Set Image.Source to file in external storage in Xamarin.Forms

Question

I have a picture of item in external storage (that was saved by intent in my app). I want to display this picture in Image view in my shared project.

Answer 1

Your Xamarin Forms PCL don't know what its a URI from Android beacuse its platform specific, so:

ImageSource.FromFile(path);

won't work.

In that case you are handling platform specific features, that is loading an image from Android. I suggest this approach:

Create an interface on Xamarin Forms PCL like:

public interface IPhoto
{
    Task<Stream> GetPhoto ();
}

Then in Android you implement that interface and register the implementation in DependencyService:

[assembly: Xamarin.Forms.Dependency(typeof(PhotoImplementation))]
    namespace xpto
    {
        public class PhotoImplementation : Java.Lang.Object, IPhoto
        {
            public async Task<Stream> GetPhoto()
            {
                // Open the photo and put it in a Stream to return       
                var memoryStream = new MemoryStream();

                using (var source = System.IO.File.OpenRead(path))
                {
                    await source.CopyToAsync(memoryStream);
                }

                return memoryStream;
            }
        }
    }

In the Xamarin Forms PCL code get the image:

var image = ImageSource.FromStream ( () => await DependencyService.Get<IPhoto>().GetPhoto());

For more detail you can consult this.

NOTE1: This will work on iOS if you implement the interface IPhoto too.

NOTE2: There exist a helpful library for this kind of features from Xamarin-Forms-Labs called Camera.

---

UPDATE (Shared Project solution)

As requested in the comments, to use this in a Shared Project instead of PCL we could do this.

1 - Place the IPhotoInterface in the Shared Project.

2 - Implement the interface in Android/iOS project:

public class PhotoImplementation : IPhoto
{
    public async Task<Stream> GetPhoto()
    {
        // Open the photo and put it in a Stream to return. 
    }
}

3 - Use it in the Shared Project:

IPhoto iPhotoImplementation;

#if __ANDROID__
iPhotoImplementation = new shared_native.Droid.GetPicture();

#elif __IOS__
iPhotoImplementation = new shared_native.iOS.GetPicture();

#endif

var image = ImageSource.FromStream ( () => await iPhotoImplementation.GetPhoto());

NOTE: shared_native is the namespace of my solution and Droid/iOS are the projects for Android and iOS.