| Author: Vidhya 09 Aug 2008 | Member Level: Gold | Rating:  Points: 6 |
hi,
.Create a subclass of the System.Web.UI.WebControls.Repeater class.
.Trap the ItemCreated event.
.Add a GroupTemplate template to the control (in addition to the ItemTemplate).
.For each item created, compare it to the previous item using a custom Comparer.
.If it is different, instantiate the template and databind it using the same ItemData as the current Item.
.Override the CreateChildControls method to reset the 'last record' member.
Anyway, I think this is a very good example of subclassing ASP.NET controls and I'm still wondering why this one isn't included in the standard framework.
using System;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Collections;
using System.ComponentModel;
namespace GroupedRepeater.Controls
{
/// <summary>
/// Summary description for GroupingRepeater.
/// When another group is found, render an additional template.
/// </summary>
public class GroupingRepeater : System.Web.UI.WebControls.Repeater
{
private ITemplate _groupTemplate = null;
private IComparer _comparer = null;
private static object lastvalue = null;
public GroupingRepeater()
{
this.ItemCreated += new
RepeaterItemEventHandler(GroupingRepeater_ItemCreated);
}
protected override void AddParsedSubObject(object obj)
{
base.AddParsedSubObject (obj);
}
public IComparer Comparer
{
get { return _comparer; }
set { _comparer = value; }
}
[TemplateContainer(typeof(GroupHeader))]
public ITemplate GroupTemplate
{
get
{
return _groupTemplate;
}
set
{
_groupTemplate = value;
}
}
protected override void CreateChildControls()
{
lastvalue = null;
base.CreateChildControls ();
}
private void GroupingRepeater_ItemCreated(object sender,
RepeaterItemEventArgs e)
{
System.Diagnostics.Trace.WriteLine(e.Item.GetType().Name);
if(e.Item.ItemType == ListItemType.Item ||
e.Item.ItemType == ListItemType.AlternatingItem)
{
if(e.Item.DataItem != null)
{
if(_comparer.Compare(lastvalue, e.Item.DataItem) != 0)
{
//add a header if it was different from the previous item.
GroupHeader item = new GroupHeader();
_groupTemplate.InstantiateIn(item);
item.DataItem = e.Item.DataItem;
this.Controls.Add(item);
item.DataBind();
}
}
lastvalue = e.Item.DataItem;
}
}
public class GroupHeader : Control,INamingContainer
{
private object _dataItem;
public virtual object DataItem
{
get
{
return _dataItem;
}
set
{
_dataItem = value;
}
}
}
}
}
That's it! I hope you find this useful.
Note:
Rate this content if it really helps!
|