterface>(r => r.Forward<MySecondType>()).Configure(c => c.LifeStyle.Transient));
var typeA = new MySecondType();
var typeB = container.Resolve<IMyInterface>();
Assert.IsInstanceOfType(typeB.GetType(), typeA.GetType());
}
}
}
What you described in the comment is registering another component for the AlreadyRegisteredType.
If you want to add a forward to the same component use
ConfigureFor<AlreadyRegisteredType>(c => c.Forward<IOtherInterface>())
full example:
Container.Register(AllTypes.FromThisAssembly()
.BasedOn<IEmptyService>()
.WithService.Base()
.ConfigureFor<EmptyServiceComposite>(r => r.Forward<EmptyServiceComposite>()));
Once you registered some type
Container.Register(Component.For<SomeType>());
you can forward some interface to it in this way:
Container.Register(Component.For<ISomeInterface>()
.UsingFactoryMethod<ISomeInterface>(kernel => kernel.Resolve<SomeType>()));
Related
Although I'm relatively new to AutoMapper I'm using it in a small project I'm developing. I've never had problems using it before but now I'm facing some weird behavior passing parameters to a Custom Resolver.
Here's the scenario: I get a list of messages from my repository and then map those to a frontend friendly version of it. Nothing fancy, just some normal mapping between objects. I have a field in that frontend object that tells if a certain user already voted for that message and that's what I'm using the Custom Resolver for (it's that second "ForMember"):
public List<SupportMessageUi> GetAllVisible(string userId)
{
Mapper.CreateMap<SupportMessage, SupportMessageUi>()
.ForMember(dest => dest.Votes,
opt => opt.ResolveUsing<SupportMessageVotesResolver>())
.ForMember(dest => dest.UserVoted,
opt => opt.ResolveUsing<SupportMessagesUserVotedResolver>()
.ConstructedBy(() => new SupportMessagesUserVotedResolver(userId)));
var messages = _unitOfWork.MessagesRepository.Get(m => m.Visible);
var messagesUi = Mapper.Map<List<SupportMessageUi>>(messages);
return messagesUi;
}
I'm calling this method on a web service and the problem is: the first time I call the webservice (using the webservice console) it all runs perfectly. For example, if I pass '555' as the userId I get to this method with the correct value:
And in the Custom Resolver the value was correctly passed to the constructor:
The results returned are correct. The problem comes next. The second time I call the service, passing a different argument ('666' this time) the argument that gets to the constructor of the Custom Resolver is the old one ('555'). Here's what I mean:
Right before mapping the objects we can see that the value passed to the constructor was correct ('666'):
But when it gets to the constructor of the Resolver the value is wrong, and is the old one ('555'):
All subsequent calls to the service use the original value in the Custom Resolver constructor ('555'), independently of the value I pass to the service (also happens if I make the call from another browser). If I shut down the server and relaunch it I can pass a new parameter (that will be used in all other calls until I shut it down again).
Any idea on why this is happening?
It's happening because AutoMapper.CreateMap is a static method, and only needs to be called once. With the CreateMap code in your web method, you're trying to call it every time you call that method on your web service. Since the web server process stays alive between calls (unless you restart it, like you said) then the static mappings stay in place. Hence, the necessity of calling AutoMapper.Reset, as you said in your answer.
But it's recommended that you put your mapping creation in AppStart or Global or a static constructor or whatever, so you only call it once. There are ways to call Map that allow you to pass in values, so you don't need to try to finesse things with the constructor of your ValueResolver.
Here's an example using a ValueResolver (note the change to implementing IValueResolver instead of inheriting ValueResolver<TSource, TDestination>):
[Test]
public void ValueTranslator_ExtraMapParameters()
{
const int multiplier = 2;
ValueTranslator translator = new ValueTranslator();
Mapper.AssertConfigurationIsValid();
ValueSource source = new ValueSource { Value = 4 };
ValueDest dest = translator.Translate(source, multiplier);
Assert.That(dest.Value, Is.EqualTo(8));
source = new ValueSource { Value = 5 };
dest = translator.Translate(source, multiplier);
Assert.That(dest.Value, Is.EqualTo(10));
}
private class ValueTranslator
{
static ValueTranslator()
{
Mapper.CreateMap<ValueSource, ValueDest>()
.ForMember(dest => dest.Value, opt => opt.ResolveUsing<ValueResolver>().FromMember(src => src.Value));
}
public ValueDest Translate(ValueSource source, int multiplier)
{
return Mapper.Map<ValueDest>(source, opt => opt.Items.Add("multiplier", multiplier));
}
private class ValueResolver : IValueResolver
{
public ResolutionResult Resolve(ResolutionResult source)
{
return source.New((int)source.Value * (int)source.Context.Options.Items["multiplier"]);
}
}
}
private class ValueSource { public int Value { get; set; } }
private class ValueDest { public int Value { get; set; } }
And here's an example using a TypeConverter:
[Test]
public void TypeTranslator_ExtraMapParameters()
{
const int multiplier = 3;
TypeTranslator translator = new TypeTranslator();
Mapper.AssertConfigurationIsValid();
TypeSource source = new TypeSource { Value = 10 };
TypeDest dest = translator.Translate(source, multiplier);
Assert.That(dest.Value, Is.EqualTo(30));
source = new TypeSource { Value = 15 };
dest = translator.Translate(source, multiplier);
Assert.That(dest.Value, Is.EqualTo(45));
}
private class TypeTranslator
{
static TypeTranslator()
{
Mapper.CreateMap<TypeSource, TypeDest>()
.ConvertUsing<TypeConverter>();
}
public TypeDest Translate(TypeSource source, int multiplier)
{
return Mapper.Map<TypeDest>(source, opt => opt.Items.Add("multiplier", multiplier));
}
private class TypeConverter : ITypeConverter<TypeSource, TypeDest>
{
public TypeDest Convert(ResolutionContext context)
{
TypeSource source = (TypeSource)context.SourceValue;
int multiplier = (int)context.Options.Items["multiplier"];
return new TypeDest { Value = source.Value * multiplier };
}
}
}
private class TypeSource { public int Value { get; set; } }
private class TypeDest { public int Value { get; set; } }
Answering myself: I was not using AutoMapper.Reset(). Once I did that everything started working properly.
Helpful reading: http://www.markhneedham.com/blog/2010/01/27/automapper-dont-forget-mapper-reset-at-the-start/
To share data (complexe data ) between pages in my windows phone 8 application I want to implement a singleton, but I want it to be generic, is it possible? I suppose that it creates a new instance for each type isn't it?
public sealed class NavigationContextService<T>
{
private static readonly NavigationContextService<T> instance = new NavigationContextService<T>();
private NavigationContextService()
{
}
public static NavigationContextService<T> Instance
{
get
{
return instance;
}
}
public List<T> ShareList { get; set; }
public T ShareData { get; set; }
}
It is creating a new instance for every type, because it is generic - you want it to be like this (if you start with generics, take a look at some tutorials, blogs or MSDN - you will easily find many in the internet).
It is still a singleton. When you use
NavigationContextService<string>.Instance.ShareList.Add("Text");
then you have one Instance for type string. Generics helps a lot when you want to create same methods/classes that differ in type.
On the other hand if you want to create Singleton that will hold different types then you can for example modify your class to be non Generic like this:
public sealed class NavigationContextServiceNonGeneric
{
private static readonly NavigationContextServiceNonGeneric instance = new NavigationContextServiceNonGeneric();
private NavigationContextServiceNonGeneric() { ShareList = new List<object>(); }
public static NavigationContextServiceNonGeneric Instance
{ get { return instance; } }
public List<object> ShareList { get; set; }
public object ShareData { get; set; }
}
As you can see in the code above I haven't defined the 'exact' type of shared data - it is object type. Then you can easily hold most of data with it:
NavigationContextServiceNonGeneric.Instance.ShareList.Add("Text");
NavigationContextServiceNonGeneric.Instance.ShareList.Add(3);
NavigationContextServiceNonGeneric.Instance.ShareList.Add(3.0f);
It is singleton, which can hold different types of shared data. BUT it has also disavantages - the main is that you have to remember what type of data you hold and in what order. In my opinion Generic version is better because of that fact.
Everything depends on the purpose of your code. There may be easier and better ways that those two approaches.
As for the Page Navigation, you can for example try to use a method from this article - you extend Navigation service to pass the object:
public static class Extensions
{
private static object Data;
public static void Navigate(this NavigationService navigationService, Uri source, object data)
{
Data = data;
navigationService.Navigate(source);
}
public static object GetNavigationData(this NavigationService service) { return Data; }
}
Then you use it:
NavigationService.Navigate(yourUri, DataToPass);
After Navigation you can get your data:
string myTextData = NavigationService.GetNavigationData() as string;
This method has to disadvantages: it is not type-safe and your data won't be preserved in Tombstone mode.
As for the second disadvantage you can easily use PhoneApplicationService.State Property for the purpose of Page Navigation - it is a dictionary (which is preserved while tombstoning):
PhoneApplicationService.Current.State.Add("data", yourData);
Then when you want to get your data:
yourDataType yourData = PhoneApplicationService.Current.State["data"] as yourDataType;
There are also more ways in which you can pass the data.
In v3 if I wanted to pass two objects to another viewmodel:
public class Dog
{
}
public class Cat
{
}
var dog = new Dog();
var cat = new Cat();
ShowViewModel<SomeViewModel>(new {Dog = dog, Cat = cat });
public class SomeViewModel
{
Init(Dog dog, Cat cat)
{
}
}
As far as I can tell that won't work because the types aren't recognized and can't be stuck in a dictionary. If I wanted to have these serialized as json, passed to the view model, and deserialized as Init parameters, would I implement IExtraParser? And if that is correct, how do I go about adding the implementations to the ExtraParsers dictionary?
update:
This seems to do it:
var foo = Mvx.Resolve<IMvxFillableStringToTypeParser>();
foo.ExtraParsers.Add(new MyParser());
The default navigation mechanism in MvvmCross is deliberately lightweight.
It is really there to allow you to pass just one simple, serializable object - e.g.
public class DogNav
{
public int Id {get;set;}
public string Caption {get;set;}
}
// received in:
public class DogViewModel : MvxViewModel
{
public void Init(DogNav dogNav)
{
}
}
With this setup, if a navigation is triggered like:
// navigation
ShowViewModel<DogViewModel>(new DogNav() { Id=12, Caption="Good boy" });
then the underlying system will transport the values from that DogNav object - possibly using Uris, Intents or other serialization techniques - to the new DogViewModel and will then ensure Init is called with the correct values.
Because of the serialization, it's important:
not to pass big objects (Uris on WindowsPhone can break above a few hundred characters)
not to expect the same object instance to arrive - i.e. if you are using database-backed or stateful objects, then it's best to pass some kind of lookup key rather than the objects themselves.
not to expect that only one ViewModel will receive the message - on some operating systems, it may be that the user goes back and forth many, many times between apps causing many Views and ViewModels to be created.
not to expect that a ViewModel that receives the message is in the same process and memory space as the ViewModel that sent the request - the same may actually be received days later after a tombstoning event.
If you do want to pass multiple objects via navigation, then I think you can do this using code like:
public class CatNav
{
public int CatId {get;set;}
public string CatCaption {get;set;}
}
public class DogNav
{
public int DogId {get;set;}
public string DogCaption {get;set;}
}
// received in:
public class CatAndDogViewModel : MvxViewModel
{
public void Init(DogNav dogNav)
{
}
public void Init(CatNav catNav)
{
}
}
In this case you could navigate using:
var catNav = new CatNav() { CatId =12, CatCaption="Meow" };
var dogNav = new DogNav() { DogId =12, DogCaption="Woof" };
var bundle = new MvxBundle();
bundle.Write(catNav);
bundle.Write(dogNav);
ShowViewModel<CatAndDogViewModel>(bundle);
I think this would work...
However... please be aware that the serialization is very simple - so if CatNav and DogNav were to share a property name, then this would lead to problems - you'd end up with some Cags and Dots
Because of the Cag and Dot problem I don't recommend this approach...
If you do need more complex transitions in your apps, then one route is to:
UPDATE - see Passing complex navigation parameters with MvvmCross ShowViewModel
1. Add the Json Plugin (or any Json serializer) and change your Setup.cs code to create a MvxJsonNavigationSerializer - overriding CreateNavigationSerializer
protected override IMvxNavigationSerializer CreateNavigationSerializer()
{
return new MvxJsonNavigationSerializer();
}
Use a composite object in navigation like:
public class DogAndCatNav
{
public DogNav DogNav {get;set;}
public CatNav CatNav {get;set;}
}
This would be received by:
public void Init(DogAndCatNav dogAndCatNav)
{
}
But note that this technique does need a more powerful serialization engine - such as Json.
Overall... even after writing all this... I'd recommend you pass as little data as possible in your navigations!
public class A
{
public X x { get; set; }
}
public class B
{
public X x { get; set; }
}
public class X
{
public X(object owner) { /* ... */ }
}
Basically if classes A and B are registered in Windsor I want to be able to resolve X dependency in such a way that it gets instance of the class it was required for.
In plain code it would look like that:
var a = new A();
var x = new X(a);
a.X = x;
Is there a way to do this in Windsor, maybe through some extensibility mechanism?
It looks like some crazy question even for me, so here is some motivation behind it:
The X in the example above is ITracer which is a proxy for TraceSource that is adding some bits of info to each traced message, namely, unique ID of the owner and its type (now it is only ID - that's why the question - I can't get to the instance and call GetType() on it).
A brief example to make it more clear. Suppose you have some service IService and want to add traces to it in the most non-intrusive way. But in the application could be dozen of instances of this service, so in traces you want to distinguish them by ID/type. It would be good if class received its tracer from the container and just wrote messages there when needed, without thinking of IDs, concrete TraceSource etc.
I already have some infrastructure that allows me to write like that:
[TracedTo("NameOfTheTraceSource")]
public class Service : IService
{
public ITracer Tracer { get; set; }
}
And Windsor correctly resolves Tracer to be its own (non-shared with other objects) instance of ITracer pointing to TraceSource with name NameOfTheTraceSource. Moreover, if I add traceAllMethods = true to the attribute - Windsor will automatically add interceptor which will write down each method call on this instance via the same Tracer (and only does this if corresponding TraceSource has some listeners configured - we don't have to support adding them on the fly). This is just awesome because it doesn't require anything from the developer of Service and it doesn't suffer performance degradation when it is not needed, not a bit. And so I'm working to make this even more convenient :)
OK, I think what you want here is a facility. Here's a simple one (with no error checking) that may be what you're looking for (or at least point you in the right direction):
public class XFacility : AbstractFacility
{
protected override void Init()
{
this.Kernel.ComponentCreated += KernelOnComponentCreated;
}
private void KernelOnComponentCreated(ComponentModel model, object instance)
{
var props =
instance.GetType().GetProperties().Where(p => p.CanWrite && p.PropertyType == typeof (X));
if (props.Any())
{
var pi = props.First();
pi.SetValue(instance, new X(instance), null);
}
}
}
Now make sure you add the facility to the container before you do any resolving:
var container = new WindsorContainer();
container.AddFacility<XFacility>();
container.Register(Component.For<A>(),
Component.For<B>()
);
var a = container.Resolve<A>();
I have a group of classes that implement an interface for my application start-up activities. Here is the registration code:
private static void ConfigureContainer()
{
var container = new WindsorContainer();
container.Register(AllTypes.Of<IStartupTask>()
.FromAssembly(Assembly.GetExecutingAssembly()))
...
var serviceLocator = container.Resolve<IServiceLocator>();
ServiceLocator.SetLocatorProvider(() => serviceLocator);
}
In order to get the tasks, I use this and it works as expected:
public static void Run()
{
var tasks = ServiceLocator.Current.GetAllInstances<IStartupTask>();
foreach (var task in tasks)
{
task.Execute();
}
}
Here is my problem: I have one task that depends on another being run first. There is an InitializeDatabase task that needs to run before the PopulateDatabse task. There are also a bunch of other tasks that are run and I would rather not split the InitializeDatabase task out, if there is some Castle config that will allow me to order the resolution of the types. I don't want to specify the complete order of the types being resolved since that defeats the purpose of the automatic registration, just that InitializeDatabase is the first or PopulateDatabase is last.
Is there a way to register which types should be resolved first without specifying the order of all the types?
Here's one way to do it, it might not be very pretty but it works:
[AttributeUsage(AttributeTargets.Class)]
public class FirstAttribute: Attribute {}
public interface IService {}
public class ThirdService : IService { }
[First]
public class FirstService : IService { }
public class SecondService: IService {}
[Test]
public void WindsorOrder() {
var container = new WindsorContainer();
container.Register(AllTypes.Of<IService>()
.FromAssembly(Assembly.GetExecutingAssembly()));
var intf = container.ResolveAll<IService>()
.OrderByDescending(i => i.GetType().GetCustomAttributes(typeof(FirstAttribute), true).Length)
.ToArray();
Assert.IsInstanceOfType(typeof(FirstService), intf[0]);
}
If you remove [First] from FirstService, the first will be ThirdService and the test will fail.
Use HandlerSelector for that