NInject IBindingGenerator and ToProvider - ninject

Question

I've created this code:
public class AddonsModule : Ninject.Modules.NinjectModule
{
public override void Load()
{
this.Bind(b => b.FromAssembliesMatching("*")
.SelectAllClasses()
.InheritedFrom(typeof(UIExtensibility.AbstractAddon))
.BindWith(new AddonBindingGenerator())
);
}
private class AddonBindingGenerator : IBindingGenerator
{
public System.Collections.Generic.IEnumerable<Ninject.Syntax.IBindingWhenInNamedWithOrOnSyntax<object>> CreateBindings(System.Type type, Ninject.Syntax.IBindingRoot bindingRoot)
{
if (type.IsInterface || type.IsAbstract)
yield break;
yield return bindingRoot.Bind(type).ToProvider(typeof(UIExtensibility.AbstractAddon));
}
}
private class AddonProvider : IProvider<UIExtensibility.AbstractAddon>
{
public object Create(IContext context)
{
return null;
}
public Type Type
{
get { throw new NotImplementedException(); }
}
}
}
AddonProvider seems be avoided. This is never performed.
When I perform:
kernel.GetAll<UIExtensibility.AbstractAddon>(), AddonProvider.Create method is never performed.
Could you tell me what's wrong?
I'll appreciate a lot your help.
Thanks for all.

Answer 1

AddOnProvider is inheriting from IProvider<T> instead of UIExtensibility.AbstractAddon.
also, you may have issues binding to private inner classes. make AddOnProvider a public top level class.

Answer 2

You're binding a specific type which inherits from typeof(UIExtensibility.AbstractAddon) to a provider. For example, there could be a class Foo : UIExtensibility.AbstractAddon.
Now your convention binding translates to this:
Bind<Foo>().ToProvider<AddonProvider>();
Now, kernel.GetAll<UIExtensibility.AbstractAddon>() however is looking for bindings made like:
Bind<UIExtensibility.AbstractAddon>().To...
Fix It
So what you need to do is change the line
bindingRoot.Bind(type).ToProvider(new AddonProvider());
to:
bindingRoot.Bind(typeof(UIExtensibility.AbstractAddon)).ToProvider<AddonProvider>();
Furthermore
you're line object f = bindingRoot.Bind(type).ToProvider(new AddonProvider()); is never returning the binding (object f).
does UIExtensibility.AbstractAddon implement IProvider?

Answer 3

Thanks for your answer and comments.
I believe the trouble is on I'm not quite figuring out how this "generic" binding process works.
I'm going to try writing my brain steps process out:
I need to bind every AbstractAddon implementation inside addons assemblies folder. So, I think this code is right, but I'm not sure at all.
this.Bind(b => b.FromAssembliesMatching("*")
.SelectAllClasses()
.InheritedFrom(typeof(UIExtensibility.AbstractAddon))
.BindWith(new AddonBindingGenerator())
);
My AbstractAddon is like:
public abstract class AbstractAddon : IAddon
{
private object configuration;
public AbstractAddon(object configuration)
{
this.configuration = configuration;
}
// IAddon interface
public abstract string PluginId { get; }
public abstract string PluginVersion { get; }
public abstract string getCaption(string key);
public abstract Type getConfigurationPanelType();
public abstract System.Windows.Forms.UserControl createConfigurationPanel();
}
I guess I need to:
foreach implementation of `AbstractAddon` found out,
I need to "inject" a configuration object ->
So, I guess I need to set a provider and provide this configuration object.
This would be my main way of thinking in order to solve this problem.
I've changed a bit my first approach. Instead of using a IBindingGenerator class, I've used the next:
public class AddonsModule : Ninject.Modules.NinjectModule
{
public override void Load()
{
this.Bind(b => b.FromAssembliesMatching("*")
.SelectAllClasses()
.InheritedFrom(typeof(UIExtensibility.AbstractAddon))
.BindAllBaseClasses()
.Configure(c => c.InSingletonScope())
);
this.Bind<object>().ToProvider<ConfigurationProvider>()
.WhenTargetHas<UIExtensibility.ConfigurationAttribute>();
}
So, My ConfigurationProvider is:
private class ConfigurationProvider : IProvider<object>
{
public object Create(IContext context)
{
return "configuration settings";
}
}
And now, my AbstractAddon constructor contains the parameter annotated with ConfigurationAttribute as:
public AbstractAddon([Configuration]object configuration)
{
this.configuration = configuration;
}
The problem now, NInject seems to ignore the configuration object provider. NInject generates a dump object, however, not perform ConfigurationProvider.Create method...
What I'm doing wrong, now?
Is this approach really better than the last one?
Thanks for all.