Heyah Folks-

Strange behavior I can't seem to explain.

I have a composite server control embedded in a Data List. It is basically an image button with some added functionality to fit some specs. It works just fine when outside of a datalist - that is when it is explicitly typed in the aspx page. I assign it the proper properties in the code-behind, and then processes everything once the imagebutton is clicked.

...but it doesn't seem to work when embedded in a DataList template.

Using the ItemDataBound event of the Datalist, I assign the server control the necessary properties as such:

AddToShoppingCart AddToCart1 = (AddToShoppingCart)e.Item.FindControl("AddToCart1" );
AddToCart1.ProductID = Convert.ToInt32(productID.Text);
AddToCart1.CustomerID = Convert.ToInt32(PortalSettings.CurrentUser.Identit y.ID);

If I click on one of the server controls in runtime (which are iterated for each item in the DataList), it does indeed fire the OnClick event of the Imagebutton - but does not pass along the properties. I have verified all this in debug.

For some reason, the properties of the ServerControl are not being sent as arguments when they are embedded in a DataList.


Any help would be most appreciated.

Here is some of the code for the Server Control:

_____


using System;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using RevWorks.Modules.Ecommerce.Business;

namespace Rainbow.DesktopModules.Store.Orders.Controls
{

public class AddToShoppingCart : Control, INamingContainer
{
protected override void CreateChildControls()
{

ImageButton button = new ImageButton();
button.ImageUrl = imageUrl;
Controls.Add(button);
button.Click += new ImageClickEventHandler(this.ButtonClicked);

}


private void ButtonClicked(Object sender, ImageClickEventArgs e)
{
...process code using properties
}


public int CustomerID
{
get{...}
set{...}
}

public int ProductID
{
get{return productID;}
set{productID=value;}
}

protected int Quantity
{
get
{...}

}

public string RedirectUrl
{
get{...}
set{...}
}

private string imageUrl;
private int customerID;
private int productID;
private string redirectUrl;


}
}

Hello,

I would post the code for what you do with it in the Data List (both HTML and code-behind).

Brian

Indeed:

DATALIST:

<asp:datalist id="resultsList" Runat="server">
<ItemTemplate>
<cc1:addtoshoppingcart id="AddToCart1" runat="server" ImageUrl="../../images/addtocart.gif" />
</ItemTemplate>
</asp:datalist>


CODEBEHIND:

private void resultsList_ItemDataBound(object sender, System.Web.UI.WebControls.DataListItemEventArgs e)
{

AddToShoppingCart AddToCart1 = (AddToShoppingCart)e.Item.FindControl("AddToCart1" );

AddToCart1.ProductID = ...
AddToCart1.CustomerID = ...
AddToCart1.RedirectUrl = ...

}

Hey,

Instead of manually supplying the properties using the ItemDataBound event, try binding them directly as such:

<cc1:addtoshoppingcart id="AddToCart1" runat="server" ImageUrl="../../images/addtocart.gif"
ProductID= '<%# Databinder.Eval(Container.DataItem, "ProductID") %>'
CustomerID = '<%# Databinder.Eval(Container.DataItem, "CustomerID") %>'
RedirectUrl = '<%# Databinder.Eval(Container.DataItem, "RedirectUrl") %>'
/>

Brian

Nope...doesn't seem to keep it. When the code enters the server control after the postback, it just uses a productID of zero.

Any thoughts?

Hey,

Are you sure that when you access an item, you don't have to reference the cell, as is with the datagrid? I don't know the data list much, but does this work:

e.item.cells(0).findcontrol("AddToCart1")

Brian

Hey Brian-

Nope...no cells member of the item class. And all of the other controls in the DataList are found, populated, and present during ensuing postbacks.

I am convinced that it has something to do with the contruction of the server control - can you see anything there that I am lacking? I have done a silly amount of research on this, but couldn't find anything. the difficulty of not knowing what to look for doesn't help.

I tried rebuilding the entire DataList fresh with no clutter aside from the embedded server control - no luck.

Ben

Well, your issue maybe databinding. Here is a site I found on databound controls. You have to dig down through it. Maybe it will help you: http://www.codeproject.com/books/ASPNETCookbook.asp. It maybe how you retain the data in private variables; that may not be sufficient.

HTH, Brian

YES!

thank you, brian. The section in the article on adding viewstate support did the trick.

In the control, I needed to change the Property ID to this:

public int ProductID
{
    get
    {
    if(ViewState["productID"].ToString() !=null)
       return Convert.ToInt32(ViewState["productID"]);
    else
       return -1;

    }
    set
    {
    ViewState["productID"] = value;
    }
}