<%@ Page Language="C#"  AutoEventWireup="true" %>
<%@ Import Namespace="WEBSWAPP.Website.Data" %>
<%@ Import Namespace="System.Collections.Generic" %>
<%@ Import Namespace="System.Linq" %>
<script runat="server">
       private List<NavigationalLink> links = null;
        protected void Page_Load(object sender, EventArgs e)
            {
            //The navigational list of my website is stored in the application cache
            links = Cache["WebsiteLinks"] as List<NavigationalLink>;

            //my website is organized into categories-chapters-essays
            lvCategories.DataSource = links.Where(l => l.LinkType == LinkTypes.Category)
                    .OrderBy(l => l.Position)
                    .ToList();
            lvCategories.DataBind();

            }
        protected void lvCategories_ItemDataBound(object sender, ListViewItemEventArgs e)
            {
            if (e.Item.ItemType == ListViewItemType.DataItem)
                {
                HiddenField hfId = e.Item.FindControl("hfId") as HiddenField;
                if (hfId != null)
                    {
                    string categoryId = hfId.Value;
                    ListView lvChapters = e.Item.FindControl("lvChapters") as ListView;
                    if (lvChapters != null)
                        {

                        lvChapters.DataSource = links
                            .Where(s => s.LinkType == LinkTypes.Chapter && s.ParentNavigationalLinkId == categoryId)
                            .OrderBy(l => l.Position)
                            .ToList();
                        lvChapters.DataBind();
                        }
                    }
                }
            }
        protected void lvChapters_ItemDataBound(object sender, ListViewItemEventArgs e)
            {

            if (e.Item.ItemType == ListViewItemType.DataItem)
                {
                HiddenField hfId = e.Item.FindControl("hfId") as HiddenField;
                if (hfId != null)
                    {
                    string chapterId = hfId.Value;
                    ListView lvEssays = e.Item.FindControl("lvEssays") as ListView;
                    if (lvEssays != null)
                        {

                        lvEssays.DataSource = links
                            .Where(s => s.LinkType == LinkTypes.Essay && s.ParentNavigationalLinkId == chapterId)
                            .OrderBy(l => l.Position)
                            .ToList();
                        lvEssays.DataBind();
                        }
                    }
                }
            }
</script>
<asp:Content ID="Content1" ContentPlaceHolderID="head" runat="server">
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server">
    <h2>
        Displaying my website's TOC using nested ListView controls</h2>
    <p>
        In this demo I use 3 nested ListView controls to display the site's hierarchy. You
        will find a link to the source code at the bottom.</p>
    <%--     First level of the hierarchy of my website's TOC is the site category  --%>
    <asp:ListView ID="lvCategories" runat="server" ItemPlaceholderID="itemPlaceHolder1"
        DataKeyNames="Id" OnItemDataBound="lvCategories_ItemDataBound">
        <LayoutTemplate>
            <ul>
                <asp:PlaceHolder ID="itemPlaceHolder1" runat="server"></asp:PlaceHolder>
            </ul>
        </LayoutTemplate>
        <ItemTemplate>
            <%--     this hidden field would help me determine the primary key of the category during the ItemDataBound event handling --%>
            <asp:HiddenField ID="hfId" runat="server" Value='<%#Eval("Id") %>' />
            <li>Category
                <%#Eval("Position") %>:
                <asp:Label runat="server" ID="lblCategory" Text='<%#Eval("Text") %>' ToolTip='<%#Eval("ToolTip") %>'></asp:Label>
                <%--     Second level of the hierarchy of my website's TOC are Chapters for each category  --%>
                <asp:ListView ID="lvChapters" runat="server" ItemPlaceholderID="itemPlaceHolder2"
                    DataKeyNames="Id" OnItemDataBound="lvChapters_ItemDataBound">
                    <LayoutTemplate>
                        <ul>
                            <asp:PlaceHolder ID="itemPlaceHolder2" runat="server"></asp:PlaceHolder>
                        </ul>
                    </LayoutTemplate>
                    <ItemTemplate>
                        <asp:HiddenField ID="hfId" runat="server" Value='<%#Eval("Id") %>' />
                        <li>Chapter
                            <%#Eval("Position") %>:
                            <asp:Label runat="server" ID="lblChapter" Text='<%#Eval("Text") %>' ToolTip='<%#Eval("ToolTip") %>'></asp:Label>
                            <%--     Third level of the hierarchy of my website's TOC are the Essays (i.e. the individual demos)    --%>
                            <asp:ListView ID="lvEssays" runat="server" ItemPlaceholderID="itemPlaceHolder3" DataKeyNames="Id">
                                <LayoutTemplate>
                                    <ul>
                                        <asp:PlaceHolder ID="itemPlaceHolder3" runat="server"></asp:PlaceHolder>
                                    </ul>
                                </LayoutTemplate>
                                <EmptyDataTemplate>
                                    There are no Essays for this Chapter.</EmptyDataTemplate>
                                <ItemTemplate>
                                    <li>Essay
                                        <%#Eval("Position") %>:
                                        <asp:HyperLink ID="HyperLink1" runat="server" NavigateUrl='<%#Eval("Url") %>' Text='<%#Eval("Text") %>'
                                            ToolTip='<%#Eval("ToolTip") %>'></asp:HyperLink>
                                        <asp:Label ID="lblEssay" runat='server' Text='<%#Eval("ToolTip") %>' ToolTip='<%#Eval("ToolTip") %>'></asp:Label></li>
                                </ItemTemplate>
                            </asp:ListView>
                        </li>
                    </ItemTemplate>
                </asp:ListView>
            </li>
        </ItemTemplate>
    </asp:ListView>
</asp:Content>