/// <summary>
/// Handles adding an item into the collection, and applying sorting, filtering, grouping, paging.
/// </summary>
/// <param name="item">Item to insert in the collection</param>
/// <param name="index">Index to insert item into</param>
private void ProcessInsertToCollection(object item, int index)
{
// first check to see if it passes the filter
if (this.Filter == null || this.PassesFilter(item))
{
if (this.SortDescriptions.Count > 0)
{
// create the SortFieldComparer to use
SortFieldComparer sortFieldComparer = new SortFieldComparer(this.SortDescriptions);
// check if the item would be in sorted order if inserted into the specified index
// otherwise, calculate the correct sorted index
if (index < 0 || /* if item was not originally part of list */
(index > 0 && (sortFieldComparer.Compare(item, this.InternalItemAt(index - 1)) < 0)) || /* item has moved up in the list */
((index < this.InternalList.Count - 1) && (sortFieldComparer.Compare(item, this.InternalItemAt(index)) > 0))) /* item has moved down in the list */
{
index = sortFieldComparer.FindInsertIndex(item, this._internalList);
}
}
// make sure that the specified insert index is within the valid range
// otherwise, just add it to the end. the index can be set to an invalid
// value if the item was originally not in the collection, on a different
// page, or if it had been previously filtered out.
if (index < 0 || index > this._internalList.Count)
{
index = this._internalList.Count;
}
this._internalList.Insert(index, item);
}
}
private void ProcessInsertToCollection(object item, int index)
{
if ((this.Filter == null) || this.PassesFilter(item))
{
if (this.SortDescriptions.Count > 0)
{
SortFieldComparer comparer = new SortFieldComparer(this.SortDescriptions);
if (((index < 0) || ((index > 0) && (comparer.Compare(item, this.InternalItemAt(index - 1)) < 0))) || ((index < (this.InternalList.Count - 1)) && (comparer.Compare(item, this.InternalItemAt(index)) > 0)))
{
index = comparer.FindInsertIndex(item, this._internalList);
}
}
if ((index < 0) || (index > this._internalList.Count))
{
index = this._internalList.Count;
}
this._internalList.Insert(index, item);
}
}
