Visual Studio Add-in Library

using System;
using System.Collections.Generic;
using System.Reflection;
using System.Runtime.InteropServices;
using VisualStudio.AddInLibrary.Menus;
using EnvDTE;
using EnvDTE80;
using Extensibility;
using stdole;

namespace VisualStudio.AddInLibrary
{
  [ComVisible(true)]
  [ClassInterface(ClassInterfaceType.None)]
  public class CommandManager : IDispatch, IDTCommandTarget, IDTExtensibility2
  {
    /// <summary>
    /// The client assembly <---> the plugin
    /// </summary>
    protected Assembly PluginAssembly = null;


    /// <summary>
    /// Internal list containing our command class instances
    /// </summary>
    List<IMenuImplementation> MenuList= new List<IMenuImplementation>();


    public void AddCommand(IMenuImplementation menu)
    {
      MenuList.Add(menu);
    }

    /// <summary>
    /// Creates and install Menu /sub-menus
    /// </summary>
    public void InstallMenus()
    {
      foreach (IMenuImplementation imp in MenuList)
      {
        imp.Install();
      }  
    }

    /// <summary>
    /// Remove menus & submenus
    /// </summary>
    public void UnInstallMenus()
    {
      foreach (IMenuImplementation imp in MenuList)
      {
        imp.UnInstall();
      }
      MenuList.Clear();
    }

    /// <summary>
    /// User/Plugin Method called to create the menus and their commands
    /// </summary>
    protected virtual void CreateCommands()
    {
      throw new Exception("NOT SUPPORTED - CreateCommands must be implemented in derived class !");
    }   


    #region IDTCommandTarget Members

    public void Exec(string CmdName, vsCommandExecOption ExecuteOption, ref object VariantIn, ref object VariantOut, ref bool Handled)
    {
      bool ret = false;
      foreach (IMenuImplementation imp in MenuList)
      {
        if (imp.IsItMycommand(CmdName))
        {
          ret = imp.Exec(CmdName);
          if (ret) break;
        }
      }
      Handled =  ret;
    }

    public void QueryStatus(string CmdName, vsCommandStatusTextWanted NeededText, ref vsCommandStatus StatusOption, ref object CommandText)
    {
      StatusOption = (vsCommandStatus)vsCommandStatus.vsCommandStatusSupported | vsCommandStatus.vsCommandStatusEnabled;
      foreach (IMenuImplementation imp in MenuList)
      {
        // to whom this command belongs too ...
        if (imp.IsItMycommand(CmdName))
        {
          MenuState m = imp.GetState(CmdName, NeededText, ref CommandText);
          switch (m)
          {
            case MenuState.Enabled:
              StatusOption = (vsCommandStatus)vsCommandStatus.vsCommandStatusSupported | vsCommandStatus.vsCommandStatusEnabled;
              break;

            case MenuState.Disabled:
              StatusOption = vsCommandStatus.vsCommandStatusSupported;
              break;

            case MenuState.Hidden:
              StatusOption = vsCommandStatus.vsCommandStatusInvisible;
              break;

            case MenuState.Unknown:
            case MenuState.Unapplicable:
              StatusOption = vsCommandStatus.vsCommandStatusSupported;
              break;
          }
          break;
        }
      }            
    }

    #endregion


    #region IDTExtensibility2 Members

    /// <summary>Implements the OnDisconnection method of the IDTExtensibility2 interface. Receives notification that the Add-in is being unloaded.</summary>
    /// <param term='disconnectMode'>Describes how the Add-in is being unloaded.</param>
    /// <param term='custom'>Array of parameters that are host application specific.</param>
    /// <seealso class='IDTExtensibility2' />
    public virtual void OnDisconnection(ext_DisconnectMode disconnectMode, ref Array custom)
    {
      UnInstallMenus();
    }

    /// <summary>Implements the OnAddInsUpdate method of the IDTExtensibility2 interface. Receives notification when the collection of Add-ins has changed.</summary>
    /// <param term='custom'>Array of parameters that are host application specific.</param>
    /// <seealso class='IDTExtensibility2' />		
    public virtual void OnAddInsUpdate(ref Array custom)
    {
    }

    /// <summary>Implements the OnStartupComplete method of the IDTExtensibility2 interface. Receives notification that the host application has completed loading.</summary>
    /// <param term='custom'>Array of parameters that are host application specific.</param>
    /// <seealso class='IDTExtensibility2' />
    public virtual void OnStartupComplete(ref Array custom)
    {
      InstallMenus();

    }

    /// <summary>Implements the OnBeginShutdown method of the IDTExtensibility2 interface. Receives notification that the host application is being unloaded.</summary>
    /// <param term='custom'>Array of parameters that are host application specific.</param>
    /// <seealso class='IDTExtensibility2' />
    public virtual void OnBeginShutdown(ref Array custom)
    {
    }

    /// <summary>Implements the OnConnection method of the IDTExtensibility2 interface. Receives notification that the Add-in is being loaded.</summary>
    /// <param term='application'>Root object of the host application.</param>
    /// <param term='connectMode'>Describes how the Add-in is being loaded.</param>
    /// <param term='addInInst'>Object representing this Add-in.</param>
    /// <seealso class='IDTExtensibility2' />
    public void OnConnection(object application, ext_ConnectMode connectMode, object addInInst, ref Array custom)
    {
      try
      {
        _applicationObject = (DTE2)application;
        _addInInstance = (AddIn)addInInst;

        if (connectMode == ext_ConnectMode.ext_cm_Startup)
        {
          // call derived class methods
          CreateCommands();          
        }

        if (connectMode == ext_ConnectMode.ext_cm_AfterStartup)
          InstallMenus();

      }
      catch (System.Exception e)
      {
        System.Windows.Forms.MessageBox.Show(e.ToString());
      }

    }
    #endregion


    protected DTE2 _applicationObject = null;
    protected AddIn _addInInstance = null;

   

  }
}