GridViewExpression and nested data

[Rod]

I have some hierarchical data where my Primary ItemSource is a List<foo>   where foo contains a property List<MonthType> Months

In my gridView  I can do the following and it displays the sub List<Months> amount information in columns

<telerik:GridViewDataColumn Header="Account Title" DataMemberBinding="{Binding AccountTitle}" />
<telerik:GridViewDataColumn Header="Jan" DataMemberBinding="{Binding Months[0].Amount}" />

...

But this does not work

<telerik:GridViewExpressionColumn Header="Total2"  UniqueName="TotalValue2" DataFormatString="{}{0:C}" Expression="Months[0].Amount + ... + Months[11].Amount" />

If I put in a simple test - this works (Where RowID is a valid in in my data Object).

<telerik:GridViewExpressionColumn Header="Total" UniqueName="TotalValue" DataFormatString="{}{0:C}" Expression="RowID * 2" />

Any ideas on how to get this simple expressionColumn to work?

 

 

 

 

[Dimitrina]

Hi,

I am afraid ExpressionColumn is not going to calculate the values of such nested property. This is not supported.

Regards,
Didie
Telerik

 

 

[Rod]

That's odd, considering you are handling data binding at the nested level. 

Is there any other way (short of creating an additional property that adds everything together) to accomplish this?

Rod

[Dimitrina]

Hello,

The Expression engine is working differently than the DataMemberBinding.. 
Basically you can access simple nested properties, but not an item from a collection with indexer.
This is supported:

<telerik:GridViewExpressionColumn Expression="CustomO.Number"  Header="Stadium" />

Nevertheless, I found a workaround to be able to access the item you are interested in. You can do so with the ElementAt(index) function.
For example:

<telerik:GridViewExpressionColumn Expression="Players.ElementAt(0).Number" Header="Stadium" />

This seems to be a bug at our end and we will investigate it further.

Regards,
Didie
Telerik

 

 

[Rod]

Thanks for investigating it further.

Rod