GREAT. It worked after I did code changes as you suggested. Thank you so much for your detailed explanation on this issue.

Thanks again

Hi,

There are two issues here. The first one is one that you sorta ran into but your solution isn't quite right. Your idea of checking for null in the txt_TextChanged event is on the right track, but it's too late.

When you click on the cell in the Template AddRow, the UltraControlContainerEditor tries to apply the value of the field in the grid to the AddressControl.Address property. This is failing, because the value in the field is DBNull.Value and the Address property is of type Address, so it cannot accept DBNull.

So rather than checking for null in TextChanged, one thing you could do is initialize the default value of the grid cell to something that the Address control can handle:

        private void ultraGrid1_InitializeTemplateAddRow(object sender, Infragistics.Win.UltraWinGrid.InitializeTemplateAddRowEventArgs e)
        {
            e.TemplateAddRow.Cells["Address"].Value = new Address("Street1", "City1", "CA", "12345");
        }

It would probably be a good idea for it to try using null instead of DBNull in a case like this. We already do that if you use a Nullable type, but apparently not when you use a reference type, even though it can accept null.

The second issue is that the AddressControl is not sending any notification when the Address is changed. This class does not implement INotifyPropertyChanged and it does not fire an AddressChanged event. So the grid has no way of knowing that the field is dirty and doesn't create a new TemplateAddRow.

This is sort've odd, because if this field was anything other than a reference type, the sample would not work when you edit a regular row. The grid actually has no idea that the data is dirty when you edit this field. The thing is - it doesn't need to know in the case of an existing row, because the value of the cell does not actually change. It's only properties on the object in the field that change. So that's probably why no one noticed it until now.

The Address class implements INotifyPropertyChanged, but the AddressControl does not. The AddressControl is already hooking the PropertyChanged event on the Address to update it's UI. So to fix this, you have to implement INotifyPropertyChanged on the AddressControl and fire PropertyChanged from the address_PropertyChanged method, and also any time the Address property is set.

Hi Mike,

Thanks for your quick reply. After I did service release update, the problem was still there. To let us working on the same page, I used the ControlContainerEditor sample solution to do this test. Here are what I did:
1) Install service release update for 2010 v2
2) Open C# sample solution for ControlContainerEditor
3) Under Folder "Same Editor and Render Control", open AddressControl.cs and add codes in the begin of the txt_TextChanged method to avoid error:
                if (this.address == null)
                      this.address = new Address("Street1", "City1", "CA", "12345");
4) Open "SameRenderandEditForm" form and change the ultragrid1.displaylayout.bands(0).override.AllowAddNew to be "TemplateOnTop"
5) Run the app
6) You will see the TempleAddRow can't be inserted and when you click a existing row, the TemplateAddRow will be filled with the content of the selected row.

These all I have done and hope it can give you some clues what the problem is.

Thanks,

Actually I already implemented INotifyPropertyChanged interface for the class which is bound to the editor and rendering control. For existing rows the grid can update properly but it can't update when the row is the TemplateAddNew row. I will try to raise ValueChanged event to see if it works and check my codes to see if my codes have bugs.

Thanks,