TreeWalker を使用した UI オートメーション要素間の移動
Note
このドキュメントは、System.Windows.Automation 名前空間で定義されているマネージド UI オートメーション クラスを使用する .NET Framework 開発者を対象としています。 UI オートメーションの最新情報については、Windows Automation API の「UI オートメーション」を参照してください。
このトピックには、TreeWalker クラスを使用して、Microsoft UI オートメーション要素間を移動する方法を示すコード例が含まれています。
例 1
次の例では、GetParent を使用して、ルート要素 (デスクトップ) が見つかるまで Microsoft UI オートメーション ツリーをウォークします。 そのすぐ下の要素が、指定された要素の親ウィンドウです。
/// <summary>
/// Retrieves the top-level window that contains the specified UI Automation element.
/// </summary>
/// <param name="element">The contained element.</param>
/// <returns>The containing top-level window element.</returns>
private AutomationElement GetTopLevelWindow(AutomationElement element)
{
TreeWalker walker = TreeWalker.ControlViewWalker;
AutomationElement elementParent;
AutomationElement node = element;
if (node == elementRoot) return node;
do
{
elementParent = walker.GetParent(node);
if (elementParent == AutomationElement.RootElement) break;
node = elementParent;
}
while (true);
return node;
}
''' <summary>
''' Retrieves the top-level window that contains the specified UI Automation element.
''' </summary>
''' <param name="element">The contained element.</param>
''' <returns>The containing top-level window element.</returns>
Private Function GetTopLevelWindow(ByVal element As AutomationElement) As AutomationElement
Dim walker As TreeWalker = TreeWalker.ControlViewWalker
Dim elementParent As AutomationElement
Dim node As AutomationElement = element
If node = elementRoot Then
Return node
End If
Do
elementParent = walker.GetParent(node)
If elementParent = AutomationElement.RootElement Then
Exit Do
End If
node = elementParent
Loop While True
Return node
End Function 'GetTopLevelWindow
End Class
例 2
次の例では、GetFirstChild と GetNextSibling を使用して、コントロール ビュー内にあり、有効になっている Microsoft UI オートメーション要素のサブツリー全体を表示する TreeView を作成します。
/// <summary>
/// Walks the UI Automation tree and adds the control type of each enabled control
/// element it finds to a TreeView.
/// </summary>
/// <param name="rootElement">The root of the search on this iteration.</param>
/// <param name="treeNode">The node in the TreeView for this iteration.</param>
/// <remarks>
/// This is a recursive function that maps out the structure of the subtree beginning at the
/// UI Automation element passed in as rootElement on the first call. This could be, for example,
/// an application window.
/// CAUTION: Do not pass in AutomationElement.RootElement. Attempting to map out the entire subtree of
/// the desktop could take a very long time and even lead to a stack overflow.
/// </remarks>
private void WalkEnabledElements(AutomationElement rootElement, TreeNode treeNode)
{
Condition condition1 = new PropertyCondition(AutomationElement.IsControlElementProperty, true);
Condition condition2 = new PropertyCondition(AutomationElement.IsEnabledProperty, true);
TreeWalker walker = new TreeWalker(new AndCondition(condition1, condition2));
AutomationElement elementNode = walker.GetFirstChild(rootElement);
while (elementNode != null)
{
TreeNode childTreeNode = treeNode.Nodes.Add(elementNode.Current.ControlType.LocalizedControlType);
WalkEnabledElements(elementNode, childTreeNode);
elementNode = walker.GetNextSibling(elementNode);
}
}
''' <summary>
''' Walks the UI Automation tree and adds the control type of each enabled control
''' element it finds to a TreeView.
''' </summary>
''' <param name="rootElement">The root of the search on this iteration.</param>
''' <param name="treeNode">The node in the TreeView for this iteration.</param>
''' <remarks>
''' This is a recursive function that maps out the structure of the subtree beginning at the
''' UI Automation element passed in as rootElement on the first call. This could be, for example,
''' an application window.
''' CAUTION: Do not pass in AutomationElement.RootElement. Attempting to map out the entire subtree of
''' the desktop could take a very long time and even lead to a stack overflow.
''' </remarks>
Private Sub WalkEnabledElements(ByVal rootElement As AutomationElement, ByVal treeNode As TreeNode)
Dim condition1 As New PropertyCondition(AutomationElement.IsControlElementProperty, True)
Dim condition2 As New PropertyCondition(AutomationElement.IsEnabledProperty, True)
Dim walker As New TreeWalker(New AndCondition(condition1, condition2))
Dim elementNode As AutomationElement = walker.GetFirstChild(rootElement)
While (elementNode IsNot Nothing)
Dim childTreeNode As TreeNode = treeNode.Nodes.Add(elementNode.Current.ControlType.LocalizedControlType)
WalkEnabledElements(elementNode, childTreeNode)
elementNode = walker.GetNextSibling(elementNode)
End While
End Sub