Cant find a Div inside of my child repeater - asp.net

Question

Im trying to change the Visible of my Div, but im not being able to find it. Its seems because its inside of another Repeater.
<asp:Repeater ID="uxPesquisaList" runat="server" OnItemDataBound="uxQuestList_ItemDataBound">
<ItemTemplate>
<tr>
<td>
<strong>
<%# DataBinder.Eval(Container.DataItem,"Descricao")%></strong>
</td>
</tr>
<%-- Listagem de Respostas --%>
<asp:Repeater ID="uxRespList" runat="server">
<ItemTemplate>
<tr>
<div id="uxRespostaText" visible="false" runat="server"> ***I want to display this Div***
<td>
<asp:TextBox ID="uxResposta" runat="server" Text='<%# DataBinder.Eval(Container.DataItem, "Descricao")%>' />
</td>
</div>
</tr>
</ItemTemplate>
</asp:Repeater>
</ItemTemplate>
</asp:Repeater>
My Code Behind
protected void uxQuestList_ItemDataBound(object sender, RepeaterItemEventArgs e)
{
if (e.Item.ItemType == ListItemType.Item || e.Item.ItemType == ListItemType.AlternatingItem)
{
Repeater rptRespostas = (Repeater)(e.Item.FindControl("uxRespList"));
QuestionarioPergunta pergunta = (QuestionarioPergunta)e.Item.DataItem;
System.Web.UI.HtmlControls.HtmlContainerControl uxRespostaText = (System.Web.UI.HtmlControls.HtmlContainerControl)e.Item.FindControl("uxRespostaText"); **I try this, but it always return NullExpection**
if (pergunta.TipoPergunta == "Dissertativa")
{
uxRespostaText.Visible = true;
}
rptRespostas.DataSource = ctx.QuestionarioRespostas.Where(x => x.PergId == pergunta.Id).ToList();
rptRespostas.DataBind();
}
}

Answer 1

You have to look for the TextBox in each item of the inner Repeater. You can set the ItemDataBound event handler of uxRespList in the markup:
<asp:Repeater ID="uxRespList" runat="server" OnItemDataBound="uxRespList_ItemDataBound">
In code-behind, you bind the data of that inner Repeater in the event handler of the outer Repeater (as you already do in your code):
protected void uxQuestList_ItemDataBound(object sender, RepeaterItemEventArgs e)
{
if (e.Item.ItemType == ListItemType.Item || e.Item.ItemType == ListItemType.AlternatingItem)
{
Repeater rptRespostas = e.Item.FindControl("uxRespList") as Repeater;
...
rptRespostas.DataSource = ...
rptRespostas.DataBind();
}
}
And you process each inner Repeater item after its data is bound:
protected void uxRespList_ItemDataBound(object sender, RepeaterItemEventArgs e)
{
if (e.Item.ItemType == ListItemType.Item || e.Item.ItemType == ListItemType.AlternatingItem)
{
TextBox uxRespostaText = e.Item.FindControl("uxRespostaText") as TextBox;
...
}
}