' 
' (C) Copyright 2003-2014 by Autodesk, Inc.
' 
' Permission to use, copy, modify, and distribute this software in
' object code form for any purpose and without fee is hereby granted,
' provided that the above copyright notice appears in all copies and
' that both that copyright notice and the limited warranty and
' restricted rights notice below appear in all supporting
' documentation.
'
' AUTODESK PROVIDES THIS PROGRAM "AS IS" AND WITH ALL FAULTS.
' AUTODESK SPECIFICALLY DISCLAIMS ANY IMPLIED WARRANTY OF
' MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE.  AUTODESK, INC.
' DOES NOT WARRANT THAT THE OPERATION OF THE PROGRAM WILL BE
' UNINTERRUPTED OR ERROR FREE.
' 
' Use, duplication, or disclosure by the U.S. Government is subject to
' restrictions set forth in FAR 52.227-19 (Commercial Computer
' Software - Restricted Rights) and DFAR 252.227-7013(c)(1)(ii)
' (Rights in Technical Data and Computer Software), as applicable.
'
Imports Autodesk
Imports Autodesk.Revit.DB

<Autodesk.Revit.Attributes.Transaction(Autodesk.Revit.Attributes.TransactionMode.Manual)> _
<Autodesk.Revit.Attributes.Regeneration(Autodesk.Revit.Attributes.RegenerationOption.Manual)> _
<Autodesk.Revit.Attributes.Journaling(Autodesk.Revit.Attributes.JournalingMode.NoCommandData)> _
Public Class Command

    Implements Autodesk.Revit.UI.IExternalCommand

    ''' <summary>
    ''' Implement this method as an external command for Revit.
    ''' </summary>
    ''' <param name="commandData">An object that is passed to the external application 
    ''' which contains data related to the command, 
    ''' such as the application object and active view.</param>
    ''' <param name="message">A message that can be set by the external application 
    ''' which will be displayed if a failure or cancellation is returned by 
    ''' the external command.</param>
    ''' <param name="elements">A set of elements to which the external application 
    ''' can add elements that are to be highlighted in case of failure or cancellation.</param>
    ''' <returns>Return the status of the external command. 
    ''' A result of Succeeded means that the API external method functioned as expected. 
    ''' Cancelled can be used to signify that the user cancelled the external operation 
    ''' at some point. Failure should be returned if the application is unable to proceed with 
    ''' the operation.</returns>
    Public Function Execute(ByVal commandData As Autodesk.Revit.UI.ExternalCommandData, _
        ByRef message As String, ByVal elements As Autodesk.Revit.DB.ElementSet) _
        As Autodesk.Revit.UI.Result Implements Autodesk.Revit.UI.IExternalCommand.Execute

        ' Setup a default message in case any exceptions are thrown that we have not
        ' explicitly handled. On failure the message will be displayed by Revit
        message = "The sample failed"
        Execute = Autodesk.Revit.UI.Result.Failed

        Try
            Dim application As Autodesk.Revit.ApplicationServices.Application = commandData.Application.Application

            Dim filter As Autodesk.Revit.DB.ElementClassFilter
            filter = New Autodesk.Revit.DB.ElementClassFilter(GetType(Autodesk.Revit.DB.DesignOption))
            Dim collector As Autodesk.Revit.DB.FilteredElementCollector
            collector = New Autodesk.Revit.DB.FilteredElementCollector(commandData.Application.ActiveUIDocument.Document)
            collector.WherePasses(filter)
            Dim iter As IEnumerator
            iter = collector.GetElementIterator

            Dim element As Autodesk.Revit.DB.Element
            Dim designOptions As New ElementSet()

            'iterate through all the elements, looking for design option elements
            Do While iter.MoveNext()

                element = iter.Current
                If TypeOf element Is Autodesk.Revit.DB.DesignOption Then
                    designOptions.Insert(element)
                End If

            Loop

            'if we found any design options then display them in a dialog
            If designOptions.Size > 0 Then
                Dim dialog As New DesignOptionsDialog()

                For Each element In designOptions
                    dialog.DesignOptionsList.Items.Add(element.Name)
                Next

                dialog.ShowDialog()

            Else
                MsgBox("There are no design options in this document")
            End If

            ' change our result to successful
            Execute = Autodesk.Revit.UI.Result.Succeeded
            Return Execute
        Catch ex As Exception
            message = ex.Message
            Return Execute
        End Try

    End Function
End Class