/// <summary>
/// Performs actions after a reference's target DOM node has been removed; the
/// default behavior is to remove the node from its parent</summary>
/// <param name="e">Event args describing reference</param>
protected virtual void OnReferentRemoved(ReferenceEventArgs e)
{
// check if node has been removed already; this can happen if it
// has multiple referents that have been removed
DomNode parent = e.Owner.Parent;
if (parent != null)
{
// remove node from parent
e.Owner.RemoveFromParent();
}
}
/// <summary>
/// Performs actions after a reference to an external DOM node is removed</summary>
/// <param name="e">Event args describing reference</param>
protected virtual void OnExternalReferenceRemoved(ReferenceEventArgs e)
{
ExternalReferenceRemoved.Raise(this, e);
}
/// <summary>
/// Performs actions after a reference to an external DOM node is added</summary>
/// <param name="e">Event args describing reference</param>
protected virtual void OnExternalReferenceAdded(ReferenceEventArgs e)
{
}
/// <summary>
/// Performs custom actions on validation Ending events</summary>
/// <param name="sender">Validation context</param>
/// <param name="e">Event args</param>
protected override void OnEnding(object sender, EventArgs e)
{
if (Suspended)
return;
while (m_removed.Count > 0)
{
// get a snapshot of the removed nodes, so we can clear the set, as dangling
// reference handling may result in cascading removals
DomNode[] removedNodes = m_removed.ToArray();
m_removed.Clear();
// update all dangling references to removed node
foreach (DomNode removedNode in removedNodes)
{
List<Pair<DomNode, AttributeInfo>> referenceList;
if (m_nodeReferenceLists.TryGetValue(removedNode, out referenceList))
{
foreach (Pair<DomNode, AttributeInfo> pair in referenceList.ToArray()) // copy, as list may be modified
{
ReferenceEventArgs args = new ReferenceEventArgs(pair.First, pair.Second, removedNode);
ReferentRemoved.Raise(this, args);
OnReferentRemoved(args);
}
// remove the list of references to the removed node
m_nodeReferenceLists.Remove(removedNode);
}
}
}
}
/// <summary>
/// Performs actions after a reference to an external DOM node is removed</summary>
/// <param name="e">Event args describing reference</param>
protected virtual void OnExternalReferenceRemoved(ReferenceEventArgs e)
{
ExternalReferenceRemoved.Raise(this, e);
}
/// <summary>
/// Performs actions after a reference to an external DOM node is added</summary>
/// <param name="e">Event args describing reference</param>
protected virtual void OnExternalReferenceAdded(ReferenceEventArgs e)
{
}
// removes refs from the tracker, and reports removed external refs
private void RemoveReference(DomNode owner, AttributeInfo attributeInfo, DomNode target)
{
List<Pair<DomNode, AttributeInfo>> referenceList;
if (m_nodeReferenceLists.TryGetValue(target, out referenceList))
{
referenceList.Remove(new Pair<DomNode, AttributeInfo>(owner, attributeInfo));
if (referenceList.Count == 0)
{
m_nodeReferenceLists.Remove(target);
}
}
// if target's root isn't the context's root, then it's an external reference
// that is being removed.
DomNode targetRoot = target.GetRoot();
if (DomNode != targetRoot)
{
ReferenceEventArgs e = new ReferenceEventArgs(owner, attributeInfo, target);
OnExternalReferenceRemoved(e);
ExternalReferenceRemoved.Raise(this, e);
}
}
// adds refs to the tracker, and reports added external refs
private void AddReference(DomNode owner, AttributeInfo attributeInfo, DomNode target)
{
List<Pair<DomNode, AttributeInfo>> referenceList;
if (!m_nodeReferenceLists.TryGetValue(target, out referenceList))
{
referenceList = new List<Pair<DomNode, AttributeInfo>>();
m_nodeReferenceLists.Add(target, referenceList);
}
referenceList.Add(new Pair<DomNode, AttributeInfo>(owner, attributeInfo));
// if target's root isn't the context's root, then it's an external reference
// that is being added.
DomNode targetRoot = target.GetRoot();
if (DomNode != targetRoot)
{
ReferenceEventArgs e = new ReferenceEventArgs(owner, attributeInfo, target);
OnExternalReferenceAdded(e);
ExternalReferenceAdded.Raise(this, e);
}
}
