Here is the new & improved Rubberduck 2.x entry point class, based on MZ-Tools 8.0's Connect.VBA implementation of the IDTExtensibility2 COM interface, graciously shared to the Rubberduck team by Mr. MZ-Tools himself, Carlos Quintero.
The modifications made are not yet merged into the project's main repository at the time of this writing, but you can view it on commit 8ac768d9 in my own fork.
I've yet to shim the add-in to get it to be a good citizen and run in its own dedicated AppDomain (.net creates RCW's per-AppDomain, that's why it does matter), so there are still a number of issues beyond just the "entry point" to completely stabilize Rubberduck 2.x, but for now I'm interested in feedback specifically on the IDTExtensibility2 implementation - a useful add-in, I'm discovering, is much trickier to "do right" than what the "hello world" tutorials imply.
Also, since we're using ninject for dependency injection, I'm also interested in feedback on the composition root here, the handling of the _kernel instance and, given the various different ways an add-in can be loaded/unloaded, whether this (which seems to work fine) is done right.
Of course, any other feedback is welcome, too.
using Extensibility;
using Microsoft.Vbe.Interop;
using Ninject;
using Ninject.Extensions.Factory;
using Rubberduck.Root;
using Rubberduck.UI;
using System;
using System.ComponentModel;
using System.Globalization;
using System.IO;
using System.Reflection;
using System.Runtime.InteropServices;
using System.Windows.Forms;
using System.Windows.Threading;
using Ninject.Extensions.Interception;
using NLog;
using Rubberduck.Settings;
using Rubberduck.SettingsProvider;
namespace Rubberduck
{
/// <remarks>
/// Special thanks to Carlos Quintero (MZ-Tools) for providing the general structure here.
/// </remarks>
[ComVisible(true)]
[Guid(ClassId)]
[ProgId(ProgId)]
[EditorBrowsable(EditorBrowsableState.Never)]
// ReSharper disable once InconsistentNaming // note: underscore prefix hides class from COM API
public class _Extension : IDTExtensibility2
{
private const string ClassId = "8D052AD8-BBD2-4C59-8DEC-F697CA1F8A66";
private const string ProgId = "Rubberduck.Extension";
private VBE _ide;
private AddIn _addin;
private bool _isInitialized;
private bool _isBeginShutdownExecuted;
private IKernel _kernel;
private App _app;
private readonly Logger _logger = LogManager.GetCurrentClassLogger();
public void OnAddInsUpdate(ref Array custom) { }
// ReSharper disable InconsistentNaming
public void OnConnection(object Application, ext_ConnectMode ConnectMode, object AddInInst, ref Array custom)
{
try
{
_ide = (VBE)Application;
_addin = (AddIn)AddInInst;
_addin.Object = this;
switch (ConnectMode)
{
case ext_ConnectMode.ext_cm_Startup:
// normal execution path - don't initialize just yet, wait for OnStartupComplete to be called by the host.
break;
case ext_ConnectMode.ext_cm_AfterStartup:
InitializeAddIn();
break;
}
}
catch (Exception e)
{
Console.WriteLine(e);
}
}
Assembly LoadFromSameFolder(object sender, ResolveEventArgs args)
{
var folderPath = Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location);
var assemblyPath = Path.Combine(folderPath, new AssemblyName(args.Name).Name + ".dll");
if (!File.Exists(assemblyPath))
{
return null;
}
var assembly = Assembly.LoadFile(assemblyPath);
return assembly;
}
public void OnStartupComplete(ref Array custom)
{
InitializeAddIn();
}
public void OnBeginShutdown(ref Array custom)
{
_isBeginShutdownExecuted = true;
ShutdownAddIn();
}
// ReSharper disable InconsistentNaming
public void OnDisconnection(ext_DisconnectMode RemoveMode, ref Array custom)
{
switch (RemoveMode)
{
case ext_DisconnectMode.ext_dm_UserClosed:
ShutdownAddIn();
break;
case ext_DisconnectMode.ext_dm_HostShutdown:
if (_isBeginShutdownExecuted)
{
// this is the normal case: nothing to do here, we already ran ShutdownAddIn.
}
else
{
// some hosts do not call OnBeginShutdown: this mitigates it.
ShutdownAddIn();
}
break;
}
}
private void InitializeAddIn()
{
if (_isInitialized)
{
// The add-in is already initialized. See:
// The strange case of the add-in initialized twice
// http://msmvps.com/blogs/carlosq/archive/2013/02/14/the-strange-case-of-the-add-in-initialized-twice.aspx
return;
}
_kernel = new StandardKernel(new NinjectSettings { LoadExtensions = true }, new FuncModule(), new DynamicProxyModule());
try
{
var currentDomain = AppDomain.CurrentDomain;
currentDomain.AssemblyResolve += LoadFromSameFolder;
var config = new XmlPersistanceService<GeneralSettings>
{
FilePath = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData), "Rubberduck", "rubberduck.config")
};
var settings = config.Load(null);
if (settings != null)
{
try
{
var cultureInfo = CultureInfo.GetCultureInfo(settings.Language.Code);
Dispatcher.CurrentDispatcher.Thread.CurrentUICulture = cultureInfo;
}
catch (CultureNotFoundException) { }
}
_kernel.Load(new RubberduckModule(_ide, _addin));
_app = _kernel.Get<App>();
_app.Startup();
_isInitialized = true;
}
catch (Exception exception)
{
_logger.Fatal(exception);
System.Windows.Forms.MessageBox.Show(exception.ToString(), RubberduckUI.RubberduckLoadFailure, MessageBoxButtons.OK, MessageBoxIcon.Error);
}
}
private void ShutdownAddIn()
{
if (_app != null)
{
_app.Shutdown();
_app = null;
}
if (_kernel != null)
{
_kernel.Dispose();
_kernel = null;
}
Marshal.ReleaseComObject(_addin);
Marshal.ReleaseComObject(_ide);
_isInitialized = false;
}
}
}
