MAUI iOS EntityFramework Core - database is not created in Release iOS build

Question

The app I'm working on successfully creates am SQLite DB on Android or on an iOS Simulator and populates initial data, but Release iOS build on a real device just doesn't have any data.

I'm using Entity Framework Core Initially I was using SQLite Nuget packages. After switching to EF I cleaned things up - removed all related packages and added only those that EF pulled along with their Nuget.

I've created a context class

internal class MyDbContext : DbContext
{
    public MyDbContext() 
    {
        SQLitePCL.Batteries_V2.Init();

        this.Database.EnsureCreated();
    }

    public DbSet<Entity1> Entities1 { get; set; }
    public DbSet<Entity2> Entities2 { get; set; }
    public DbSet<Entity3> Entities3 { get; set; }

    protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
    {
        string dbPath = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData), "MyDatabase.db3");

        optionsBuilder
            .UseSqlite($"Filename={dbPath}");
    }
}

Made a base controller class

internal abstract class ControllerBase<T> where T : IDBItem, new()
{
    protected IMapper _mapper;

    /// <summary>
    /// Use only in case of unavoidable execution of raw sql
    /// </summary>
    protected MyDbContext GetContext() => new MyDbContext();

    public ControllerBase() 
    {
        var config = new MapperConfiguration(cfg => {
            cfg.AddProfile<DefaultMappingProfile>();
        });
        _mapper = config.CreateMapper();
    }
}

DB items look like this:

[PrimaryKey("Id")]
public class Entity1: IDBItem
{   
    public int Id { get; set; }

    public string Name { get; set; }

    public float SomeField { get; set; }
}

So whenever context get acquired from inheriting classes - there's a check that database is created. On Android this works. on iOS in Release mode I'm not seeing any databae entries. I do see some entries on Simulator though. That confuses me even more. Can any1 suggest a solution please?

I've tried to clean up Nuget packages as initially I was using SQLite PCL one. Removing all SQLite and installing only EF Core and those that it pulled didn't solve the issue.

Answer 1

After a lot of digging I found out that the error was caused by "Attempting to JIT compile method InitializeComponent while running in aot-only mode" It happened only in release mode on the device. The issue was caused by absence if tag <UseInterpreter>true</UseInterpreter> inside of the project file. Eventually it looked like this:

<PropertyGroup Condition="'$(Configuration)|$(TargetFramework)|$(Platform)'=='Release|net7.0-ios|AnyCPU'">
  [other option shere]
  <MtouchLink>SdkOnly</MtouchLink>
  <MtouchUseLlvm>False</MtouchUseLlvm>
  <UseInterpreter>true</UseInterpreter>
</PropertyGroup>

Link to the original issue: https://github.com/xamarin/xamarin-macios/issues/17194