IContextNode::GetSubNodes method
Gets the direct child nodes of the IContextNode object.
Syntax
HRESULT GetSubNodes(
[out] IContextNodes **ppSubContextNodes
);
Parameters
-
ppSubContextNodes [out]
-
A collection of the IContextNode objects that are direct child nodes of this IContextNode.
Return value
For a description of the return values, see Classes and Interfaces - Ink Analysis.
Remarks
Caution
To avoid a memory leak, call IUnknown::Release on *ppSubContextNodes when you no longer need to use the collection of subnodes.
This returns only the direct child nodes, not all of the descendant nodes.
Examples
This example shows a method, ExploreContextNode, that examines an IContextNode. The method does the following:
- Gets the context node's type.
- Examines specific properties of the node type by calling a helper method, if the context node is an unclassified ink, analysis hint, or custom recognizer node.
- Examines each subnode by calling itself, if the node has subnodes.
- Examines the stroke data for the node by calling a helper method, if the node is an ink leaf node.
HRESULT CMyClass::ExploreContextNode(
IContextNode *pContextNode)
{
// Check for certain types of context nodes.
GUID ContextNodeType;
HRESULT hr = pContextNode->GetType(&ContextNodeType);
if (SUCCEEDED(hr))
{
if (IsEqualGUID(GUID_CNT_UNCLASSIFIEDINK, ContextNodeType))
{
// Call a helper method that explores unclassified ink nodes.
hr = this->ExploreUnclassifiedInkNode(pContextNode);
}
else if (IsEqualGUID(GUID_CNT_ANALYSISHINT, ContextNodeType))
{
// Call a helper method that explores analysis hint nodes.
hr = this->ExploreAnalysisHintNode(pContextNode);
}
else if (IsEqualGUID(GUID_CNT_CUSTOMRECOGNIZER, ContextNodeType))
{
// Call a helper method that explores custom recognizer nodes.
hr = this->ExploreCustomRecognizerNode(pContextNode);
}
if (SUCCEEDED(hr))
{
// Check if this node is a branch or a leaf node.
IContextNodes *pSubNodes = NULL;
hr = pContextNode->GetSubNodes(&pSubNodes);
if (SUCCEEDED(hr))
{
ULONG ulSubNodeCount;
hr = pSubNodes->GetCount(&ulSubNodeCount);
if (SUCCEEDED(hr))
{
if (ulSubNodeCount > 0)
{
// This node has child nodes; explore each child node.
IContextNode *pSubNode = NULL;
for (ULONG index=0; index<ulSubNodeCount; index++)
{
hr = pSubNodes->GetContextNode(index, &pSubNode);
if (SUCCEEDED(hr))
{
// Recursive call to explore the child node of this
// context node.
hr = this->ExploreContextNode(pSubNode);
}
// Release this reference to the child context node.
if (pSubNode != NULL)
{
pSubNode->Release();
pSubNode = NULL;
}
if (FAILED(hr))
{
break;
}
}
}
else
{
// This is a leaf node. Check if it contains stroke data.
ULONG ulStrokeCount;
hr = pContextNode->GetStrokeCount(&ulStrokeCount);
if (SUCCEEDED(hr))
{
if (ulStrokeCount > 0)
{
// This node is an ink leaf node; call helper
// method that explores available stroke data.
hr = this->ExploreNodeStrokeData(pContextNode);
}
}
}
}
}
// Release this reference to the subnodes collection.
if (pSubNodes != NULL)
{
pSubNodes->Release();
pSubNodes = NULL;
}
}
}
return hr;
}
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client |
Windows XP Tablet PC Edition [desktop apps only] |
| Minimum supported server |
None supported |
| Header |
|
| DLL |
|