Use SQLiteNetextensions with Xamarin for Android-App

问题

I've read some threads about SQLite for Xamarin but I'm still not able to set up SQLiteNetExtensions in a proper way. I'm currently developing an android app with Target Framework Android 7.1(API Level 25 - Nougat).

Can anybody tell me what I'm doing wrong?

I installed nuget packages:

Install-Package SQLiteNetExtensions -Version 2.0.0-alpha2 -Pre

Install-Package SQLite.Net-PCL -Version 3.1.1

According to: https://bitbucket.org/twincoders/sqlite-net-extensions

Then I set up my code.

using SQLite.Net.Attributes;
using SQLiteNetExtensions.Attributes;
using System;

namespace AppName.Resources.Model
{
  public class Entry
  {
    [PrimaryKey, AutoIncrement]
    public int Id { get; set; }
    [ForeignKey(typeof(Stock))]
    public int StockId { get; set; }
    public DateTime Date { get; set; }
    public double Amount { get; set; }
  }
}

using SQLite.Net.Attributes;
using SQLiteNetExtensions.Attributes;
using System;
using System.Collections.Generic;

namespace AppName.Resources.Model
{
  public class Stock
  {
    [PrimaryKey, AutoIncrement]
    public int Id { get; set; }
    public string Name { get; set; }
    public DateTime LastUpdated { get; set; }
    [OneToMany(CascadeOperations = CascadeOperation.All)]
    public List<Entry> Entrys { get; set; }
  }
}

using Android.Util;
using AppName.Resources.Model;
using SQLite.Net;
using SQLite.Net.Platform.XamarinAndroid;
using SQLiteNetExtensions.Extensions;
using System.Collections.Generic;
using System.IO;

namespace AppName.Resources.DataHelper
{
  public class DataBase
  {
    string folder = System.Environment.GetFolderPath(System.Environment.SpecialFolder.Personal);
    public bool CreateDataBase()
    {
      try
      {
        using (var stocksDBConnection = new SQLiteConnection(new SQLitePlatformAndroid(), Path.Combine(folder, "Stock.db")))
        {
          stocksDBConnection.CreateTable<Entry>();
          stocksDBConnection.CreateTable<Stock>();    
          return true;
        }
      }
      catch (SQLiteException ex)
      {
        Log.Info("SQLiteEx", ex.Message);
        return false;
      }
    }

    public bool InsertIntoTableStock(object stock)
    {
      try
      {
        using (var stocksDBConnection = new SQLiteConnection(new SQLitePlatformAndroid(), Path.Combine(folder, "Stock.db")))
        {
          stocksDBConnection.InsertWithChildren(stock);
          return true;
        }
      }
      catch (SQLiteException ex)
      {
        Log.Info("SQLiteEx", ex.Message);
        return false;
      }
    }
    ...

These References were added by nuget:

SQLite-net

SQLite.Net

SQLite.Net.Platform.XamarinAndroid

SQLiteNetExtensions

SQLitePCLRaw.Batteries_green

SQLitePCLRaw.Core

SQLitePCLRaw.lib.e_sqlite3

SQLitePCLRaw.provider.e_sqlite3
Occuring error:

'SQLiteConnection' does not contain a definition for 'InsertWithChildren' and the best extension method overload 'WriteOperations.InsertWithChildren(SQLiteConnection, object, bool)' requires a receiver of type 'SQLiteConnection'

'SQLiteConnection' does not contain a definition for 'GetAllWithChildren' and the best extension method overload 'ReadOperations.GetAllWithChildren(SQLiteConnection, Expression>, bool)' requires a receiver of type 'SQLiteConnection'

Well that's how far I get. Anybody out there who knows what to do? Maybe remove conflicting references?

回答1:

Ok I'm sure that its just a version problem because I just tried your code and it works fine for me. Try installing SQliteNetExtensions v 1.3.0 package from the NuGet package manager window in Visual Studio and nothing else. It will install all its dependencies.

Here is what I did - Try to do the same and see if this helps :

I Created a new Android Single View App Project in Visual Studio (I'm using community 2017 - but it should not matter ) and created
the Stock , Entry and Database Classes and pasted your given
code respectively.
I installed only the SQliteNetExtensions v 1.3.0 package from the NuGet Package Manager It installed the following dependencies along with it, I didn't installed these myself.
SQLite.Net-PCL v3.0.5
NewtonSoft.Json v6.0.8

Here is what I got after installing just SQliteNetExtensions v 1.3.0 package.

As you can see its showing an update for SQLite.Net-PCL v3.0.5 to v3.1.1 I tired also with the updated one and it still works fine , so its up to you to update or not.

Here a bit proof that its working fine. I also compiled and run the app on emulator and it works all fine.

回答2:

Ok after a bit of searching , I came to know that the creator of this extension used a pattern called MvvmCross while developing it. So unless you are using that pattern model you will get this error.

For non-MvvmCross users they have to rebuild the source files and reference it in their project and not use the pre-compiled one, the one you are using.

Go to the fourth post on the following link https://forums.xamarin.com/discussion/20117/sqlite-net-extensions-and-sqliteconnection here he tells how to rebuild from source in his post in a very brief manner.

Hope you will understand it but if not wait till I install Visual Studio and Xamarin and try it out myself so I can give you accurate steps. It will take a while so till then , Kudos!

Here is the link to source files https://bitbucket.org/twincoders/sqlite-net-extensions/downloads/ Click on download repository

回答3:

After some research I found out that:

Install-Package SQLiteNetExtensions -Version 2.0.0-alpha2 -Pre

depends on

Install-Package sqlite-net-pcl

instead of

Install-Package SQLite.Net-PCL -Version 3.1.1

But after removing all references, cleaning the solution and reinstalling the two needed packages there is no SQLite.net available anymore. When trying to use SQLite instead:

'SQLiteConnection' does not contain a definition for 'InsertWithChildren' and the best extension method overload 'WriteOperations.InsertWithChildren(SQLiteConnection, object, bool)' requires a receiver of type 'SQLiteConnection'

I'm curious if it's even possible to develop Android-Apps with VS seamlessly. Since everything takes years to set up.

EDIT:

Well, after some days of pain in the a** the solution was to use the even newer pre release (alpha3) which wasn't even referenced to on the official pages. Currently I'm satisfied. :)

Install-Package SQLiteNetExtensions-netstandard -Version 2.0.0-alpha3 -Pre

Hope anybody may need this.

回答4:

I just solved this after doing a whole load of updates. Hit the same issues.

Uninstall ALL SQLite plugins. See attached pic/link below.
Reinstall SQLiteNetExtensions and this installs all dependencies too, actually all files in that list except SQLite.Net-PCL.
SQLiteNetExtensions installs SQLite-net-pcl but you need the other one too so, install SQLite.Net-PCL as well.
Restart Visual Studio as it doesn't always pickup all newly installed packages, the reopen your solution.

That worked for me so hopefully it'll help someone else here too.

来源：https://stackoverflow.com/questions/44617321/use-sqlitenetextensions-with-xamarin-for-android-app

标签

android

Xamarin

sqlite-net-extensions