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GridViewCollectionChangingEventArgs ?

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GridView

This is a migrated thread and some comments may be shown as answers.

Thomas asked on 08 Dec 2011, 05:00 PM

Hello,

Trying to catch the 'SortChanging' event.

My first guess is that in GridViewCollectionChangingEventArgs
.NewItems, I'm going to fing the new 'SortDescriptor', and in GridViewCollectionChangingEventArgs
.OldItems

But I see that the behavior is different from what I exepected

Initial state: the gridview is not sorted.
Action : I click on the column titles.

1° Click on columne A : First time, the grid is not sorted, in NewItems, I find one 'new item' corresponding to what expected.
NewItems : A Ascending; [as expected]
OldItems : null; [as expected]
2° I click on the same column again
NewItems : A descending; [as expected]
OldItems : A descending; [not as expected : I expected A Ascending]
3° I click on another column
NewItems : A descending; [not as expected : I expected B something]
OldItems : A descending; [as expected]

(NewItems and OldItems are always = 1.)

Which means that I can when changing sort, I can not distinguinshed what exactly has changed from the EventArgs.

Or am I not doing this the right way ?

Thank you for your help.

And in case here the code I'm using to test it right now:

            object o;
            SortDescriptor newSortDescriptor, oldSortDescriptor;
            string newItemString, oldItemString;

            for (int i = 0; i < e.NewItems.Count; i++)
            {
                o = e.NewItems[i];
                if(o.GetType().Equals(typeof(SortDescriptor))) {
                    newSortDescriptor = (SortDescriptor)o;
                    newItemString = newSortDescriptor.PropertyName + ' ' + newSortDescriptor.Direction;
                }

            }

            for (int i = 0; i < e.OldItems.Count; i++)
            {
                o = e.OldItems[i];
                if (o.GetType().Equals(typeof(SortDescriptor)))
                {
                    oldSortDescriptor = (SortDescriptor)o;
                    oldItemString = oldSortDescriptor.PropertyName + ' ' + oldSortDescriptor.Direction;
                }
            }

5 Answers, 1 is accepted

answered on 25 Jan 2013, 04:15 PM

This issue still exists (I am using Q3 2012 SP1). The EventArgs members "OldItems" and "NewItems" sometimes do not have correct values.

What I wanted to achieve is to get a BindingSource updated when an user changes the sorting of a RadGridView on the same Form. Call it kind of "sorting synchronisation" (Direction and Property/ColumnName) between the two of them. This is what I use until the error is fixed... if so.

private void DataGrid_SortChanged(object sender, GridViewCollectionChangedEventArgs e)

{

    // ...



    SortDescriptor sortDescriptor;

if (e.OldItems != null && e.OldItems[0] as SortDescriptor != null)

{

sortDescriptor = (SortDescriptor) e.OldItems[0];

Debug.WriteLine("Using OldItem for Sorting: " + sortDescriptor.PropertyName + " " + sortDescriptor.Direction);

}

else

{

if (e.NewItems != null && e.NewItems[0] as SortDescriptor != null)

{

sortDescriptor = (SortDescriptor) e.NewItems[0];

Debug.WriteLine("Using NewItem for Sorting: " + sortDescriptor.PropertyName + " " + sortDescriptor.Direction);

}

    }



    if (sortDescriptor == null) return;



    var direction = (sortDescriptor.Direction == ListSortDirection.Ascending)

                    ? "ASC"

                    : "DESC";



    MyBindingSource.Sort = String.Concat(sortDescriptor.PropertyName, " ", direction);

}