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sqlitemonoxamarinmvvmcrossportable-class-library

Mono.Data.Sqlite.SqliteConnection requiring a version of 'System' that doesn't make sense

We're having issues with our Sqlite PCL Project.

The issues

1) Anywhere that references Mono.Data.Sqlite.SqliteConnection shows the following error.

Module 'System, Version 4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' should be referenced.

2) Anything trying to use File.Exists is showing a compiler error

Cannot resolve symbol 'File'

The particulars

We're using .NET Portable Subset 158

  • C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETPortable\v4.0\Profile\Profile158\

We've included

  • Mono.Data.Sqlite
    • C:\Program Files (x86)\Mono-3.2.3\lib\mono\4.5\Mono.Data.Sqlite.dll
  • System.Data
    • C:\Program Files (x86)\Mono-3.2.3\lib\mono\4.5\System.Data.dll

I have no idea where to go from here.

Here's a class file containing the issues with SqliteConnection

using System;
using Mono.Data.Sqlite;

namespace OurApplication.AppCore.Data.Sqlite
{
    public class DbConnectionProvider : IDbConnectionProvider
    {
        private readonly string _connectionString;

        public DbConnectionProvider(string sqliteDatabasePath, string databaseName)
        {
            // the sqliteDatabasePath is hard coded in 'Data.Sqlite.DbProvider'
            //     _sqliteDatabasePath = "{0}.sqlite3";
            _connectionString = string.Format("Data Source=" + sqliteDatabasePath, databaseName);
        }

        public SqliteConnection GetOpenConnection()
        {
            var connection = new SqliteConnection(_connectionString);
            if (connection == null) throw new Exception("Could not create a database connection.");

            connection.Open();

            return connection;
        }
    }
}

Gist with more code examples

If this approach isn't feasible, I'm open to other alternatives. I'm looking into Sqlite.Net but the API doesn't really do what I want with regards to a custom DbReader and such.

I'm also interested in Stuart Lodge's MvvmCross Sqlite stuff, but really have no idea how to integrate the platform specific goodness. Honestly, I can't even figure out how to Execute Parameterized Queries.

I think my preference would be to use MvvmCross-SQLite if I can just get it figured out.

For references, this is how our Solution is structured.

  • OurApplication.App.Droid
  • OurApplication.AppCore
  • OurApplication.AppCore.Data.Sqlite (This is the project I'm working in.)
  • OurApplication.AppCore.Data.SqlServer
Solution

  • For non-portable APIs MvvmCross generally provides interfaces within PCLs with platform specific implementations on each platform.

    The pattern used is called "plugins" - but really these are just a simple layer on top of an IoC container. You can see more about this on:

    For File.Exists, MvvmCross provides an IMvxFileStore api - see https://github.com/MvvmCross/MvvmCross/blob/v3/Plugins/Cirrious/File/Cirrious.MvvmCross.Plugins.File/IMvxFileStore.cs

    For SQLite MvvmCross has wrapped the SQLite-net library.

    • The original attempt to do this is in https://github.com/MvvmCross/MvvmCross/tree/v3/Plugins/Cirrious/Sqlite and is based off an early 2012 version of SQLite-net. A video intro to this is available in N-10 in http://mvvmcross.wordpress.com. This project has now been marked as obsolete simply because I don't plan to do any updates to it.

    • The newer attempt at portable SQLite-net has been put in its own repo to allow more people to contribute to it without confusing the main MvvmCross repo. It is in https://github.com/MvvmCross/MvvmCross-Sqlite - it is based off the latest SQLite-net (late 2013) which was split into interface and non-interface parts by @jarroda. The same N-10 video intro from http://mvvmcross.wordpress.com should work with this project too - just with a different namespace.

      This source is currently live and builds fine here in my stable WinRT/WP7/Xamarin VS2012 environment. There will be changes in the coming weeks to address changes forced on MvvmCross by the latest Xamarin and Microsoft PCL changes. I'm afraid no-one can help with "spewing out errors" - that's not a techie term anyone can really help with.

    There is at least one other PCL adaption of SQLite-net I've seen recently - but I can't find a link to that at present.