Xamarin ios - referenceUrl from UIImagePickerController always null - ios

Question

I'm selecting an image form the gallery using the UIImagePickerController. After selecting an image, I would like to update the real image file path on a text field.
Can I get the file path from the referenceUrl? The referenceUrl in my case always returns null.
protected void Handle_FinishedPickingMedia (object sender, UIImagePickerMediaPickedEventArgs e)
{
try{
//determine what was selected, video or image
bool isImage = false;
switch(e.Info [UIImagePickerController.MediaType].ToString()) {
case "public.image":
Console.WriteLine("Image selected");
isImage = true;
break;
}
// get common info (shared between images and video)
NSUrl referenceURL = e.Info[new NSString("UIImagePickerControllerReferenceUrl")] as NSUrl;
if (referenceURL != null)
Console.WriteLine("Url:"+referenceURL.ToString ());
// if it was an image, get the other image info
if(isImage) {
// get the original image
UIImage originalImage = e.Info[UIImagePickerController.OriginalImage] as UIImage;
if(originalImage != null) {
// do something with the image
new Thread(new System.Threading.ThreadStart(() => {
Thread.Sleep(350);
BeginInvokeOnMainThread (() => {
var tag = ((UIButton)sender).Tag;
//UIButton senderButton = (UIButton)sender;
switch(tag)
{
case 0:
// do something here
break;
case 1:
// do something here
break;
});
})).Start();
}
}
// dismiss the picker
imagePicker.DismissModalViewController (true);
}catch(Exception ex)
{
ShowAlert ("Failed !", "Unable to select image", "");
Console.WriteLine(ex.Message + ex.StackTrace);
}
}

Answer 1

For anyone else facing this issue, the solution was a simple typo.I printed out the details of the NSDictionary and noticed that the "Url" part of the
UIImagePickerControllerReferenceUrl was all caps. This is what worked for me.
Change this line:
NSUrl referenceURL = e.Info[new NSString("UIImagePickerControllerReferenceUrl")] as NSUrl;
To this :
NSUrl referenceURL = e.Info[new NSString("UIImagePickerControllerReferenceURL")] as NSUrl;
To get the filename of the selected image, I added the AssestsLibrary and used that to extract the necessary metadata.
Here's my full implementation:
protected void Handle_FinishedPickingMedia (object sender, UIImagePickerMediaPickedEventArgs e)
{
try{
//determine what was selected, video or image
bool isImage = false;
switch(e.Info [UIImagePickerController.MediaType].ToString()) {
case "public.image":
Console.WriteLine("Image selected");
isImage = true;
break;
}
// get common info (shared between images and video)
NSUrl referenceURL = e.Info[new NSString("UIImagePickerControllerReferenceURL")] as NSUrl;
if (referenceURL != null)
Console.WriteLine("Url:"+referenceURL.ToString ());
ALAssetsLibrary assetsLibrary = new ALAssetsLibrary();
assetsLibrary.AssetForUrl(referenceURL,delegate (ALAsset asset){
ALAssetRepresentation representation = asset.DefaultRepresentation;
if (representation == null)
{
return;
}else{
string fileName = representation.Filename;
Console.WriteLine("Image Filename :" + fileName);
}
},delegate(NSError error) {
Console.WriteLine ("User denied access to photo Library... {0}", error);
});
// if it was an image, get the other image info
if(isImage) {
// get the original image
UIImage originalImage = e.Info[UIImagePickerController.OriginalImage] as UIImage;
if(originalImage != null) {
// do something with the image
new Thread(new System.Threading.ThreadStart(() => {
Thread.Sleep(350);
BeginInvokeOnMainThread (() => {
var tag = ((UIButton)sender).Tag;
//UIButton senderButton = (UIButton)sender;
switch(tag)
{
case 0:
// do something here
break;
case 1:
// do something here
break;
});
})).Start();
}
}
// dismiss the picker
imagePicker.DismissModalViewController (true);
}catch(Exception ex)
{
ShowAlert ("Failed !", "Unable to select image", "");
Console.WriteLine(ex.Message + ex.StackTrace);
}
}