Question

this seemed simple at first but I can’t get it to work.

I have the following scenario:

        <asp:ListView ID="CommentsListView" runat="server">
            <LayoutTemplate>
                    <asp:PlaceHolder ID="itemPlaceholder" runat="server" />
            </LayoutTemplate>
            <ItemTemplate>
                <UC:Comment runat="server" CommentItem="<%# CurrentComment %>" />
                <br />
            </ItemTemplate>
        </asp:ListView>
        <asp:TextBox ID="NewComment" runat="server" />
        <asp:ImageButton ImageUrl="/images/ball.png" runat="server"
                      OnClick="SubmitComment" />

Code:

    protected void Page_Load(object sender, EventArgs e)
    {
         RenderListView();
    }

    protected void RenderListView()
    {
        CommentsListView.DataSource = //Get the data source objects
        CommentsListView.DataBind();
    }

    protected CommentObject CurrentComment
    {
        get { return (CommentObject)Page.GetDataItem(); }
    }

    protected void SubmitComment(object sender, ImageClickEventArgs e)
    {   
        //code to submit comment

        RenderListView();
    }

basically, when I submit a comment, I want to see it in the ListView, but I don’t. “MyControl” gets a null comment in the post-back, for all of the items (not just the new one).

Only after I refresh the page, I can see the new comment that I’v submitted. I can’t however refresh the page every submit because this code is inside an UpdatePanel (the issue occurs without the UpdatePanel as well).

Any idea how to solve this?

Answer 1

I finally solved it, if anyone else may encounter this –

The solution was to avoid “<%#” and instead use the ItemDataBound event:

 <asp:ListView ID="Comments" runat="server" 
OnItemDataBound="CommentsItemDataBound">

and the method itself:

protected void CommentsItemDataBound(object sender, ListViewItemEventArgs e)
{
    var commentItem = (Comment)(((ListViewDataItem)e.Item).DataItem);

    var commentControl = (Comment)e.Item.FindControl("CommentControl");
    commentControl.CommentItem = commentItem;
}

This way, the binding of each control works as expected.