如何使用Xamarin.Forms的媒体插件在共享代码中实现iOS覆盖？

Question

I am trying to implement the overlay option for the media plugin in Xamarin, found here: https://github.com/jamesmontemagno/MediaPlugin

I understand how to use the feature in the iOS code, but am having trouble implementing it in the shared code.

Would really appreciate it if anyone knows what is wrong with my code, or if there is a working example of using the overlay feature in shared code.

I have setup an interface to handle the overlay for the iOS code, and have passed the function via a dependency service. It seems that the code block inside of func is skipping over when I set breakpoints and step into the function. The camera works but the overlay does not appear when using the camera.

IPhotoOverlay:

namespace Camera
{
public interface IPhotoOverlay 
{
   object GetImageOverlay();

    }
}

AppDelegate:

public override bool FinishedLaunching(UIApplication app, NSDictionary options)
    {
        global::Xamarin.Forms.Forms.Init();
        LoadApplication(new App());

        Xamarin.Forms.DependencyService.Register<IPhotoOverlay, PhotoOverlay_iOS>();

        return base.FinishedLaunching(app, options);
    }

PhotoOverlay_iOS:

[assembly: Xamarin.Forms.Dependency (typeof (PhotoOverlay_iOS))]
namespace Camera.iOS
{
public class PhotoOverlay_iOS: IPhotoOverlay
{

    public PhotoOverlay_iOS ()
    {
    }

    public object GetImageOverlay()
    {

        Func<object> func = () =>
        {
            var imageView = new UIImageView(UIImage.FromBundle("face-template.png"));
            imageView.ContentMode = UIViewContentMode.ScaleAspectFit;

            var screen = UIScreen.MainScreen.Bounds;
            imageView.Frame = screen;

            return imageView;
        };

        //Func<object> func = CreateOverlay;

        return func;
    }        

}
}

Shared Code:

var photo = await Plugin.Media.CrossMedia.Current.TakePhotoAsync(new Plugin.Media.Abstractions.StoreCameraMediaOptions()
            {
                OverlayViewProvider = DependencyService.Get<IPhotoOverlay>().GetImageOverlay,
                DefaultCamera = Plugin.Media.Abstractions.CameraDevice.Front
            });

Answer 1

Solution:

You can refer the following code .

in Forms

async void OpenCameraAsync()
{         
  Func<object> func = () =>
  {
    var obj = DependencyService.Get<IPhotoOverlay>().GetImageOverlay();       
    return obj;
  };

  var photo = await CrossMedia.Current.TakePhotoAsync(new Plugin.Media.Abstractions.StoreCameraMediaOptions()
  {
     OverlayViewProvider =func,
     DefaultCamera = Plugin.Media.Abstractions.CameraDevice.Front,
  });
}

in iOS project

public object GetImageOverlay()
{ 
  var imageView = new UIImageView(UIImage.FromBundle("yourimagename.png"));
  imageView.ContentMode = UIViewContentMode.ScaleAspectFit;

  var screen = UIScreen.MainScreen.Bounds;
  imageView.Frame = screen;

  return imageView;               
}