Refresh Problem with DataGrid RowDetails

Refresh Problem with DataGrid RowDetails by ketelsb

Closed

as By Design Help for as By Design

Type:	Bug
ID:	612781
Opened:	10/12/2010 2:53:59 AM
Access Restriction:	Public

Workaround(s)

view

User(s) can reproduce this bug

http://forums.silverlight.net/forums/t/204721.aspx

I have a datagrid with rowdetails, but the data in the rowdetails is calculated.

When I select an item, I calculate the data that needs to be shown and update the Binding List of the DataGrid.

The rowdetails are not shown immediately. But when you scroll a little, they magically appear.

I fear this is a bug in the refresh of the RowDetails.

Details (expand)

Silverlight 4

Create a DataGrid with RowDetails and Bind data after the DataGrid Binding was completed.

Example: On the SelectedItem Changed Binding, alter the Binding Collection.
See attached application.

English

Windows 7

Dutch (Belgian)

The RowDetails are not immediately shown. When you scroll a little, the are suddenly shown.

The Rowdetails appear when the Binding source has been changed.

File Name	Submitted By	Submitted On	File Size
DataGridRowDetails.zip	ketelsb	10/12/2010	1.78 MB
DataGridRowDetails.zip	ketelsb	10/12/2010	1.78 MB

Hi,

The issue is the BookListItem class does not raise PropertyChanged for when the BookDetails changes. As a result, the TextBlock in the RowDetails is empty so it has 0 Height, and it appears that the RowDetails is not working. If the BookListItem implements INotifyPropertyChanged and raises PropertyChanged for BookDetails, you will see the issue go away:

    public class BookListItem : INotifyPropertyChanged
    {
        public event PropertyChangedEventHandler PropertyChanged;
        private string _bookdetails;

        public BookListItem(Book book)
        {
            Book = book;
        }

        public Book Book { get; set; }

        public string BookDetails
        {
            get
            {
                return _bookdetails;
            }
            set
            {
                if (_bookdetails != value)
                {
                    _bookdetails = value;
                    RaisePropertyChanged("BookDetails");
                }
            }
        }

        private void RaisePropertyChanged(string propertyName)
        {
            if (this.PropertyChanged != null)
            {
                this.PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
            }
        }
    }