public override object GetAt(int index)
{
object retval = null;
GroupGeneratorNode parentGroup = this.Parent as GroupGeneratorNode;
if ((parentGroup != null) && (parentGroup.IsExpanded == false))
{
retval = this.ComputeCollapsedGetAt(index);
}
else
{
retval = base.GetAt(index);
}
if (parentGroup != null)
{
retval = new GroupHeaderFooterItem(parentGroup.CollectionViewGroup, retval);
}
return(retval);
}
void IDataGridContextVisitor.Visit(DataGridContext sourceContext, GroupHeaderFooterItem groupHeaderFooter, ref bool stopVisit)
{
switch (m_status)
{
case SaveRestoreStateVisitorStatus.Saving:
{
this.SavingVisit(sourceContext, groupHeaderFooter);
break;
}
case SaveRestoreStateVisitorStatus.Restoring:
{
this.RestoringVisit(sourceContext, groupHeaderFooter);
break;
}
default:
{
throw new InvalidOperationException("An attempt was made to visit using a method other than the SaveRestoreStateVisitor's Save and Restore methods.");
}
}
}
public override int IndexOf(object item)
{
int retval = -1;
if (item != null)
{
GroupGeneratorNode parentGroup = this.Parent as GroupGeneratorNode;
//if the node is the child of a GroupGeneratorNode (then its a GroupHeader or GroupFooter).
if (parentGroup != null)
{
//Debug.Assert( ( item.GetType() == typeof( GroupHeaderFooterItem ) ), "item must be a GroupHeaderFooterItem for HeadersFootersGeneratorNode whose parent is a GroupGeneratorNode" );
if (item.GetType() == typeof(GroupHeaderFooterItem))
{
//only process further is the ParentGroup match the requested group.
GroupHeaderFooterItem ghf = ( GroupHeaderFooterItem )item;
if (ghf.Group == parentGroup.CollectionViewGroup)
{
retval = this.IndexOfHelper(parentGroup, ghf.Template);
}
}
else
{
retval = this.IndexOfHelper(parentGroup, item);
}
}
else
{
//if there is no parent group (or no parent at all), then process the item directly!
retval = this.IndexOfHelper(parentGroup, item);
}
}
return(retval);
}
public void Visit( DataGridContext sourceContext, GroupHeaderFooterItem groupHeaderFooter, ref bool stopVisit )
{
throw new NotSupportedException( "The RangeSelectionVisitor is only capable of handling data items block." );
}
protected virtual void RestoringVisit(DataGridContext sourceContext, GroupHeaderFooterItem groupHeaderFooter)
{
throw new NotImplementedException();
}
public void Visit( DataGridContext sourceContext, GroupHeaderFooterItem groupHeaderFooter, ref bool stopVisit )
{
throw new NotSupportedException();
}
public static bool Equals( GroupHeaderFooterItem item1, GroupHeaderFooterItem item2 )
{
return ( ( item1.m_template == item2.m_template ) && ( item1.Group == item2.Group ) );
}
public void Visit(DataGridContext sourceContext, GroupHeaderFooterItem groupHeaderFooter, ref bool stopVisit)
{
throw new NotSupportedException("The RangeSelectionVisitor is only capable of handling data items block.");
}
public bool Equals(GroupHeaderFooterItem item)
{
return(GroupHeaderFooterItem.Equals(this, item));
}
void IDataGridContextVisitor.Visit( DataGridContext sourceContext, GroupHeaderFooterItem groupHeaderFooter, ref bool stopVisit )
{
switch( m_status )
{
case SaveRestoreStateVisitorStatus.Saving:
{
this.SavingVisit( sourceContext, groupHeaderFooter );
break;
}
case SaveRestoreStateVisitorStatus.Restoring:
{
this.RestoringVisit( sourceContext, groupHeaderFooter );
break;
}
default:
{
throw new InvalidOperationException( "An attempt was made to visit using a method other than the SaveRestoreStateVisitor's Save and Restore methods." );
}
}
}
protected virtual void RestoringVisit( DataGridContext sourceContext, GroupHeaderFooterItem groupHeaderFooter )
{
throw new NotImplementedException();
}
public void Visit(DataGridContext sourceContext, GroupHeaderFooterItem groupHeaderFooter, ref bool stopVisit)
{
throw new NotSupportedException();
}
public bool Equals( GroupHeaderFooterItem item )
{
return GroupHeaderFooterItem.Equals( this, item );
}
//This method cannot be used for groups.
//This method will search for items independently of the Expanded/Collpased status of GroupGeneratorNodes
public bool Contains(object item)
{
bool skipCollectionGeneratorNodeCheck = false;
do
{
HeadersFootersGeneratorNode headersFootersNode = m_currentNode as HeadersFootersGeneratorNode;
skipCollectionGeneratorNodeCheck = false;
//If the node is a HeadersFootersGeneratorNode, do some specific handling.
if (headersFootersNode != null)
{
//If the item passed to the function is a GroupHeaderFooterItem, then its because we are looking for a GroupHeader/Footer
if (item.GetType() == typeof(GroupHeaderFooterItem))
{
GroupHeaderFooterItem groupHeaderFooterItem = ( GroupHeaderFooterItem )item;
//Determine the parent node/collectionViewGroup
GroupGeneratorNode parentGroup = headersFootersNode.Parent as GroupGeneratorNode;
if (parentGroup != null)
{
if (groupHeaderFooterItem.Group == parentGroup.CollectionViewGroup)
{
if (headersFootersNode.Items.Contains(groupHeaderFooterItem.Template))
{
return(true);
}
}
}
//If there is no parent node, then its because the current HeadersFootersGeneratorNode is not a GroupHeaders/Footers node (FixedHeaders/Fotoers or Headers/Footers).
skipCollectionGeneratorNodeCheck = true; //force skip CollectionGeneratorNode verification, this is to limit amount of job done by loop body.
}
//If the item passed is not a GroupHeaderFooterItem, not need to do specific processing, reverting to "Common" algo.
}
if (!skipCollectionGeneratorNodeCheck)
{
CollectionGeneratorNode collectionNode = m_currentNode as CollectionGeneratorNode;
if (collectionNode != null)
{
// When dealing with a DataView, the DataView's IList's Contains implementation will return false
// for a dataRowView which is in edition and was modified even though it is really part of the collection.
// Therefore, we must use a for loop of Object.Equals method calls.
System.Data.DataRowView dataRowViewItem = item as System.Data.DataRowView;
if (dataRowViewItem != null)
{
IList items = collectionNode.Items;
int itemsCount = items.Count;
System.Data.DataRow itemDataRow = dataRowViewItem.Row;
for (int i = 0; i < itemsCount; i++)
{
System.Data.DataRowView currentDataRowView = items[i] as System.Data.DataRowView;
if ((currentDataRowView != null) && (itemDataRow == currentDataRowView.Row))
{
return(true);
}
}
}
else
{
//Since the GetAt() methods can be overriden to compensate for the Expand/Collapse status of Groups
// AND the details features, accessing the collection directly prevent pre-processing of the content of the collection node.
if (collectionNode.Items.Contains(item))
{
//if the item is from a detail, then I don't want to "use" it!!!
return(true);
}
}
}
}
//if we reach this point, it's because the item we are looking
//for is not in this node... Try to access the child
//Note: Since I want to search independently of the Expand/Collapse status,
//pass false to the method to systematically visit childs.
if (this.MoveToChild(false))
{
continue;
}
//if we reach this point, it's because we have no child...
if (this.MoveToNext())
{
continue;
}
//final try, try "advancing" to the next item.
if (this.MoveToFollowing())
{
continue;
}
//up to this, we are in an endpoint, we failed.
break;
} while(true);
return(false);
}
public static bool Equals(GroupHeaderFooterItem item1, GroupHeaderFooterItem item2)
{
return((item1.m_template == item2.m_template) && (item1.Group == item2.Group));
}
public void Visit(DataGridContext sourceContext, GroupHeaderFooterItem groupHeaderFooter, ref bool stopVisit)
{
throw new NotSupportedException("Only DataGridContexts can be visited by this visitor.");
}
public static bool operator !=(GroupHeaderFooterItem item1, GroupHeaderFooterItem item2)
{
return(!GroupHeaderFooterItem.Equals(item1, item2));
}
public void Visit( DataGridContext sourceContext, GroupHeaderFooterItem groupHeaderFooter, ref bool stopVisit )
{
throw new NotSupportedException( "Only DataGridContexts can be visited by this visitor." );
}
public override object GetAt( int index )
{
object retval = null;
GroupGeneratorNode parentGroup = this.Parent as GroupGeneratorNode;
if( ( parentGroup != null ) && ( parentGroup.IsExpanded == false ) )
{
retval = this.ComputeCollapsedGetAt( index );
}
else
{
retval = base.GetAt( index );
}
if( parentGroup != null )
{
retval = new GroupHeaderFooterItem( parentGroup.CollectionViewGroup, retval );
}
return retval;
}