Filtering News etc. by category

Posted by Community Admin on 15-Feb-2012 00:00

So far as I can tell, there are only two ways to filter content by category: either by setting a fixed category in the module properties, or by dropping a categories widget onto the module's page. What I'd like to be able to set a session variable and have the content filter based on that, without the user having to select the category as they navigate from page to page. In my specific application, I want users to be able to pick a city at the beginning of their session and then filter all of my content based on that city.

One approach I had been considering is creating a new categories widget, based on the existing Categories widget, and then have it set its state based on a session variable. There is an article that describes how to customize Sitefinity widgets, I tried following these instructions but I could not even find the Categories widget under Settings/System/ApplicationModules.

Any suggestions would be greatly appreciated.

Thanks!

Posted by Community Admin on 20-Feb-2012 00:00

Hi,

It's possible to achieve the desired functionality with not that much modification, and preserving the default look and feel of the control. You'll need to modify the default ListView as well as the Template.Please consider the following sample, based on the NewsView built in control.
1) We need to override the list mode of the control. This will allow us to add additional logic and control. To do so create a custom control which inherits from MasterListView:

using System;

using System.Linq;

using System.Web.UI.WebControls;

using Telerik.Sitefinity.GenericContent.Model;

using Telerik.Sitefinity.Model;

using Telerik.Sitefinity.Modules.News.Web.UI;

using Telerik.Sitefinity.News.Model;

using Telerik.Sitefinity.Taxonomies;

using Telerik.Sitefinity.Taxonomies.Model;

using Telerik.Web.UI;

namespace SitefinityWebApp.CustomControls

public class CustomMasterListView: MasterListView

public override string LayoutTemplatePath

get

return "~/CustomControls/TitlesDatesListView.ascx";

set

base.LayoutTemplatePath = value;

public virtual RadComboBox CategoriesCombo

get

return this.Container.GetControl<RadComboBox>("categoriesCombo", false);

public virtual Button FilterButton

get

return this.Container.GetControl<Button>("filterBtn", false);

protected override void

InitializeControls(Telerik.Sitefinity.Web.UI.GenericContainer container, Telerik.Sitefinity.Web.UI.ContentUI.Contracts.IContentViewDefinition definition)

//create a categories dropdown.

TaxonomyManager taxonomyManager = TaxonomyManager.GetManager();

var newsCategories = taxonomyManager.GetStatistics()

.Where(tS => tS.DataItemType == "Telerik.Sitefinity.News.Model.NewsItem" && tS.TaxonomyId == TaxonomyManager.CategoriesTaxonomyId)

.Where(tS => tS.StatisticType == ContentLifecycleStatus.Live && tS.MarkedItemsCount > 0)

.Distinct()

.Select(t => new

taxonId = t.TaxonId,

taxonTitle = taxonomyManager.GetTaxon<HierarchicalTaxon>(t.TaxonId).GetString("Title"),

).ToList();

this.CategoriesCombo.DataTextField = "taxonTitle";

this.CategoriesCombo.DataValueField = "taxonId";

this.CategoriesCombo.DataSource = newsCategories;

this.CategoriesCombo.DataBind();

RadComboBoxItem emptyItem = new RadComboBoxItem("Choose category");

this.CategoriesCombo.Items.Insert(0, emptyItem);

protected override IQueryable<Telerik.Sitefinity.News.Model.NewsItem> GetItemsList(ref int? totalCount)

//check if a category to filter by is selected and add it to the filter expression

if (this.CategoriesCombo.SelectedIndex > 0)

this.FilterExpression += string.Format(" AND Category.Contains((0))", this.CategoriesCombo.SelectedValue.ToString());

//populate items list

return base.GetItemsList(ref totalCount);

protected override void OnPreRender(EventArgs e)

int? totalCount = 0;

IQueryable<NewsItem> query = this.GetItemsList(ref totalCount);

this.InitializeListView(query, totalCount);

base.OnPreRender(e);

2) Create a custom template that has the combobox and the button that causes filtration:

<%@ Control Language="C#" %>

<%@ Register TagPrefix="sf" Namespace="Telerik.Sitefinity.Web.UI.ContentUI" Assembly="Telerik.Sitefinity" %>

<%@ Register TagPrefix="sf" Namespace="Telerik.Sitefinity.Web.UI.Comments" Assembly="Telerik.Sitefinity" %>

<%@ Register TagPrefix="sf" Namespace="Telerik.Sitefinity.Web.UI" Assembly="Telerik.Sitefinity" %>

<%@ Register TagPrefix="sf" Namespace="Telerik.Sitefinity.Web.UI.PublicControls.BrowseAndEdit" Assembly="Telerik.Sitefinity" %>

<%@ Register TagPrefix="telerik" Namespace="Telerik.Web.UI" Assembly="Telerik.Web.UI" %>

<telerik:RadComboBox runat="server" ID="categoriesCombo" Skin="Sitefinity"></telerik:RadComboBox>

<asp:Button runat="server" ID="filterBtn" Text="Submit" />

<telerik:RadListView ID="NewsList" ItemPlaceholderID="ItemsContainer" runat="server" EnableEmbeddedSkins="false" EnableEmbeddedBaseStylesheet="false">

<LayoutTemplate>

<sf:ContentBrowseAndEditToolbar ID="MainBrowseAndEditToolbar" runat="server" Mode="Add"></sf:ContentBrowseAndEditToolbar>

<ul class="sfnewsList sfnewsListTitleDate">

<asp:PlaceHolder ID="ItemsContainer" runat="server" />

</ul>

</LayoutTemplate>

<ItemTemplate>

<li class="sfnewsListItem">

<h2 class="sfnewsTitle">

<sf:DetailsViewHyperLink TextDataField="Title" ToolTipDataField="Description" runat="server" />

</h2>

<div class="sfnewsMetaInfo">

<sf:FieldListView ID="PublicationDate" runat="server" Format="PublicationDate.ToLocal():MMM dd, yyyy" />

<sf:CommentsBox ID="itemCommentsLink" runat="server" CssClass="sfnewsCommentsCount"/>

</div>

<sf:ContentBrowseAndEditToolbar ID="BrowseAndEditToolbar" runat="server" Mode="Edit,Delete,Unpublish"></sf:ContentBrowseAndEditToolbar>

</li>

</ItemTemplate>

</telerik:RadListView>

<sf:Pager id="pager" runat="server"></sf:Pager>

3) Go to Administration -> Settings -> Advanced -> News -> Controls -> NewsFrontend -> Views and replace the ViewType of the list view with the custom one.

4) Enable view state on the page.

Once you place the widget on a page you'll notice the newly appeared dropdown which should be populated by the categories you have assigned to your content item. Selecting any of them and clicking the button will
automatically adjust the filter expression to match the desired category. You can modify the provided sample slightly to work with the desired Content type and implement the specific filtering functionality- the principle is the same.

Greetings,
Boyan Barnev
the Telerik team

Do you want to have your say in the Sitefinity development roadmap? Do you want to know when a feature you requested is added or when a bug fixed? Explore the Telerik Public Issue Tracking system and vote to affect the priority of the items

Posted by Community Admin on 23-May-2012 00:00

Hello Boyan,

Thanks for sharing the code, after implementing this code I am getting the news according to the applied filter but I am not able to navigate on detail page of news. So, when I click on news heading same page renders again. Any clue how can I solve this issue?

Thanks in advance

This thread is closed

All Replies