Adding columns dynamically to data grid

[Roger Frei]

Hello ng,

I have a datagrid that is bound to a datasource. That works good so far. Now
I want to add another column to my grid dynamically. That also works good
until the first postback. The column is still there but for some reason its
content is empty. I added the code underneath this post. The problem is that
the delegate CreateCellTempl ate is not called anymore. But why? I can't
understand.. :-( Viewstate is enabled for the grid.

Code
(The grid is an infragistics one. however, i think that has no impact in
that case.)

protected void Page_Load(objec t sender, EventArgs e) {

if (!Page.IsPostBa ck) {

// add column dynamically to grid
TemplatedColumn col = new TemplatedColumn (true);

col.CellTemplat e = new CompiledTemplat eBuilder(new
BuildTemplateMe thod(CreateCell Template));
myGrid.Columns. Insert(1, col);
}
}

private void CreateCellTempl ate(Control container) {

CellItem currentItem = (CellItem) container;

// cast it into my business object
InvoiceEntity dataItem = (InvoiceEntity) currentItem.Dat aItem;

CheckBox chkBox = new CheckBox();
chkBox.ID = "baseList." + dataItem.Id;
container.Contr ols.Add(chkBox) ;
}
Thanks in advance for your help!

Regards Roger

[Eliyahu Goldin]

You need to recreate dynamically added controls on every postback,
preferably in the PreInit event.

--
Eliyahu Goldin,
Software Developer & Consultant
Microsoft MVP [ASP.NET]
http://msmvps.com/blogs/egoldin
"Roger Frei" <sp**@hotmail.c omwrote in message
news:Oi******** ******@TK2MSFTN GP03.phx.gbl...

Hello ng,

I have a datagrid that is bound to a datasource. That works good so far.

Now

I want to add another column to my grid dynamically. That also works good
until the first postback. The column is still there but for some reason

its

content is empty. I added the code underneath this post. The problem is

that

the delegate CreateCellTempl ate is not called anymore. But why? I can't
understand.. :-( Viewstate is enabled for the grid.

Code
(The grid is an infragistics one. however, i think that has no impact in
that case.)

protected void Page_Load(objec t sender, EventArgs e) {

if (!Page.IsPostBa ck) {

// add column dynamically to grid
TemplatedColumn col = new TemplatedColumn (true);

col.CellTemplat e = new CompiledTemplat eBuilder(new
BuildTemplateMe thod(CreateCell Template));
myGrid.Columns. Insert(1, col);
}
}

private void CreateCellTempl ate(Control container) {

CellItem currentItem = (CellItem) container;

// cast it into my business object
InvoiceEntity dataItem = (InvoiceEntity) currentItem.Dat aItem;

CheckBox chkBox = new CheckBox();
chkBox.ID = "baseList." + dataItem.Id;
container.Contr ols.Add(chkBox) ;
}
Thanks in advance for your help!

Regards Roger

[Roger Frei]

Hi! Thanks a lot for your answer. I tried your suggestion. Firstly, I put
the code in the PreInit event. The problem there is that the grid is null at
this time.. :-( Then I tried it with the PreLoad event. Same result as
before when the code was in the Load method. :-(

It has something to do with the "CreateCellTemp ate" method. It is only
called if (isPostBack == false). It doesn't matter if I recreate the column
after every potsback or not. This method is called just once! Is this
somehow related with the databinding of the grid? Any ideas? :-)


"Eliyahu Goldin" <RE************ **************@ mMvVpPsS.orgsch rieb im
Newsbeitrag news:O1******** ******@TK2MSFTN GP02.phx.gbl...

You need to recreate dynamically added controls on every postback,
preferably in the PreInit event.

--
Eliyahu Goldin,
Software Developer & Consultant
Microsoft MVP [ASP.NET]
http://msmvps.com/blogs/egoldin
"Roger Frei" <sp**@hotmail.c omwrote in message
news:Oi******** ******@TK2MSFTN GP03.phx.gbl...

>Hello ng,

I have a datagrid that is bound to a datasource. That works good so far.

Now

>I want to add another column to my grid dynamically. That also works good
until the first postback. The column is still there but for some reason

its

>content is empty. I added the code underneath this post. The problem is

that

>the delegate CreateCellTempl ate is not called anymore. But why? I can't
understand.. :-( Viewstate is enabled for the grid.

Code
(The grid is an infragistics one. however, i think that has no impact in
that case.)

protected void Page_Load(objec t sender, EventArgs e) {

if (!Page.IsPostBa ck) {

// add column dynamically to grid
TemplatedColumn col = new TemplatedColumn (true);

col.CellTemplat e = new CompiledTemplat eBuilder(new
BuildTemplateM ethod(CreateCel lTemplate));
myGrid.Columns. Insert(1, col);
}
}

private void CreateCellTempl ate(Control container) {

CellItem currentItem = (CellItem) container;

// cast it into my business object
InvoiceEntity dataItem = (InvoiceEntity) currentItem.Dat aItem;

CheckBox chkBox = new CheckBox();
chkBox.ID = "baseList." + dataItem.Id;
container.Contr ols.Add(chkBox) ;
}
Thanks in advance for your help!

Regards Roger