Xamarin Forms

Since .NET and Xamarin were open sourced, I’ve kept a casual watch on their repositories for interesting things.

Recently I noticed this pull request “Change appearance of NSTabView”. This immediately stood out since NSTabView is an AppKit (i.e. macOS) API as opposed to a UIKit (i.e iOS) API.

A quick read of the details and is indeed about some difference between NSTabView and UITabBar. The pull request is targeting the branch “macos” and it seems it’s been in development since at least August 17th.

TLDR: An error containing “–no-version-vectors” is probably fixed by updating your Android SDK Build Tools to at least 23.

I recently upgraded a project to the latest version of Xamarin Forms and got the following error: /Library/Frameworks/Mono.framework/External/xbuild/Xamarin/Android/Xamarin.Android.Common.targets: Error: Tool exited with code: 2. Output: ERROR: Unknown option '--no-version-vectors'

A quick $ grep -ri "no-version" . on the project revealed it was being used in a dependency brought in by the Forms update: ./packages/Xamarin.Android.Support.Vector.Drawable.23.3.0/build/Xamarin.Android.Support.Vector.Drawable.targets: $(AndroidResgenExtraArgs)--no-version-vectors

Long story short, this parameter is for the aapt tool in the Android SDK Build Tools from at least version 23. Updating through the Android SDK manager fixed it.