Basic Xamarin Android SDK Issue

Issue

I've never struggled with anything in programming as much as this Xamarin installation, unbelievably flakey. I've got my environment (VS 2015 Enterprise) to a point whereby I can spin up a new Blank App (Android) but the designer requires a newer version of the Android SDK (apparently):

I've only just installed the latest Android Studio, so I can confirm (in Xamarin settings) I'm pointing to the correct path for the SDK (in AppData/Local etc.)

On opening the SDK manager I can see the latest SDK tools is installed.

Please note: I've also tried running the SDK manager independently of VS (and as admin).

Never had this much trouble trying to get something installed and configured. Any help MASSIVELY appreciated.

Whoever helps me crack this gets a massive bounty.

EDIT:

Found this in the logs, fairly certain this is the issue:

Xamarin.VisualStudio.Android.MonoAndroidDesignerPane Error: 0 : [2016-09-22 16:36:54.2716] System.AggregateException: One or more errors occurred. ---> System.NullReferenceException: Object reference not set to an instance of an object. at System.Collections.Generic.Dictionary`2.Insert(TKey key, TValue value, Boolean add) at Xamarin.VisualStudio.Android.Designer.MonoAndroidDesignerDocumentCache.Push(String filePath, AndroidDesignerDocumentCacheItem value) in C:\data\lanes\3513\c4382f51\source\xamarinvs\src\Core\VisualStudio.Android\Designer\MonoAndroidDesignerDocumentCache.cs:line 25 at Xamarin.VisualStudio.Android.MonoAndroidDesignerPane.OpenViewCode() in C:\data\lanes\3513\c4382f51\source\xamarinvs\src\Core\VisualStudio.Android\Designer\MonoAndroidDesignerPane.cs:line 619 at Xamarin.VisualStudio.Android.MonoAndroidDesignerPane.b__66_0() in C:\data\lanes\3513\c4382f51\source\xamarinvs\src\Core\VisualStudio.Android\Designer\MonoAndroidDesignerPane.cs:line 612

EDIT

Bounty is for Jon when it allows me to award it. This issue has already been resolved.

Solution

Try to delete your obj/bin folders as it seems you might have an AndroidSdksCache holding the old version. Specifically look for a file here obj\Debug\sdks.cache.

The second note is that you have build-tools 23.0.0 installed. Please uninstall that version and any other old version and install 24.0.2.

It shows the current directory as being C:\sdk1\ when the referenced SDK version is different in your screenshot. You will need to update C:\sdk1\ to the latest Android SDK Tools.

Answered By - Jon Douglas