private DataSourceChangedEventArgs(DataSourceChangeTypeEnum changeType, bool dataWasChanged, string propertyName,
CollectionChangeAction action, object element)
{
ChangeType = changeType;
DataWasUpdated = dataWasChanged;
PropertyName = propertyName;
Action = action;
Element = element;
}
private void OnDataSourceChanged(DataSourceChangeTypeEnum changeType, bool changed)
{
Interlocked.CompareExchange(ref DataSourceChanged, null, null)?.Invoke(this, new DataSourceChangedEventArgs(changeType, changed));
}
public DataSourceChangedEventArgs(DataSourceChangeTypeEnum changeType, bool dataWasChanged)
: this(changeType, dataWasChanged, null, CollectionChangeAction.Refresh, null)
{
}
private bool DataSourceHasChanged_Handler(ObservableSource <T> signalingNode, DataSourceChangeTypeEnum changeType, out PropNode sourcePropNode)
{
sourcePropNode = null;
bool isComplete = false;
BagNode next;
switch (signalingNode.SourceKind)
{
case SourceKindEnum.AbsRoot:
{
System.Diagnostics.Debug.Assert(changeType == DataSourceChangeTypeEnum.ParentHasChanged,
$"Received a DataSourceChanged event from on a node of kind = AbsRoot. " +
$"The DataSourceChangeType should be {nameof(DataSourceChangeTypeEnum.ParentHasChanged)}, but is {changeType}.");
System.Diagnostics.Debug.Assert(ReferenceEquals(signalingNode, _rootListener),
"Received a ParentHasChanged on a node of kind = AbsRoot and the signaling node is not the _rootListener.");
System.Diagnostics.Debug.Assert(_isPathAbsolute,
"Received a ParentHasChanged on a node of kind = AbsRoot, but our 'PathIsAbsolute' property is set to false.");
// We have a new root, start at the beginning.
next = _ourNode.Root;
if (next == null)
{
System.Diagnostics.Debug.WriteLine("OurNode's root is null when processing update to AbsRoot.");
return(isComplete);
}
int nPtr = 0;
isComplete = HandleNodeUpdate(next, _pathElements, _pathListeners, nPtr, out sourcePropNode);
break;
}
case SourceKindEnum.Up:
{
System.Diagnostics.Debug.Assert(changeType == DataSourceChangeTypeEnum.ParentHasChanged, $"DataSourceHasChanged is processing a observable source of kind = {signalingNode.SourceKind}, but the ChangeType does not equal {nameof(DataSourceChangeTypeEnum.ParentHasChanged)}.");
if (GetChangedNode(_ourNode, signalingNode, _isPathAbsolute, _pathElements, out next, out int nPtr))
{
System.Diagnostics.Debug.Assert(nPtr < _pathElements.Length - 1, "GetChangedNode for 'up' PropertyChanged event returned with nPtr beyond next to last node.");
isComplete = HandleNodeUpdate(next, _pathElements, _pathListeners, nPtr, out sourcePropNode);
}
break;
}
case SourceKindEnum.Down:
{
System.Diagnostics.Debug.Assert(changeType == DataSourceChangeTypeEnum.PropertyChanged, $"DataSourceHasChanged is processing a observable source of kind = {signalingNode.SourceKind}, but the ChangeType does not equal {nameof(DataSourceChangeTypeEnum.PropertyChanged)}.");
if (GetChangedNode(_ourNode, signalingNode, _isPathAbsolute, _pathElements, out next, out int nPtr))
{
System.Diagnostics.Debug.Assert(nPtr < _pathElements.Length - 1, "GetChangedNode for 'down' PropertyChanged event returned with nPtr beyond next to last node.");
isComplete = HandleNodeUpdate(next, _pathElements, _pathListeners, nPtr, out sourcePropNode);
}
break;
}
case SourceKindEnum.TerminalNode:
{
System.Diagnostics.Debug.Assert(Complete, "The Complete flag should be set when responding to Terminal node updates.");
System.Diagnostics.Debug.WriteLine("Beginning to proccess property changed event raised from the Terminal node of the source path.");
if (GetChangedNode(_ourNode, signalingNode, _isPathAbsolute, _pathElements, out next, out int nPtr))
{
isComplete = HandleTerminalNodeUpdate(next, _pathElements, nPtr, out sourcePropNode);
}
break;
}
default:
{
throw new InvalidOperationException($"The SourceKind: {signalingNode.SourceKind} is not recognized or is not supported.");
}
}
return(isComplete);
}
