public override void MoveMasterRecord(TMasterDetailLink[] masterDetailLinks, TSplitLink splitLink)
{
//Here we need to modify FilteredData to contain only those records on FilteredData that are visible on this state.
//If we created indexes on this method constructor's, this can be done fast.
//on this example, as always, we will use a very slow method. The idea of this demo is not to demostrate how to do efficient code
// (you probably have efficient methods on the bussines objects you are wrapping), but how to override the methods.
if (FilteredData == null)
{
return; //this dataset is not on master-detail relationship and does not have any split relationship either.
}
FilteredData.Clear();
int[] ChildColumn = new int[masterDetailLinks.Length];
for (int i = 0; i < masterDetailLinks.Length; i++)
{
ChildColumn[i] = TableData.GetColumn(masterDetailLinks[i].ChildFieldName);
}
int SplitPos = 0;
int StartRow = 0;
if (splitLink != null)
{
StartRow = splitLink.SplitCount * splitLink.ParentDataSource.Position;
}
for (int r = 0; r < SortedData.Length; r++)
{
object[] Row = SortedData[r];
bool RowApplies = true;
for (int i = 0; i < masterDetailLinks.Length; i++)
{
object key = masterDetailLinks[i].ParentDataSource.GetValue(masterDetailLinks[i].ParentField);
if (Convert.ToString(Row[ChildColumn[i]]) != Convert.ToString(key))
{
RowApplies = false;
break;
}
}
if (!RowApplies)
{
continue; //the row does not fit this master detail relationship.
}
SplitPos++;
if (SplitPos <= StartRow)
{
continue; //we are not filling the correct split slot.
}
FilteredData.Add(Row);
if (splitLink != null && FilteredData.Count >= splitLink.SplitCount)
{
return;
}
}
}
public override VirtualDataTableState CreateState(string sort, TMasterDetailLink[] masterDetailLinks, TSplitLink splitLink)
{
return(new SimpleVirtualArrayDataSourceState(this));
}
public ComplexVirtualArrayDataSourceState(ComplexVirtualArrayDataSource aTableData, string sort, TMasterDetailLink[] masterDetailLinks, TSplitLink splitLink)
: base(aTableData)
{
if (sort == null || sort.Trim().Length == 0)
{
SortedData = aTableData.Data; //no need to clone, this is invariant.
}
else
{
SortedData = (object[][])aTableData.Data.Clone();
int sortcolumn = aTableData.GetColumn(sort);
if (sortcolumn < 0)
{
throw new Exception("Can not find column \"" + sort + "\" in dataset \"" + TableName);
}
Array.Sort(SortedData, new ArrayComparer(sortcolumn));
}
//here we should use the data in masterdetaillinks and splitlink to create indexes to make the FilteredrowCount and MoveMasterRecord methods faster.
//on this demo we are not going to do it.
if ((masterDetailLinks != null && masterDetailLinks.Length > 0) || splitLink != null)
{
FilteredData = new List <object[]>();
}
}