/// <summary>
/// Synchronizes the sort descriptions collection to the sort descriptors collection.
/// </summary>
/// <param name="descriptor">The descriptor that changed</param>
/// <param name="e">The property change event</param>
private void HandleSortDescriptorChanged(SortDescriptor descriptor, PropertyChangedEventArgs e)
{
this._ignoreChanges = true;
try
{
// We have to reset when the collections were not equal before the change
if (this._sourceCollection.Count != this._descriptionCollection.Count)
{
SortCollectionManager.ResetToSortDescriptors(this._descriptionCollection, this._sourceCollection);
}
else
{
int index = this._sourceCollection.IndexOf(descriptor);
SortDescription? description = SortCollectionManager.GetDescriptionFromDescriptor(descriptor);
if (!description.HasValue)
{
this._descriptionCollection.RemoveAt(index);
}
else
{
this._descriptionCollection[index] = description.Value;
}
}
}
finally
{
this._ignoreChanges = false;
}
}
/// <summary>
/// Determines whether the <paramref name="sortDescription"/> and <paramref name="sortDescriptor"/> are equivalent.
/// </summary>
/// <param name="sortDescription">The description to compare</param>
/// <param name="sortDescriptor">The descriptor to compare</param>
/// <returns><c>true</c> if the two are equivalent</returns>
private static bool AreEquivalent(SortDescription sortDescription, SortDescriptor sortDescriptor)
{
Debug.Assert((sortDescription != null) && (sortDescriptor != null), "Both should be non-null.");
return (sortDescription.Direction == sortDescriptor.Direction) &&
(sortDescription.PropertyName == sortDescriptor.PropertyPath);
}
/// <summary>
/// Returns a <see cref="SortDescription"/> equivalent to the specified descriptor.
/// </summary>
/// <param name="sortDescriptor">The descriptor to get a description from</param>
/// <returns>A <see cref="SortDescription"/> equivalent to the specified descriptor</returns>
private static SortDescription? GetDescriptionFromDescriptor(SortDescriptor sortDescriptor)
{
if (string.IsNullOrEmpty(sortDescriptor.PropertyPath))
{
return null;
}
return new SortDescription(sortDescriptor.PropertyPath, sortDescriptor.Direction);
}