' Copyright 2011 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.
' 

' Illustrates how to change the renderers of existing layers in a pooled ArcGIS Server map service
' using Web ADF controls and ArcObjects.  The layers are modified in a shallowly stateful way, meaning
' that the changes persist in the user's browser, but do not affect the appearance of the map service
' when viewed by other clients.

Imports Microsoft.VisualBasic
Imports System
Public Partial Class ChangeRenderer_ADF
  Inherits System.Web.UI.Page

#Region "Instance Variable Declarations"
    Private _callbackResultCollection As ESRI.ArcGIS.ADF.Web.UI.WebControls.CallbackResultCollection = New ESRI.ArcGIS.ADF.Web.UI.WebControls.CallbackResultCollection()
    Private _serverObjectStateModifier As ServerObjectStateModifier = Nothing
#End Region

#Region "ASP.NET Page Life Cycle Event Handlers"

    Public Sub Page_PreInit(ByVal sender As Object, ByVal eventArgs As System.EventArgs)
        ' Instantiate a ServerObjectStateModifier object to use for adding and removing the dynamic layer
        _serverObjectStateModifier = New ServerObjectStateModifier()
    End Sub

    Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs)
        Try
            'Register the Change and Reset Renderers buttons so they initiate asynchronous
            'postbacks when clicked
            ScriptManager1.RegisterAsyncPostBackControl(ChangeRenderersButton)
            ScriptManager1.RegisterAsyncPostBackControl(ResetRenderersButton)
            ' If the renderers have been changed (indicated by the session variable), then we need to re-apply them
            ' so that the Web ADF components accessing the changed map resources are aware of the change.  
            If (Not Session("RendererChanged") Is Nothing) AndAlso CBool(Session("RendererChanged")) Then
                ChangeRenderers(ServerObjectStateModifier.RendererAction.ApplyLast)
            End If

            AddHandler MapResourceManager1.ResourcesDispose, AddressOf MapResourceManager1_ResourcesDispose
        Catch exception As System.Exception
            ' Check whether the page is loading asynchronously.  
            If ScriptManager1.IsInAsyncPostBack Then
                ' Get a callback result that will show an alert with information pertaining to the exception
                Dim errorCallbackResult As ESRI.ArcGIS.ADF.Web.UI.WebControls.CallbackResult = Utility.GetErrorCallback(exception)
                ' Get the control that initiated the postback
                Dim control As System.Web.UI.Control = Utility.GetPostBackControl(Page)

                ' If the control is a Web ADF Control (i.e. WebCotnrol or CompositeControl), add the error 
                ' callback to that control's callback results.  Otherwise, add the error callback to the 
                ' callback results collection member variable, which will be passed to the client in 
                ' GetCallbackResult.
                If TypeOf control Is ESRI.ArcGIS.ADF.Web.UI.WebControls.WebControl Then
                    Dim adfWebControl As ESRI.ArcGIS.ADF.Web.UI.WebControls.WebControl = TryCast(control, ESRI.ArcGIS.ADF.Web.UI.WebControls.WebControl)
                    adfWebControl.CallbackResults.Add(errorCallbackResult)
                ElseIf TypeOf control Is ESRI.ArcGIS.ADF.Web.UI.WebControls.CompositeControl Then
                    Dim adfCompositeControl As ESRI.ArcGIS.ADF.Web.UI.WebControls.CompositeControl = TryCast(control, ESRI.ArcGIS.ADF.Web.UI.WebControls.CompositeControl)
                    adfCompositeControl.CallbackResults.Add(errorCallbackResult)
                Else
                    _callbackResultCollection.Add(errorCallbackResult)
                    ScriptManager1.RegisterDataItem(Page, _callbackResultCollection.ToString(), False)
                End If
            Else
                ' Since the page is in full postback, write the javascript alert code directly to the response
                Dim jsErrorAlert As String = String.Format("<script>{0}</script>", Utility.GetJavaScriptErrorString(exception))
                Response.Write(jsErrorAlert)
            End If
        End Try
    End Sub

#End Region

#Region "Web ADF Control Event Handlers"

    ' If the resources' renderers have been changed (indicated by the session variable), then we need to restore them to 
    ' their original state before the server context created as a result of the current page request is released.  
    ' Otherwise, the altered renderers will be applied to the map service outside the scope of this request, meaning they 
    ' will be seen by other clients using the service.
    Private Sub MapResourceManager1_ResourcesDispose(ByVal sender As Object, ByVal e As System.EventArgs)
        If (Not Session("RendererChanged") Is Nothing) AndAlso CBool(Session("RendererChanged")) Then
            ChangeRenderers(ServerObjectStateModifier.RendererAction.ApplyOriginal)
        End If
    End Sub

#End Region

#Region "ASP.NET Web Control Event Handlers"

    Public Sub ResetRenderersButton_Click(ByVal sender As Object, ByVal e As System.EventArgs)
        Try
            ChangeRenderers(ServerObjectStateModifier.RendererAction.ApplyOriginal)
            RefreshResourcesAndToc()

            ' Set the session variables indicating that renderers for the resources in the map are in their  
            ' original state.  We do this to share this information with the custom map handler.
            Session("RendererChanged") = False
        Catch exception As System.Exception
            ' Get a callback result that will alert the user of the error and add it to the callback results collection
            Dim errorCallbackResult As ESRI.ArcGIS.ADF.Web.UI.WebControls.CallbackResult = Utility.GetErrorCallback(exception)
            _callbackResultCollection.Add(errorCallbackResult)
            ScriptManager1.RegisterDataItem(Page, _callbackResultCollection.ToString(), False)
        End Try
    End Sub

    Public Sub ChangeRenderersButton_Click(ByVal sender As Object, ByVal e As System.EventArgs)
        Try
            ChangeRenderers(ServerObjectStateModifier.RendererAction.ApplyNew)
            RefreshResourcesAndToc()

            ' Set the session variable indicating that renderers for the resources in the map have been changed.  
            ' We do this to share this information with the custom map handler.
            Session("RendererChanged") = True
        Catch exception As System.Exception
            ' Get a callback result that will alert the user of the error and add it to the callback results collection
            Dim errorCallbackResult As ESRI.ArcGIS.ADF.Web.UI.WebControls.CallbackResult = Utility.GetErrorCallback(exception)
            _callbackResultCollection.Add(errorCallbackResult)
            ScriptManager1.RegisterDataItem(Page, _callbackResultCollection.ToString(), False)
        End Try
    End Sub

#End Region

#Region "Instance Methods"

    ' Refreshes the Toc and all the resources in the Map
    Private Sub RefreshResourcesAndToc()
        For Each mapResourceItem As ESRI.ArcGIS.ADF.Web.UI.WebControls.MapResourceItem In MapResourceManager1.ResourceItems
            Map1.RefreshResource(mapResourceItem.Name)
        Next mapResourceItem

        Toc1.Refresh()
        Map1.CallbackResults.CopyFrom(Toc1.CallbackResults)

        _callbackResultCollection.CopyFrom(Map1.CallbackResults)
        ScriptManager1.RegisterDataItem(Page, _callbackResultCollection.ToString(), False)
    End Sub

    ' Makes sure each resource in the map is initialized, then uses the ServerObjectStateModifier to apply random simple 
    ' renderers to its layers
    Private Sub ChangeRenderers(ByVal rendererAction As ServerObjectStateModifier.RendererAction)
        For Each mapResourceItem As ESRI.ArcGIS.ADF.Web.UI.WebControls.MapResourceItem In MapResourceManager1.ResourceItems
            If TypeOf mapResourceItem.Resource Is ESRI.ArcGIS.ADF.Web.DataSources.ArcGISServer.MapResourceLocal Then
                _serverObjectStateModifier.ApplySimpleRenderers(TryCast(mapResourceItem.Resource, ESRI.ArcGIS.ADF.Web.DataSources.ArcGISServer.MapResourceLocal), rendererAction)
            End If
        Next mapResourceItem
    End Sub

#End Region


End Class