C# how to bind a datagrid t observableCollection of classes with observable collections using code behind

Question

I have a datagrid which has to be associated to an observable collection of the following class:

public class CfgCounters
{
    public int valuePresent { get; set; }
    public string Name { get; set; }
    public ObservableCollection<DateTime> obcDatetime { get; set; }
    public ObservableCollection<string> obcLastExecutedPP { get; set; }
    public ObservableCollection<int> obcNumDimsOK { get; set; }
}

I have therefore

ObservableCollection<CfgCounters> obcCounters = new ObservableCollection<CfgCounters>();

which I fill with instances and then associate to the dtg with dtg.ItemsSource = obcCounters;

the result is

which obviously is not showing the obcs in any way. So the question is: how can I in code behind show (in any way would do) those observable collections using code behind only ? Thanks

Answer 1

You should transform each CfgCounters object into an item with only scalar properties, eg:

ObservableCollection<CfgCounters> obcCounters = new ObservableCollection<CfgCounters>();
...
dtg.ItemsSource = obcCounters.Select(x => new
{
    x.valuePresent,
    x.Name,
    obcDatetime = string.Join(",", x.obcDatetime.Select(y => y.ToString("yyyy-MM-dd"))),
    obcLastExecutedPP = string.Join(",", x.obcLastExecutedPP),
    obcNumDimsOK = string.Join(",", x.obcNumDimsOK)
}).ToArray();

Answer 2

Your data is hierarchical and your view is not. You maybe looking for:

1. TreeView to display hierarchical data as you have.

2. Or you can flatten the data and use this as the source of the datagrid. The code examples show a view model inherited from the data model but a conversion in code behind to a new type would also be possible.

3. Datagrid can also group lists. But this doesn't fit here, see 2.

---

When the csv doesn't change at run time:

public class CfgCountersViewModel : CfgCounters
{

    public string obcDatetimeCsv => String.Join(",", obcDatetime);
    ...
}

Or when the childs of CfgCounters changes during run time, something more complex like:

public class CfgCountersViewModel : CfgCounters, INotifyPropertyChanged
{
    public CfgCountersViewModel() 
    {
         // UpdateObcDatetimeCsv when obcDatetime changes
         obcDatetime.OnCollectionChanged += (sender, args) => 
         {
              obcDatetimeCsv = String.Join(",", obcDatetime);
         }
    }
    ...
}