protected override void RenderItemTemplateItems(IEnumerable source)
{
if (GroupItemTemplate != null)
{
var cachedResult = new List <KeyValuePair <String, RenderContext> >();
foreach (var sourceItem in source)
{
var cachedOutput = CurrentContext.CreateChildContext();
ItemTemplate.DataContext = sourceItem;
ItemTemplate.Render(cachedOutput);
cachedResult.Add(new KeyValuePair <string, RenderContext>(ItemTemplate.Group ?? "", cachedOutput));
}
var groupsList = cachedResult
.Where(g => !String.IsNullOrEmpty(g.Key))
.Select(g => g.Key)
.Distinct()
.ToList();
if (groupsList.Count > 0)
{
var template = GroupItemTemplate;
template.Children.Clear();
List <RenderContext> currentItems = new List <RenderContext>();
HtmlObjectDelegate renderAction = (control) =>
{
foreach (var ctx in currentItems)
{
ctx.JoinToParent();
}
};
template.RenderContentEvent += renderAction;
foreach (var groupName in groupsList)
{
currentItems.Clear();
currentItems.AddRange(cachedResult
.Where(g => g.Key == groupName)
.Select(g => g.Value));
template.DataContext = groupName;
template.Render(CurrentContext);
}
template.RenderContentEvent -= renderAction;
}
else
{
cachedResult.ForEach(c => c.Value.JoinToParent());
}
}
else
{
foreach (var sourceItem in source)
{
ItemTemplate.DataContext = sourceItem;
ItemTemplate.Render(CurrentContext);
}
}
}
public static T OnPostRender <T>(this T control, HtmlObjectDelegate handler) where T : HtmlObject
{
control.PostRenderEvent += handler;
return(control);
}
public static T OnDataBind <T>(this T control, HtmlObjectDelegate handler) where T : HtmlObject
{
control.DataBindEvent += handler;
return(control);
}
public static T OnRenderContent <T>(this T control, HtmlObjectDelegate handler) where T : HtmlObject
{
control.RenderContentEvent += handler;
return(control);
}