Settings in MvvmCross Core assembly?

Question

In porting my WPF MVVM app to MvvmCross, what would be the recommended approach for persistent user settings in the Core assembly? Currently I'm using Properties.Settings for this task. Ideally, I'd like a solution that can play nicely with ClickOnce upgrades on Windows.

Thanks!

Answer 1

If you only want to support WPF, then you could continue using properties.settings.

If you want to support settings using native techniques on other platforms as well, then you could create an interface/abstraction for your settings and then use dependency injection to inject an appropriate settings implementation on each platform. You could do this in a plugin if you wanted to - but for getting started it's easiest to start by injecting this in your UI projects in Setup.cs (for how to build a plugin, see https://speakerdeck.com/cirrious/plugins-in-mvvmcross)

What I would probably do... is to use a portable settings implementation - either using a simple JSON file or using a small SQLite database (accessed via SQLite-net). This would enable you to reuse exactly the same code on all platforms. I don't know how this would work with ClickOnce (I don't know much about ClickOnce) but I'm assuming ClickOnce would preserve these data files during upgrades.

For portably saving a JSON file, see https://github.com/slodge/MvvmCross-Tutorials/blob/master/Sample%20-%20CirriousConference/Cirrious.Conference.Core/Models/FavoritesSaver.cs

For using SQLite-net, see https://speakerdeck.com/cirrious/using-sqlite-dot-net-in-mvvmcross - but be aware that the nuget packages for SQLite-net still suffer from the open issue on x64/x86/ARM differences - see How to distribute processor-specific WindowsStore assemblies with nuget :/