WinForms has the SortedBindingList.vb for sorting. But it appears sorting is not supported at this time in WebForms. The only thing I see that comes close is the “CanSort” method on CSLADataSourceView, which hardcoded to "False".
Am I missing something? Has anybody solved this issue in a way that doesn’t require a round trip with each new sort?
vivus:
public SortedBindingList<TransactionWebView> GetTransactionWebViewList() {
object businessObject1 =
HttpContext.Current.Session["transactions"];
if (businessObject1 == null ||
!(businessObject1 is SortedBindingList<TransactionWebView>)) {
businessObject1 = new SortedBindingList<TransactionWebView>(
TransactionWebViewList.GetTransactionWebViewList(this.User.ContactID, false));
UpdateTransactionWebViewList((SortedBindingList<TransactionWebView>)businessObject1);
}
return (SortedBindingList<TransactionWebView>)businessObject1;
}
public void UpdateTransactionWebViewList(SortedBindingList<TransactionWebView> obj) {
HttpContext.Current.Session["transactions"] = obj;
}
Had a dickens of a time to get this to compile. Finally realized there are two BO library objects being used, not one. TransactionWebView and TransactionWebViewList, representing the item object and the collection object respectively.
Thought I would point it out for others like me who are suffering from a "slow brain day". :)
vivus:
... now for overriding the sorting method of the grid...
ListDirection requires a "using System.ComponentModel;" directive.
After that, it worked like a charm!
Thanks!
I don't know if this will be the approriate solution or its efficient. In my case I use ReadOnlyList but surely it will worked with BusinessBaseList. First, I wrapped my ReadOnlyList with SortedBindingList. Please see code below.
Public Class SortedYourReadOnlyList
Inherits SortedBindingList(Of YourReadOnlyBase)
Private Sub New(ByVal l As YourReadOnlyList)
MyBase.New(l)
End Sub
Public Shared Function NewSortedYourReadOnlyList(ByVal l As ReadOnlyList) As SortedYourReadOnlyList
Return New SortedTimesheetList(l)
End Function
End Class
As you can noticed, it wont worked in ASP.NET 2.0 when you clicked the sorted columns compared to winforms. So I decided to trigger the sorting programatically. I used the GridView_Sorting() event to get the column to be sorted and what direction. I store the Gridview sorting event handler in a session then. Please see code below:
Protected Sub GridView1_Sorting(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.GridViewSortEventArgs) Handles grdTimesheet.Sorting
Session("willSort") = e
End Sub
Protected Sub XXX_SelectObject(ByVal sender As Object, ByVal e As Csla.Web.SelectObjectArgs) Handles XXX.SelectObject
If Session("YourSortedReadOnlyList") Is Nothing Then
Session("YourSortedReadOnlyList") = YourSortedReadOnlyList.NewYourSortedReadOnyList( _
YourReadOnlyList.GetList(New Criteria(Your Criteria)))
End If
If Session("willSort") IsNot Nothing Then
Dim _sort As GridViewSortEventArgs = Session("willSort")
Dim _slist As YourSortedReadOnlyList = CType(Session("YourSortedReadOnlyList"), YourSortedReadOnlyList)
_slist.ApplySort(_sort.SortExpression, _sort.SortDirection)
Session("YourSortedReadOnlyList") = _slist
Session("willSort") = Nothing
EndIf
e.BusinessObject = Session("YourSortedReadOnlyList")
Virus, its so funny your posting in C# and I'm posting in VB.NET. At least the other readers could have an option then. But more or less, I think we do have same solution. V
Cheers,
Glenn
I am having this same problem for a while now, but i was wondering if anyone was able to figure out the actual reason of this problem, and maybe something that is more like a fix than a work-around?
thanks,
Fabio
This is just the design of CSLA, but I found a pretty clean way to implement in code behind rather than carrying things around in session - just do the sort when selecting:
protected void CslaDataSource1_SelectObject(object sender, Csla.Web.SelectObjectArgs e){
SortedYourList list = SortedYourList.NewSortedYourList(YourList.FactoryMethod()); if (GridView1.SortExpression != string.Empty){
switch (GridView1.SortDirection){
case SortDirection.Ascending:list.ApplySort(GridView1.SortExpression,
ListSortDirection.Ascending); break; case SortDirection.Descending:list.ApplySort(GridView1.SortExpression,
ListSortDirection.Descending); break;}
}
e.BusinessObject = list;
}
BOO:
My EditableObject list does not have ApplySort() but you have list.ApplySort(). Do you added your own ApplySort or something else?
I am having a problem with the gridview and filteredbindinglist in how best to databind the filtered list.
The cslaDataSource_SelectObject fires when a user wishes to sort a column, the list is obtained, sorted then set back to the grid like e.businessobject = sortedList. That works great, but how can I do this for a filteredBindingList? I want to be able to let the user entered a filtered value into a text box and have the filter begin by pressing a button on the web form. The button event fires, the list is filtered but I do not know how to set the datagrids binding to show this filtered list.
I know this is a really old post but perhaps I have something to add.
Sorting should happen in the UI, not the business object. So if you are using .net 2.0, CSLA 2.0 you should be using the sortedBindingList as described on page 247 (C# 2005).
Get the normal collection then create a sortedBindingList, then execute the "ApplySort" method.
Then bind the sorted list to the grid.
NormalCollection nc = getCollection();
Csla.SortedBindingList<NormalCollection > sortedList = new Csla.SortedBindingList<NormalCollection >(nc);
sortedList.ApplySort("Property", System.ComponentModel.ListSortDirection.Descending);
this.gv.DataSource = sortedList;
this.gv.DataBind();
In .net 3.5 LINQ should be used.
Here's what I found after almost a day of searching. I feel this is quick and easy and reusable!
Using statements needed:
using
System.Collections.Generic;using
System.Linq.Expressions;
Create a static class:
public static class MyExtensions{
public static IEnumerable<T> Sort<T>(IEnumerable<T> source, string sortExpression, SortDirection sortDirection){
var _param = Expression.Parameter(typeof(T), "item"); var _sortExpression = Expression.Lambda<Func<T, object>>(
Expression.Convert(Expression.Property(_param, sortExpression), typeof(object)), _param); if (sortDirection == SortDirection.Descending) return source.AsQueryable<T>().OrderByDescending<T, object>(_sortExpression); else return source.AsQueryable<T>().OrderBy<T, object>(_sortExpression);}
}
Call it using the following:
IEnumerable<PromotionPlanning.Utilities.Classes.EventInfo> eventList;
protected void EventListDataSource_SelectObject(object sender, Csla.Web.SelectObjectArgs e)
{
eventList =
from f in GetProdEventList()
select f;
if (gvEventList.SortExpression.Length > 0)
{
eventList = MyExtensions.Sort<EventInfo>(eventList, gvEventList.SortExpression, gvEventList.SortDirection);
}
e.BusinessObject = eventList;
}
Enjoy!
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