l am getting the error in the title and after some research l feel it has something to do with my redirctURI. Can some please help as l have been trying to authenticate using google for 2 days now.
RedirectUrl can be anything you as long as it is a valid URL or respect the following scheme (protocol:/somedata).
Normally, if we want to launch our app, RedirectUrl should start with package name(for example, if our package name is com.woodenmoose.xamarin.googleauth, the RedirectUrl is com.woodenmoose.xamarin.googleauth:/oauth2redirect) and the web browser tries to navigate to it, you can refer to this step by step link.http://timothelariviere.com/2017/09/01/authenticate-users-through-google-with-xamarin-auth/.
Answers
RedirectUrl can be anything you as long as it is a valid URL or respect the following scheme (protocol:/somedata).
Normally, if we want to launch our app, RedirectUrl should start with package name(for example, if our package name is com.woodenmoose.xamarin.googleauth, the RedirectUrl is com.woodenmoose.xamarin.googleauth:/oauth2redirect) and the web browser tries to navigate to it, you can refer to this step by step link.http://timothelariviere.com/2017/09/01/authenticate-users-through-google-with-xamarin-auth/.
@LeonLu l have the above but l am still getting system.urinullexception
Please provide complete error message. I think this issue is not related to the RedirectUrl, You can download this demo:https://developer.xamarin.com/samples/xamarin-forms/WebServices/OAuthNativeFlow/ , then create project for this demo in google console. Then just replace the
AndroidClientId
andAndroidRedirectUrl
in this demo, If you can running normally.Are there any updates for this issue? If the reply is helpful, please try to mark it as an answer, it will help others who have similar issue.
l have still not implemented this feature. Kindly direct me to a step by step tutorial if any exist
You can refer to this video about the whole steps.

Or you can refer to this offical artcle, it is clear.
https://docs.microsoft.com/en-us/xamarin/xamarin-forms/data-cloud/authentication/oauth
ok. l will revert shortly.
Ok, waitting for your update.
@Austy
Are there any updates for this issue? If the reply is helpful, please try to mark it as an answer, it will help others who have similar issue.