How to update the contents of a DynamicItemStart button inside a VS package

I'm doing a VS package that has a DynamicItemStart button inside a Menu. I don't have any problem by loading the contents of the Dynamic button when VS starts, but I'm trying to add more commands to its contents after some events like Open a project for example. I add the new commands to this "Place holder" button but I cannot see the Visual Studio UI updated. I have tried the UpdateUI Command:

Microsoft.VisualStudio.Shell.ServiceProvider serviceProvider = new Microsoft.VisualStudio.Shell.ServiceProvider(((DTE)Microsoft.VisualStudio.Shell.ServiceProvider.GlobalProvider.GetService(typeof(DTE))) as Microsoft.VisualStudio.OLE.Interop.IServiceProvider);
IVsUIShell uiShell = serviceProvider.GetService(typeof(SVsUIShell)) as IVsUIShell;
uiShell.UpdateCommandUI(1);

I'm calling this code at the BeforeQueryStatus event of the Button, but this doesn't work. Does anyone has achieved anything similar?

Any hints are really appreciated.

Edit 1: Here's the code I use to add the new commands

private void InitMRUMenu(ref OleMenuCommandService mcs)
{
  InitializeMRUList();
  if (_connectionsList != null)
  {
    int i = 0; 
    foreach (var conn in _connectionsList)
    {
        var cmdID = new CommandID(GuidList.guidAdvancedVSCTSampleCmdSet, this.baseMRUID + i);
        var mc = new OleMenuCommand(new EventHandler(OnMRUExec), cmdID);
        mruList.Add(conn.DisplayName);
        mc.BeforeQueryStatus += new EventHandler(OnMRUQueryStatus);
        mcs.AddCommand(mc);
        i++;
    }        
  }
}

private void OnMRUQueryStatus(object sender, EventArgs e)
{
  OleMenuCommand menuCommand = sender as OleMenuCommand;
  if (null != menuCommand)
  {
    int MRUItemIndex = menuCommand.CommandID.ID - this.baseMRUID;
    if (MRUItemIndex >= 0 && MRUItemIndex < this.mruList.Count)
    {
      menuCommand.Text = this.mruList[MRUItemIndex] as string;
    }       
  }
}

private void OnMRUExec(object sender, EventArgs e)
{
  //Do some actions
}

You need to add some code to the implementation of your IOleCommandTarget.QueryStatus, something like this (in C#):

int IOleCommandTarget.QueryStatus(ref Guid cmdGroup, uint cCmds, OLECMD[] prgCmds, IntPtr pCmdText)
{
    if (cmdGroup == yourCommandSet)
    {
        if (prgCmds[0].cmdID >= yourDynamicId && prgCmds[0].cmdID < (yourDynamicId + 16)) // suppose you want a maximum of 16 dynamic items
        {
            int index = (int)prgCmds[0].cmdID - yourDynamicId;

            OLECMDTEXT.OLECMDTEXTF flags = OLECMDTEXT.GetFlags(pCmdText);
            if (flags == OLECMDTEXT.OLECMDTEXTF.OLECMDTEXTF_NAME)
            {
                OLECMDTEXT.SetText(pCmdText, "yourText" + index);
            }

            prgCmds[0].cmdf = (uint)(OLECMDF.OLECMDF_ENABLED | OLECMDF.OLECMDF_SUPPORTED); // for example
        }
    }
}

Of course, the associated IOleCommandTarget.Exec must be also modified to correspond (using the same compute index).

The OLECMDTEXT is a pretty hacky utility class that can be found on various places on the internet, here it is:

/// <devdoc>
/// Helper class for setting the text parameters to OLECMDTEXT structures.
/// </devdoc>
internal static class OLECMDTEXT
{
    /// <summary>
    /// Flags for the OLE command text
    /// </summary>
    public enum OLECMDTEXTF
    {
        /// <summary>No flag</summary>
        OLECMDTEXTF_NONE = 0,
        /// <summary>The name of the command is required.</summary>
        OLECMDTEXTF_NAME = 1,
        /// <summary>A description of the status is required.</summary>
        OLECMDTEXTF_STATUS = 2
    }

    /// <summary>
    /// Gets the flags of the OLECMDTEXT structure
    /// </summary>
    /// <param name="pCmdTextInt">The structure to read.</param>
    /// <returns>The value of the flags.</returns>
    public static OLECMDTEXTF GetFlags(IntPtr pCmdTextInt)
    {
        if (pCmdTextInt == IntPtr.Zero)
            return OLECMDTEXTF.OLECMDTEXTF_NONE;

        Microsoft.VisualStudio.OLE.Interop.OLECMDTEXT pCmdText = (Microsoft.VisualStudio.OLE.Interop.OLECMDTEXT)Marshal.PtrToStructure(pCmdTextInt, typeof(Microsoft.VisualStudio.OLE.Interop.OLECMDTEXT));

        if ((pCmdText.cmdtextf & (int)OLECMDTEXTF.OLECMDTEXTF_NAME) != 0)
            return OLECMDTEXTF.OLECMDTEXTF_NAME;

        if ((pCmdText.cmdtextf & (int)OLECMDTEXTF.OLECMDTEXTF_STATUS) != 0)
            return OLECMDTEXTF.OLECMDTEXTF_STATUS;

        return OLECMDTEXTF.OLECMDTEXTF_NONE;
    }

    /// <devdoc>
    /// Accessing the text of this structure is very cumbersome.  Instead, you may
    /// use this method to access an integer pointer of the structure.
    /// Passing integer versions of this structure is needed because there is no
    /// way to tell the common language runtime that there is extra data at the end of the structure.
    /// </devdoc>
    public static string GetText(IntPtr pCmdTextInt)
    {
        Microsoft.VisualStudio.OLE.Interop.OLECMDTEXT pCmdText = (Microsoft.VisualStudio.OLE.Interop.OLECMDTEXT)Marshal.PtrToStructure(pCmdTextInt, typeof(Microsoft.VisualStudio.OLE.Interop.OLECMDTEXT));

        // Get the offset to the rgsz param.
        IntPtr offset = Marshal.OffsetOf(typeof(Microsoft.VisualStudio.OLE.Interop.OLECMDTEXT), "rgwz");

        // Punt early if there is no text in the structure.
        if (pCmdText.cwActual == 0)
            return String.Empty;

        char[] text = new char[pCmdText.cwActual - 1];
        Marshal.Copy((IntPtr)((long)pCmdTextInt + (long)offset), text, 0, text.Length);
        StringBuilder s = new StringBuilder(text.Length);
        s.Append(text);
        return s.ToString();
    }

    /// <include file='doc\NativeMethods.uex' path='docs/doc[@for="OLECMDTEXTF.SetText"]/*' />
    /// <devdoc>
    /// Accessing the text of this structure is very cumbersome.  Instead, you may
    /// use this method to access an integer pointer of the structure.
    /// Passing integer versions of this structure is needed because there is no
    /// way to tell the common language runtime that there is extra data at the end of the structure.
    /// </devdoc>
    /// <summary>
    /// Sets the text inside the structure starting from an integer pointer.
    /// </summary>
    /// <param name="pCmdTextInt">The integer pointer to the position where to set the text.</param>
    /// <param name="text">The text to set.</param>
    public static void SetText(IntPtr pCmdTextInt, string text)
    {
        Microsoft.VisualStudio.OLE.Interop.OLECMDTEXT pCmdText = (Microsoft.VisualStudio.OLE.Interop.OLECMDTEXT)Marshal.PtrToStructure(pCmdTextInt, typeof(Microsoft.VisualStudio.OLE.Interop.OLECMDTEXT));
        char[] menuText = text.ToCharArray();

        // Get the offset to the rgsz param.  This is where we will stuff our text
        IntPtr offset = Marshal.OffsetOf(typeof(Microsoft.VisualStudio.OLE.Interop.OLECMDTEXT), "rgwz");
        IntPtr offsetToCwActual = Marshal.OffsetOf(typeof(Microsoft.VisualStudio.OLE.Interop.OLECMDTEXT), "cwActual");

        // The max chars we copy is our string, or one less than the buffer size,
        // since we need a null at the end.
        int maxChars = Math.Min((int)pCmdText.cwBuf - 1, menuText.Length);

        Marshal.Copy(menuText, 0, (IntPtr)((long)pCmdTextInt + (long)offset), maxChars);

        // append a null character
        Marshal.WriteInt16((IntPtr)((long)pCmdTextInt + (long)offset + maxChars * 2), 0);

        // write out the length +1 for the null char
        Marshal.WriteInt32((IntPtr)((long)pCmdTextInt + (long)offsetToCwActual), maxChars + 1);
    }
}