| private OnDeleted ( DelayedEvents delayedEvents ) : void | ||
| delayedEvents | DelayedEvents | |
| return | void | |
public void RemoveText(int offset, int length, DelayedEvents delayedEvents)
{
//Log("RemoveText(" + offset + ", " + length + ")");
if (length == 0 || root == null || offset >= root.totalLength)
{
return;
}
TextAnchorNode node = FindNode(ref offset);
while (node != null && offset + length > node.length)
{
TextAnchor anchor = (TextAnchor)node.Target;
if (anchor != null && anchor.SurviveDeletion)
{
// shorten node
length -= node.length - offset;
node.length = offset;
offset = 0;
UpdateAugmentedData(node);
node = node.Successor;
}
else
{
// delete node
TextAnchorNode s = node.Successor;
length -= node.length;
RemoveNode(node);
// we already deleted the node, don't delete it twice
nodesToDelete.Remove(node);
if (anchor != null)
{
anchor.OnDeleted(delayedEvents);
}
node = s;
}
}
if (node != null)
{
node.length -= length;
UpdateAugmentedData(node);
}
DeleteMarkedNodes();
}
public void HandleTextChange(OffsetChangeMapEntry entry, DelayedEvents delayedEvents)
{
//Log("HandleTextChange(" + entry + ")");
if (entry.RemovalLength == 0)
{
// This is a pure insertion.
// Unlike a replace with removal, a pure insertion can result in nodes at the same location
// to split depending on their MovementType.
// Thus, we handle this case on a separate code path
// (the code below looks like it does something similar, but it can only split
// the set of deletion survivors, not all nodes at an offset)
InsertText(entry.Offset, entry.InsertionLength, entry.DefaultAnchorMovementIsBeforeInsertion);
return;
}
// When handling a replacing text change, we need to:
// - find all anchors in the deleted segment and delete them / move them to the appropriate
// surviving side.
// - adjust the segment size between the left and right side
int offset = entry.Offset;
int remainingRemovalLength = entry.RemovalLength;
// if the text change is happening after the last anchor, we don't have to do anything
if (root == null || offset >= root.totalLength)
{
return;
}
TextAnchorNode node = FindNode(ref offset);
TextAnchorNode firstDeletionSurvivor = null;
// go forward through the tree and delete all nodes in the removal segment
while (node != null && offset + remainingRemovalLength > node.length)
{
TextAnchor anchor = (TextAnchor)node.Target;
if (anchor != null && (anchor.SurviveDeletion || entry.RemovalNeverCausesAnchorDeletion))
{
if (firstDeletionSurvivor == null)
{
firstDeletionSurvivor = node;
}
// This node should be deleted, but it wants to survive.
// We'll just remove the deleted length segment, so the node will be positioned
// in front of the removed segment.
remainingRemovalLength -= node.length - offset;
node.length = offset;
offset = 0;
UpdateAugmentedData(node);
node = node.Successor;
}
else
{
// delete node
TextAnchorNode s = node.Successor;
remainingRemovalLength -= node.length;
RemoveNode(node);
// we already deleted the node, don't delete it twice
nodesToDelete.Remove(node);
if (anchor != null)
{
anchor.OnDeleted(delayedEvents);
}
node = s;
}
}
// 'node' now is the first anchor after the deleted segment.
// If there are no anchors after the deleted segment, 'node' is null.
// firstDeletionSurvivor was set to the first node surviving deletion.
// Because all non-surviving nodes up to 'node' were deleted, the node range
// [firstDeletionSurvivor, node) now refers to the set of all deletion survivors.
// do the remaining job of the removal
if (node != null)
{
node.length -= remainingRemovalLength;
Debug.Assert(node.length >= 0);
}
if (entry.InsertionLength > 0)
{
// we are performing a replacement
if (firstDeletionSurvivor != null)
{
// We got deletion survivors which need to be split into BeforeInsertion
// and AfterInsertion groups.
// Take care that we don't regroup everything at offset, but only the deletion
// survivors - from firstDeletionSurvivor (inclusive) to node (exclusive).
// This ensures that nodes immediately before or after the replaced segment
// stay where they are (independent from their MovementType)
PerformInsertText(firstDeletionSurvivor, node, entry.InsertionLength, entry.DefaultAnchorMovementIsBeforeInsertion);
}
else if (node != null)
{
// No deletion survivors:
// just perform the insertion
node.length += entry.InsertionLength;
}
}
if (node != null)
{
UpdateAugmentedData(node);
}
DeleteMarkedNodes();
}
