internal void OnNodeInvalidated(TreeGridNodeReference invalidatedNodeRef)
{
bool updateNeeded = false;
if (invalidatedNodeRef.Equals(this.currentNode))
{
SetCurrentNode(null);
updateNeeded = true;
}
if (this.selectedNodeReferences.ContainsKey(invalidatedNodeRef))
{
RemoveNodeFromSelection(invalidatedNodeRef);
updateNeeded = true;
}
if (!updateNeeded)
{
updateNeeded = this.visibleRows.Any(r => r.NodeReference.Equals(invalidatedNodeRef));
}
if (updateNeeded)
{
InvalidateRowLayout(false);
}
}
TreeGridRow GetRowForNode(TreeGridNodeReference nodeRef)
{
TreeGridRow row;
if (this.rowCache.TryGetValue(nodeRef, out row))
{
// Found in the cache. That means the row is already in the canvas, and already has
// the correct data. It may need its IsCurrent/IsSelected flags set, but other than
// that we just need to position it vertically.
Debug.Assert(row.NodeReference.Equals(nodeRef));
row.IsCurrent = (nodeRef.Equals(this.currentNode));
row.IsSelected = this.selectedNodeReferences.ContainsKey(nodeRef);
row.UpdateExpansionState();
MoveRowToTopOfUsedList(row);
if (this.fullRowLayoutRequired)
{
row.Width = double.NaN;
row.Measure(infiniteSize);
CollectDesiredColumnWidths(row);
}
else
{
row.Width = this.headerRow.DesiredSize.Width;
}
}
else if ((this.rowCache.Count >= ((this.canvas.ActualHeight / this.headerRow.ActualHeight) * CachedPageCount)) &&
(this.tailOfRowCache != null) && (this.tailOfRowCache.lastLayoutPassUsed != this.rowLayoutPass))
{
// Not in the cache with that row data, but the cache is full and thus has rows available for recycling. Use the oldest one.
// it will be in the cache, but keyed under a different node. We need to remove it using that key (row.NodeReference)
// and then update the row and add it to the cache with the new node reference key.
row = this.tailOfRowCache;
this.rowCache.Remove(row.NodeReference);
row.UpdateRowData(nodeRef, nodeRef.Equals(this.currentNode), this.selectedNodeReferences.ContainsKey(nodeRef));
if (this.fullRowLayoutRequired)
{
row.Width = double.NaN;
row.Measure(infiniteSize);
CollectDesiredColumnWidths(row);
}
else
{
row.Width = this.headerRow.DesiredSize.Width;
row.Measure(infiniteSize);
}
this.rowCache.Add(row.NodeReference, row);
MoveRowToTopOfUsedList(row);
}
else
{
// Not in the cache, and we haven't created a full cache of rows yet. Create a new one now.
row = new TreeGridRow(this, false);
this.canvas.Children.Add(row);
row.UpdateRowData(nodeRef, nodeRef.Equals(this.currentNode), this.selectedNodeReferences.ContainsKey(nodeRef));
if (this.fullRowLayoutRequired)
{
row.Width = double.NaN;
row.UpdateLayout();
CollectDesiredColumnWidths(row);
}
else
{
row.Width = this.headerRow.DesiredSize.Width;
row.UpdateLayout();
}
// NOTE: Very important that we use the row's NodeReference value as the key here, because we need to make sure the
// lifetime of the key outlives the lifetime of the row. (If we used nodeRef, for example, it gets mutated as we
// progress through the paint, and then gets disposed at the end.)
this.rowCache.Add(row.NodeReference, row);
AddRowToUsedList(row);
}
return row;
}