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Hello,
can you tell me what error you get?

The RecognitionFragment fragment only performs image recognition but does not render anything, to do this you need an ARView that renders the camera and the digital elements.

From the github repository I see that the ARinterface activity adds the fragment RecognitionFragment but there isn't any ARView to render the camera. At this link there is a guide with the classes to add to create an ARView.

https://developer.pikkart.com/servizi/Menu/dinamica.aspx?idSezione=617&idArea=619&idCat=628&ID=1975&TipoElemento=page

However let me know with what error the app crashes.

Thank you.

Hi,
I looked at the repository and the problem here is that the activity is never launched and is not created before starting the recognition.

The change I would make is to instead of calling a method of the activity directly through a dependency service, use the dependency service to do the LaunchActivity causing the execution of the lifecycle of an Activity.

In the ShaPlay3 forms project i created an interface called ILaunchActivity which has the method LaunchActivityInAndroid:


public interface ILaunchActivity
{
void LaunchActivityInAndroid();
}


in the SplashScreen.xaml.cs class instead of replacing the MainPage with ARScreen I managed to call the LaunchActivityInAndroid method through a dependency service


private void StartButton_OnClicked(object sender, EventArgs e)
{
//Application.Current.MainPage = new NavigationPage(new ARScreen());

ARengine = DependencyService.Get();
ARengine.LaunchActivityInAndroid();
}


in the ShaPlay3.Android project I added a LaunchActivity class as a depencency service which extends the ILaunchActivity interface and which implements the LaunchActivityInAndroid method
in this method I launch the ARInterface activity.


[assembly: Xamarin.Forms.Dependency(typeof(LaunchActivity))]
namespace ShaPlay3.Droid
{
public class LaunchActivity : ILaunchActivity
{
public LaunchActivity()
{
}

public void LaunchActivityInAndroid()
{
var intent = new Intent(Forms.Context, typeof(ARinterface));
Forms.Context.StartActivity(intent);
}
}
}


However, the ARInterface activity has some differences.
first it needs to extend Activity instead of FormsAppCompatActivity, and then he has to override the OnCreate (Bundle bundle) method, inside the method he has to set the layout of the activity and then call the startAR method.


protected override void OnCreate(Bundle savedInstanceState)
{
base.OnCreate(savedInstanceState);

SetContentView(Resource.Layout.Main);

startAR();
}



Best reguards,

Hi,
you can now implement the renderer as described in the tutorial.

You cannot have an instance of the ARInterface because it is an activity and you cannot have multiple activities active at the same time.
That's why I thought about how to call certain functions from the ARScreen class of the Xamarin.Forms project.

The ARScreen class no longer calls the LaunchARActivityInAndroid function but defines an EventHandler that will be passed to the custom renderer.


[assembly: Xamarin.Forms.Dependency(typeof(ShaPlay3.IARinterface))]
namespace ShaPlay3.Views
{
[XamlCompilation(XamlCompilationOptions.Skip)] // Should be Skip?? Alt: Compile
public partial class ARScreen : ContentPage // This is where we should see the Pikkart AR activate
{

ILaunchARActivity ARengine;
public ARScreen()
{
InitializeComponent();
//ARengine = DependencyService.Get();
//ARengine.LaunchARActivityInAndroid();

testMarkerID();
}

private async void testMarkerID()
{
await Task.Delay(2000);

GetMarkerId();
}

public event EventHandler MarkerIdEvent;
public void GetMarkerId()
{
MarkerIdEvent?.Invoke(this, EventArgs.Empty);
}

private string _markerID;
public string MarkerID
{
set => _markerID = value;
}
}
}


The LaunchARActivity class is changed to an ARScreen custom renderer, OnElementChanged is overridden, and the ElementChangedEventArgs .NewElement parameter is cast to an ARScreen. This passes as the MarkerIdEvent event a method that will be defined.

This method now calls a static function of the ARinterface activity which returns a static variable containing the marker id


[assembly: ExportRenderer(typeof(ARScreen), typeof(LaunchARActivity))]
namespace ShaPlay3.Droid
{
public class LaunchARActivity : PageRenderer
{
private ARScreen _arScreen;

public LaunchARActivity(Context context) : base(context)
{

}

protected override void OnElementChanged(ElementChangedEventArgs e)
{
base.OnElementChanged(e);

if (e.NewElement != null)
{
_arScreen = (ARScreen)e.NewElement;

((ARScreen)e.NewElement).MarkerIdEvent += GetMarkerID;
}
var intent = new Intent(Forms.Context, typeof(ARinterface));
Forms.Context.StartActivity(intent);
}
private void GetMarkerID(object sender, EventArgs e)
{
string markerID = ARinterface.GetMarkerID();
_arScreen.MarkerID = markerID;
}
}
}


in the activity ARinterface create a copy of GetMarkerID but static so that it can be called from the custom renderer.


static string staticCurrentMarkerID = "";
public static string GetMarkerID()
{
return staticCurrentMarkerID;
}


Hi,
we are glad our answers are helping you.

1 - The class that manages the rendering of 3D models and videos on the marker is the ARRenderer. The ARRenderer inside it initializes a mesh using the json of the 3D model and an image for the texture, then draws it in the onDrawFrame method. So you can add the logic with which to decide what to show.
Find the explanation and the classes I told you about at this address:
https://developer.pikkart.com/servizi/Menu/dinamica.aspx?idSezione=617&idArea=619&idCat=628&ID=1975&TipoElemento=page

2 - You can prevent the activity from reloading by putting android:configChanges="orientation|screenSize" in the tag.

3 - The effect you see is a choice of user experience that we have decided to adopt so that the user always has the impression that augmented reality is working. So no, it's not removable.

4 - The "Powered by PIKKART" logo is shown only in apps that use a trial license, once the license has been purchased and replaced, the logo no longer appears.

Best reguards,