I have a dynamically created GirdView based on value of a DropDownList.
I use the ITemplate interface to generate the fields:
public class CreateItemTemplateOrder : ITemplate
{
ImageButton imgbtn_up;
ImageButton imgbtn_down;
string s_imgbtn_up_name;
string s_imgbtn_up_ImageUrl;
string s_imgbtn_up_CommandName;
string s_imgbtn_up_CommandArgument;
public CreateItemTemplateOrder(string imgbtn_up_name, string imgbtn_up_ImageUrl, string imgbtn_up_CommandName, string imgbtn_up_CommandArgument)
{
this.s_imgbtn_up_name = imgbtn_up_name;
this.s_imgbtn_up_ImageUrl = imgbtn_up_ImageUrl;
this.s_imgbtn_up_CommandName = imgbtn_up_CommandName;
this.s_imgbtn_up_CommandArgument = imgbtn_up_CommandArgument;
}
public void InstantiateIn(Control objContainer)
{
imgbtn_up = new ImageButton();
imgbtn_up.DataBinding += new EventHandler(imgbtn_up_DataBinding);
objContainer.Controls.Add(imgbtn_up);
}
private void imgbtn_up_DataBinding(object sender, EventArgs e)
{
ImageButton imgbtn_up = (ImageButton)sender;
imgbtn_up.ID = s_imgbtn_up_name;
imgbtn_up.ImageUrl = s_imgbtn_up_ImageUrl;
imgbtn_up.CommandName = s_imgbtn_up_CommandName;
imgbtn_up.CommandArgument = s_imgbtn_up_CommandArgument;
imgbtn_up.CausesValidation = false;
}
}
Now I want to fire RowCommand From this dynamically generated column with command argument and command name bounded to this ImageButton
the code to get this working is:
Protected void inizializza_gw_tipi(){
TemplateField order_col = new TemplateField;
order_col.ItemTemplate = new CreateItemTemplateOrdine("imgbtn_up", "~/imgs/Up.gif", "minus", "order");
order_col.HeaderText = "order";
order_col.SortExpression = "order";
gw_tipi.Columns.Add(order_col);
}
All this code works fine but doesn’t fire RowCommand from GridView when clicked on the ImageButton
EDIT:
I call the procedure in SelectedIndexChanged event of a DropDownList
ddl_tipi_SelectedIndexChanged(Object sender , System.EventArgs e)
{
inizializza_gw_tipi();
gw_tipi.DataBind();
}
Protected Sub inizializza_gw_tipi()
Using cn As New SqlConnection(shared_foos.connectionString)
Using cmd As New SqlCommand("SELECT nome_tabella, nome_campo_id, nome_campo_nome, nome_campo_descrizione, has_order FROM maschere_tipi WHERE id = @id", cn)
cmd.Parameters.AddWithValue("id", IIf(Session("sel_val") Is Nothing, "", Session("sel_val")))
cn.Open()
Dim rdr As SqlDataReader = cmd.ExecuteReader
rdr.Read()
If rdr.HasRows Then
Dim b_crea_controllo As Boolean = True
'controllo se mettere o no la colonna ordine
If rdr("has_order") = True Then
'controllo che la colonna non sia già stata inserita,
'se è già stata inserita la rimuovo e la ricreo
For i As Integer = 0 To gw_tipi.Columns.Count - 1
If gw_tipi.Columns(i).HeaderText = "ordine" Then
'gw_tipi.Columns.Remove(gw_tipi.Columns(i))
b_crea_controllo = False
End If
Next
If b_crea_controllo = True Then
Dim ordine_col As New TemplateField()
ordine_col.ItemTemplate = New CreateItemTemplateOrdine("lbl_ordine", "ordine", "imgbtn_up", "~/imgs/Up.gif", "meno", "ordine", "imgbtn_down", "~/imgs/Down.gif", "piu", "ordine", AddressOf ImageCommand)
ordine_col.HeaderText = "ordine"
ordine_col.SortExpression = rdr("nome_campo_nome")
gw_tipi.Columns.Add(ordine_col)
End If
End If
b_crea_controllo = True
For i As Integer = 0 To gw_tipi.Columns.Count - 1
If gw_tipi.Columns(i).HeaderText = rdr("nome_campo_nome") Then
b_crea_controllo = False
End If
Next
If b_crea_controllo = True Then
Dim nome_col As New TemplateField()
nome_col.ItemTemplate = New CreateItemTemplateLabel("lbl_nome", rdr("nome_campo_nome"))
nome_col.HeaderText = rdr("nome_campo_nome")
nome_col.SortExpression = rdr("nome_campo_nome")
gw_tipi.Columns.Add(nome_col)
End If
b_crea_controllo = True
For i As Integer = 0 To gw_tipi.Columns.Count - 1
If gw_tipi.Columns(i).HeaderText = rdr("nome_campo_descrizione") Then
b_crea_controllo = False
End If
Next
If b_crea_controllo = True Then
Dim descrizione_col As New TemplateField()
descrizione_col.ItemTemplate = New CreateItemTemplateLabel("lbl_descrizione", rdr("nome_campo_descrizione"))
descrizione_col.HeaderText = rdr("nome_campo_descrizione")
descrizione_col.SortExpression = rdr("nome_campo_descrizione")
gw_tipi.Columns.Add(descrizione_col)
End If
Dim str_order_by As String = " ORDER BY "
Dim str_ordine As String = ""
If rdr("has_order") = True Then
str_ordine = ", ordine "
str_order_by &= "ordine"
Else
str_order_by &= rdr("nome_campo_nome")
End If
Dim sqlds_tipi As New SqlDataSource(shared_foos.connectionString, "SELECT " & rdr("nome_campo_id") & ", " & rdr("nome_campo_nome") & ", " & rdr("nome_campo_descrizione") & str_ordine & " FROM " & rdr("nome_tabella") & str_order_by)
gw_tipi.DataSource = sqlds_tipi
End If
End Using
End Using
End Sub
I took your code as is and tested. there is no errors on this code. Also the row command is triggered properly. I presume the problem is with eventbinding of the dynamic gridview you created.
For the row command to be triggered the gridview has to be created on every postback. and the event should be bound.
The Code you provided is not exactly what i needed. It doesn’t have the initialization of the grid view.
The following should give you some insight.
The server doesnt keep track of dynamically created controls. So when the post back occurs the gridview control does not exist. and thus no event can be triggered.