' Copyright 2012 ESRI
' 
' All rights reserved under the copyright laws of the United States
' and applicable international laws, treaties, and conventions.
' 
' You may freely redistribute and use this sample code, with or
' without modification, provided you include the original copyright
' notice and use restrictions.
' 
' See the use restrictions.
' 

Imports ESRI.ArcGIS.esriSystem
Imports ESRI.ArcGIS.Catalog
Imports ESRI.ArcGIS.Display
Imports System.Runtime.InteropServices

<ComClass(clsGxStyleGalleryClass.ClassId, clsGxStyleGalleryClass.InterfaceId, clsGxStyleGalleryClass.EventsId), _
 ProgId("CustomRootObjectVBNET.clsGxStyleGalleryClass")> _
Public Class clsGxStyleGalleryClass
    Implements ESRI.ArcGIS.Catalog.IGxObject
    Implements ESRI.ArcGIS.Catalog.IGxObjectContainer


#Region "COM GUIDs"
    ' These  GUIDs provide the COM identity for this class 
    ' and its COM interfaces. If you change them, existing 
    ' clients will no longer be able to access the class.
    Public Const ClassId As String = "42d4d338-936c-4a71-a02d-577047740007"
    Public Const InterfaceId As String = "afa9eff2-7195-48ba-b025-d7daf973c453"
    Public Const EventsId As String = "a971370b-baf7-4634-b71d-9839eeb9ea00"
#End Region

    ' A creatable COM class must have a Public Sub New() 
    ' with no parameters, otherwise, the class will not be 
    ' registered in the COM registry and cannot be created 
    ' via CreateObject.

#Region "Member Variable"
    Private m_pParent As clsGxStyleGallery
    Private m_pCatalog As IGxCatalog
    Private m_pClass As IStyleGalleryClass
    Private m_pChildren As IGxObjectArray
    Private m_childrenLoaded As Boolean
#End Region

    Public Sub New()
        MyBase.New()
        m_pChildren = New GxObjectArray
        m_childrenLoaded = False
    End Sub
    Public WriteOnly Property StyleGalleryClass() As IStyleGalleryClass
        Set(ByVal value As IStyleGalleryClass)
            m_pClass = value
        End Set
    End Property
    Public Sub PreviewItem(ByVal pItem As IStyleGalleryItem, ByVal hDC As Long, ByVal r As tagRECT)
        'Draw a representation of the item to the given DC.
        m_pClass.Preview(pItem.Item, hDC, r)
    End Sub
    Public Sub Attach(ByVal Parent As ESRI.ArcGIS.Catalog.IGxObject, ByVal pCatalog As ESRI.ArcGIS.Catalog.IGxCatalog) Implements ESRI.ArcGIS.Catalog.IGxObject.Attach
        m_pParent = Parent
        m_pCatalog = pCatalog
    End Sub

    Public ReadOnly Property BaseName() As String Implements ESRI.ArcGIS.Catalog.IGxObject.BaseName
        Get
            BaseName = m_pClass.Name
        End Get
    End Property

    Public ReadOnly Property Category() As String Implements ESRI.ArcGIS.Catalog.IGxObject.Category
        Get
            Category = "Style Gallery Class"
        End Get
    End Property

    Public ReadOnly Property ClassID1() As ESRI.ArcGIS.esriSystem.UID Implements ESRI.ArcGIS.Catalog.IGxObject.ClassID
        Get
            ClassID1 = Nothing
        End Get
    End Property

    Public Sub Detach() Implements ESRI.ArcGIS.Catalog.IGxObject.Detach
        'It is our responsibility to detach all our children before deleting them.
        'This is to avoid circular referencing problems.
        Dim i As Long
        For i = 0 To m_pChildren.Count
            m_pChildren.Item(i).Detach()
        Next
        m_pParent = Nothing
        m_pCatalog = Nothing
    End Sub

    Public ReadOnly Property FullName() As String Implements ESRI.ArcGIS.Catalog.IGxObject.FullName
        Get
            FullName = m_pClass.Name
        End Get
    End Property

    Public ReadOnly Property InternalObjectName() As ESRI.ArcGIS.esriSystem.IName Implements ESRI.ArcGIS.Catalog.IGxObject.InternalObjectName
        Get
            InternalObjectName = Nothing
        End Get
    End Property

    Public ReadOnly Property IsValid() As Boolean Implements ESRI.ArcGIS.Catalog.IGxObject.IsValid
        Get
            IsValid = True
        End Get
    End Property

    Public ReadOnly Property Name() As String Implements ESRI.ArcGIS.Catalog.IGxObject.Name
        Get
            Name = m_pClass.Name
        End Get
    End Property

    Public ReadOnly Property Parent() As ESRI.ArcGIS.Catalog.IGxObject Implements ESRI.ArcGIS.Catalog.IGxObject.Parent
        Get
            Parent = m_pParent
        End Get
    End Property

    Public Sub Refresh() Implements ESRI.ArcGIS.Catalog.IGxObject.Refresh
        'Unload and reload the children.
        m_pChildren.Empty()
        m_childrenLoaded = False
        LoadChildren()
    End Sub

    Public Function AddChild(ByVal child As ESRI.ArcGIS.Catalog.IGxObject) As ESRI.ArcGIS.Catalog.IGxObject Implements ESRI.ArcGIS.Catalog.IGxObjectContainer.AddChild

    End Function

    Public ReadOnly Property AreChildrenViewable() As Boolean Implements ESRI.ArcGIS.Catalog.IGxObjectContainer.AreChildrenViewable
        Get
            AreChildrenViewable = True
        End Get
    End Property

    Public ReadOnly Property Children() As ESRI.ArcGIS.Catalog.IEnumGxObject Implements ESRI.ArcGIS.Catalog.IGxObjectContainer.Children
        Get
            LoadChildren()
            Children = m_pChildren
        End Get
    End Property

    Public Sub DeleteChild(ByVal child As ESRI.ArcGIS.Catalog.IGxObject) Implements ESRI.ArcGIS.Catalog.IGxObjectContainer.DeleteChild

    End Sub

    Public ReadOnly Property HasChildren() As Boolean Implements ESRI.ArcGIS.Catalog.IGxObjectContainer.HasChildren
        Get
            HasChildren = True
        End Get
    End Property

    Private Sub LoadChildren()
        If m_childrenLoaded Then Exit Sub

        'Our children are GxContainer objects that represent the actual style items
        'of a certain type.

        Dim pEnumItems As IEnumStyleGalleryItem
        Dim pItem As IStyleGalleryItem
        Try
            pEnumItems = m_pParent.StyleGallery.Items(m_pClass.Name, "ESRI.style", "")
            pItem = pEnumItems.Next
            While (Not pItem Is Nothing)
                Dim pGxItem As clsGxStyleGalleryItem
                pGxItem = New clsGxStyleGalleryItem
                pGxItem.StyleGalleryItem = pItem

                Dim pGxObject As IGxObject
                pGxObject = pGxItem
                pGxObject.Attach(Me, m_pCatalog)

                m_pChildren.Insert(-1, pGxObject)
                pItem = pEnumItems.Next
            End While
            m_childrenLoaded = True
        Catch ex As Exception

        Finally
            pEnumItems = Nothing
            pItem = Nothing
        End Try
    End Sub

End Class