I have created sample WindowsRunTimeComponent app in windows 8, with one property my class looks like..
namespace WindowsRunTimeComponentTest
{
public sealed class Class1
{
public NetworkCredential Credentials {get; set;}
}
}
when I tried to build this, its giving error :
Method 'WindowsRunTimeComponentTest.class1.Credentials.get()' returns System.Net.Credentials', which is not a valid Windows Runtime type. Methods exposed to Windows Runtime must return only Windows Runtime types.
I have vs2012.
please any idea what I have to change to resolve this issue?
My best guess is, when you create a Windows Runtime Component, your component can be used by languages that are not managed, like Javascript or C++.
Those languages don't know how to create specific .NET types such as NetworkCredentials.
For more info see the MSDN documentation here and this stackoverflow post.
Related
I have a Windows Phone 8.1 app in VS2015.
I am trying to add a property to my model that is not saved to the database. However, when I try to use the [NotMapped] annotation, I get the error:
The type or namespace name 'NotMapped' could not be found
I then added this using statement and tried to add it as a reference to the project. But apparently, I need to change my targetFramework in order to use this reference.
using System.ComponentModel.DataAnnotations.Schema;
Can a WP 8.1 app use the [NotMapped] annotation like below? Or is this not allowed in a WP app?
[NotMapped]
public double MyColumnName { get; set; }
The NotMappedAttribute is not available on Windows Phone 8.1.
Universal Windows Platform
Available since 10
.NET Framework
Available since 4.5
Source: MSDN
As Entity Framework is not available on Windows Phone 8.1, it's no use trying to use data annotations on the client. You'll have simple DTO classes on the client and more extensive models on the server backend where data-access to your database is handled. Converting between these 2 types can be done easily with tools like AutoMapper.
If you want to have some database on the WP client, you'll have to fall back to one of these options:
SQL CE
SQLite
Any other file based storage (json, xml, document based databases)
I have one Windows Handheld device application which has the requirement of accessing a REST API. The REST API gives me JSON output which I am going to handle via Newton.JSON. Now to achieve modular structure I want to have the communication to the REST API be handled via a different module altogether something like a Class Library. But unfortunately it seems that it is not possible to do so via a class library(or maybe possible). So my question is what is the best alternative to do so?
Please note that I don't want to include those connectivity operations in my front end application project. And I am using .Net framework 3.5 & Windows Mobile SDK 6.0
Thanks in advance
Pseudo class library code:
public function void startQuery() //starts a thread that does the JSON query
//inside thread on query result use OnDone() delegate
private delegate void OnDone(string dateTimeString);
//In main GUI code add a reference to the class lib and init a new object then add an event handler to the OnDone delegate of the class lib
JSONClassLib myJson=new JSONClassLib();
...
myJson.OnDone+=new EventHandler(myEventHandler);
void myEventHandler(sender this, objext o){
//will be called when query is done
}
//you need to use Control.Invoke if you want to update the GUI from myEventHandler
//to start a query use something like this from your class lib
myJson.doQuery(string);
If you add your existing code we may help with creating a class lib and async code
Now I got my answer. Sorry I did a mistake while selecting the project type. I selected "Windows Form Class Library" project instead of "Smart Device Class Library" project. Now that I have selected the right one it is working fine for me.
BTW thanks for those responses.
Cheers
I have an MVVM Light infrastructure which is all contained within a Portable Class Library targeting .Net 4, SL5, Win 8, WP 8.1, WPSL 8, Xamarin.Android and Xamarin.iOS. This works perfectly with a WPF client, however, when I try and use it in a Windows Store App/Win 8 environment I am coming up against some resistance. The first issue is found in App.xaml:
<Application
x:Class="Win8Client.App"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:vm="using:INPS.Vision.Appointments.Shared.ViewModels"
xmlns:local="using:Win8Client">
<Application.Resources>
<vm:ViewModelLocator x:Key="Locator" />
</Application.Resources>
</Application>
At design time I get "Could not load file or assembly 'Microsoft.Threading.Tasks', version=1.0.12.0 ..." which is referring to my ViewModelLocator. This compiles and appears to run ok but I don't get any design time data. The design time data works fine in the WPF client.
Once running I see my first view but once this line gets called:
Slots = await _appointmentsDataProvider.GetAppointments(SelectedDate);
I get the following exception in the setter of my slots property which takes advantage of MVVM Lights Set method of ViewModelBase. The Slots property is NOT bound to any UI yet.
Exception:
"The application called an interface that was marshalled for a different thread. (Exception from HRESULT: 0x8001010E (RPC_E_WRONG_THREAD))"
Slots Property:
public List<Slot> Slots
{
get { return _slots; }
set
{
Set(SlotsPropertyName, ref _slots, value); // <-- Exception thrown here
}
}
Realised I haven't actually asked a question. Simply, I would like to know, what is the best approach for using MVVM Light with a Windows Store App?
Thanks in advance for any help or advice!
The first issue "Could not load file or assembly 'Microsoft.Threading.Tasks', version=1.0.12.0 ..." I haven't worked out yet but from time to time I do see the design data. Seems very temperamental...
The second issue - The reason this through me a bit was because is "just worked" in WPF and I assumed it would just work in a Windows Store App. Wrong. It looks like Windows Store Apps handle async/await threading differently - that's my guess.
Fix: Created an IDispatcherHelper interface in PCL with a single method declaration:
void RunOnUIThread(Action action);
Then created a single concrete DispatcherHelper class in each platform specific project (WPF/Windows 8.1) which implement IDispatcherHelper. Each implementation simply calls MVVM Lights:
DispatcherHelper.CheckBeginInvokeOnUI(action);
In App.xaml.cs in the WPF and Windows 8.1 I simply registered the concrete implementations with MVVM Lights SimpleIoc with the IDispatcherHelper as the handle. Within the view model I then use the platform specific implementations through the interface:
var slots = await _appointmentsDataProvider.GetAppointments(SelectedDate);
IDispatcherHelper dispatcherHelper = SimpleIoc.Default.GetInstance<IDispatcherHelper>();
dispatcherHelper.RunOnUIThread(() =>
{
Slots = slots;
});
Got to love abstraction!
I'm interested in calling a C# method from C++ code in Windows Phone 8. I have already learned how to pass a callback function to C++ code from C# via delegate declarations in my C++ code, but I am looking to see if I can do any of the following:
Call certain methods directly from the C++ code. This would involve somehow inspecting the C# object makeup from C++, and seems unlikely to me, but I thought I'd ask you all anyway
Trigger events in the C# code, which can then be handled by C# methods
Use a dispatcher to call C# callbacks in the Main UI thread so that the callbacks can modify UI elements
Use a dispatcher to trigger events in the C# code, (Essentially a merging of the above two points)
In short, I am looking for as many C++ -->C# communication tips as you guys can throw me, I want to learn it all. :)
By getting an object in C# code to implement a Windows RT interface, and passing down a reference to this object, it is possible to do all of the above with a bit of set-up (if I understand correctly - not sure about exactly what you want to do with your Dispatcher examples - you might want to wrap the Dispatcher on the C# side).
Create a Windows Runtime component library.
Define a public interface class in a C++/CX header for the C# to implement (C++ to call) (e.g. ICallback).
Define a public ref class in a C++/CX header for the C++ to implement (C# to call) (e.g. CppCxClass).
Add a method in CppCxClass that passes and stores an ICallback. (A C++ global variable is shown for consiseness, I recommend you review this to see if you can find a better place to store this in your code-base).
ICallback^ globalCallback;
...
void CppCxClass::SetCallback(ICallback ^callback)
{
globalCallback = callback;
}
Reference the WinRT library in your C# code.
C# code: create an instance of CppCxClass using var cppObject = new CppCxClass().
C# code: create a class which implements ICallback (e.g. CSharpCallbackObject).
C# code: pass an instance of CSharpCallbackObject down to C++. E.g. cppObject.SetCallback(new CSharpCallbackObject()).
You can now call C# with globalCallback->CallCsharp(L"Hello C#");. You should be able to extend either ICallback and/or CppCxObject to do the rest of your tasks.
After a lot of headaches trying to figure out the required code, I think it's worth posting the final version here
C++/CX
//.h
[Windows::Foundation::Metadata::WebHostHidden]
public interface class ICallback
{
public:
virtual void Exec( Platform::String ^Command, Platform::String ^Param);
};
//.cpp
ICallback ^CSCallback = nullptr;
void Direct3DInterop::SetCallback( ICallback ^Callback)
{
CSCallback = Callback;
}
//...
if (CSCallback != nullptr)
CSCallback->Exec( "Command", "Param" );
C#
public class CallbackImpl : ICallback
{
public void Exec(String Command, String Param)
{
//Execute some C# code, if you call UI stuff you will need to call this too
//Deployment.Current.Dispatcher.BeginInvoke(() => {
// //Lambda code
//}
}
}
//...
CallbackImpl CI = new CallbackImpl();
D3DComponent.SetCallback( CI);
I'm doing an Windows Phone app where I have a WebApi running in Azure.
I'm using the new "Portable Class Library" (http://msdn.microsoft.com/en-us/library/gg597391.aspx) for my "Models" project which is of cause shared between my WebApi project (this is a normale ASp.NET MVC 4 project) and my Windows Phone project.
This works great and the model (POCO) classes are serialized and deserialized just as I want.
Now I want to start storing some of my Models/POCO objects and would like to use EF Code-first for that, but that's kind of a problem as I can't add the EntityFramework assembly to my "Portable Class Library" project, and really I would not like to either as I only need a small part (the attributes) in my Models project.
So, any suggestions to how a approach this the best way?
UPDATE:
Well, it seems like I can actually add the EntityFramework assembly to the project, but that doesn't really help me, as the attributes I need to use lives in System.ComponentModel.DataAnnotations which can't be used on Windows Phone.
Any suggestions still?
Don't use attributes. Use fluent API instead and create separate assembly for persistence (EF) which will reference your model assembly. Persistence assembly will be use used by your WebAPI layer.
I use a modified approach than Mikkel Hempel's, without the need to use pre processing directives.
Create a standard .NET class library, call it Models
Create a partial class representing what you want to be shared
public partial class Person
{
public int Id { get; set; }
public string Name { get; set; }
}
For non-portable code (like DataAnnotations), create another partial class and use Metadata
[MetadataTypeAttribute(typeof(Person.Metadata))]
public partial class Person
{
internal sealed class Metadata
{
private Metadata() { } // Metadata classes shouldn't be instantiated
// Add metadata attributes to perform validation
[Required]
[StringLength(60)]
public string Name;
}
}
Create a Portable Class Library, and add the class from step 2 "As Link"
When I need my domain-project across multiple platforms, I usually:
Create the standard .NET-class library project for the domain code
For each platform I create a platform specific class library
For each platform specific class library I add the files from the standard .NET-class library as links (Add existing files -> As link) and hence they're updated automatically when you edit either the linked file or the original file.
When I add a new file to the .NET-class library, I add it as links to the platform specific class libraries.
Platform specific attributes (i.e. Table and ForeignKey which is a part of the DataAnnotations-assembly) can be opted out using the pre-processor tags. Lets say I have a .NET-class library with a class and a Silverlight-project with the linked file, then I can include the .NET-specific attributes by doing:
#if !SILVERLIGHT
[Table("MyEntityFrameworkTable")]
#endif
public class MyCrossPlatformClass
{
// Blah blah blah
}
and only include the DataAnnotations-assembly in the .NET-class library.
I know it's more work than using the Portable Class Library, but you can't opt out attributes in a PCL like in the example above, since you're only allowed to reference shared assemblies (which again DataAnnotations is not).