private void RecursiveSaveDataGridContextsState(DataGridContext dataGridContext)
{
var saveRestoreDataGridContextStateVisitor = new SaveRestoreDataGridContextStateVisitor(true, int.MaxValue, m_stopAtFirstCollapsedGroup);
saveRestoreDataGridContextStateVisitor.SaveState(dataGridContext as IDataGridContextVisitable);
m_dataGridContextsStateDictionary.Add(new WeakDataGridContextKey(dataGridContext), saveRestoreDataGridContextStateVisitor);
foreach (var subDataGridContext in dataGridContext.GetChildContextsCore())
{
this.RecursiveSaveDataGridContextsState(subDataGridContext);
}
}
private void RecursiveRestoreDataGridContextsState(DataGridContext dataGridContext)
{
var weakDataGridContextKey = new WeakDataGridContextKey(dataGridContext);
var saveRestoreDataGridContextStateVisitor = default(SaveRestoreDataGridContextStateVisitor);
if (m_dataGridContextsStateDictionary.TryGetValue(weakDataGridContextKey, out saveRestoreDataGridContextStateVisitor))
{
try
{
saveRestoreDataGridContextStateVisitor.RestoreState(dataGridContext as IDataGridContextVisitable);
}
finally
{
m_dataGridContextsStateDictionary.Remove(weakDataGridContextKey);
}
}
foreach (var subDataGridContext in dataGridContext.GetChildContextsCore())
{
this.RecursiveRestoreDataGridContextsState(subDataGridContext);
}
}
internal void ProcessVisit(
DataGridContext sourceContext,
int minIndex,
int maxIndex,
IDataGridContextVisitor visitor,
DataGridContextVisitorType visitorType,
bool visitDetails,
out bool visitWasStopped)
{
visitWasStopped = false;
// This is used only for DataGridContextVisitorType.ItemsBlock
var startSourceDataItemIndex = -1;
var endSourceDataItemIndex = -1;
if (minIndex < 0)
{
throw DataGridException.Create <ArgumentException>("The minimum index must be greater than or equal to zero.", sourceContext.DataGridControl, "minIndex");
}
if ((visitorType & DataGridContextVisitorType.DataGridContext) == DataGridContextVisitorType.DataGridContext)
{
visitor.Visit(sourceContext, ref visitWasStopped);
if (visitWasStopped)
{
return;
}
}
//Take a shortcut, if the visit is made only for contexts, and there is no child contexts
//return right away.
var containsDetails = false;
foreach (var childContext in sourceContext.GetChildContextsCore())
{
containsDetails = true;
break;
}
var processed = false;
var current = m_state;
while (true)
{
processed = false;
var itemCount = current.Node.ItemCount;
//If the whole current node is below the minIndex, jump over it.
if ((current.Index + (itemCount - 1)) < minIndex)
{
processed = true;
}
//when the index to visit exceeds the range defined, exit the loop.
if (current.Index > maxIndex)
{
break;
}
var minForNode = Math.Max(0, minIndex - current.Index); // this will give the base offset within the node where to start the visitating!
var maxForNode = Math.Min(itemCount - 1, maxIndex - current.Index); //this will five the max offset within this node to visit (protected against overlfow )
if (!processed)
{
var headersNode = current.Node as HeadersFootersGeneratorNode;
if (headersNode != null)
{
var isHeaderFooter = (headersNode.Parent == null);
//If the node is a Headers or Footers node AND the visitorType does not contain HeadersFooters
if ((isHeaderFooter) && ((visitorType & DataGridContextVisitorType.HeadersFooters) == DataGridContextVisitorType.HeadersFooters))
{
GeneratorNodeHelper.ProcessHeadersNodeVisit(headersNode, sourceContext, minForNode, maxForNode, visitor, ref visitWasStopped);
}
else if ((!isHeaderFooter) && ((visitorType & DataGridContextVisitorType.GroupHeadersFooters) == DataGridContextVisitorType.GroupHeadersFooters))
{
GeneratorNodeHelper.ProcessHeadersNodeVisit(headersNode, sourceContext, minForNode, maxForNode, visitor, ref visitWasStopped);
}
processed = true;
}
}
if (!processed)
{
var itemsNode = current.Node as ItemsGeneratorNode;
if (itemsNode != null)
{
if ((visitorType & DataGridContextVisitorType.ItemsBlock) == DataGridContextVisitorType.ItemsBlock)
{
GeneratorNodeHelper.ProcessItemsNodeBlockVisit(
itemsNode, sourceContext,
minForNode, maxForNode,
visitor, visitorType, visitDetails, containsDetails, current.DataIndex,
ref startSourceDataItemIndex, ref endSourceDataItemIndex, ref visitWasStopped);
}
else if (((visitDetails) && (containsDetails)) ||
((visitorType & DataGridContextVisitorType.Items) == DataGridContextVisitorType.Items))
{
GeneratorNodeHelper.ProcessItemsNodeVisit(
itemsNode, sourceContext,
minForNode, maxForNode,
visitor, visitorType, visitDetails, current.DataIndex, ref visitWasStopped);
}
processed = true;
}
}
if (!processed)
{
var groupNode = current.Node as GroupGeneratorNode;
if (groupNode != null)
{
if ((visitorType & DataGridContextVisitorType.Groups) == DataGridContextVisitorType.Groups)
{
visitor.Visit(
sourceContext,
groupNode.CollectionViewGroup,
groupNode.NamesTree,
groupNode.Level,
groupNode.IsExpanded,
groupNode.IsComputedExpanded,
ref visitWasStopped);
}
processed = true;
}
}
if (!processed)
{
throw DataGridException.Create <DataGridInternalException>("Unable to process the visit.", sourceContext.DataGridControl);
}
if (visitWasStopped)
{
break;
}
if (GeneratorNodeHelper.MoveToChild(ref current))
{
continue;
}
if (GeneratorNodeHelper.MoveToFollowing(ref current))
{
continue;
}
break;
}
if ((visitorType & DataGridContextVisitorType.ItemsBlock) == DataGridContextVisitorType.ItemsBlock)
{
if (startSourceDataItemIndex != -1)
{
var stopVisit = false;
visitor.Visit(sourceContext, startSourceDataItemIndex, endSourceDataItemIndex, ref stopVisit);
visitWasStopped = visitWasStopped || stopVisit;
}
}
m_state = current;
this.EnsureState();
}
