利用 UI 自動化公開資料表的內容
.gif "注意事項") 注意事項 |
|---|
這份文件適用於想要使用 System.Windows.Automation 命名空間中定義之 Managed UI Automation 類別的 .NET Framework 開發人員。如需 UI Automation 的最新資訊，請參閱 Windows Automation API：使用者介面自動化 (英文)。 |
本主題說明如何使用 Microsoft UI Automation，以公開表格式控制項內每一個儲存格的內容及內建屬性。
範例
下列程式碼範例說明如何取得代表表格儲存格內容的 AutomationElement，同時也會取得儲存格屬性，如資料列與資料行索引、資料列與資料行跨距，以及資料列與資料行行首資訊。 本範例使用焦點變更事件處理常式，以模擬實作 UI Automation的表格式控制項之鍵盤來回移動。 每一個表格項目的資訊都會公開在焦點變更事件上。
| 注意事項 |
|---|
由於焦點變更是全域桌面事件，所以必須篩選表格以外的焦點變更事件。如需相關的實作，請參閱 TrackFocus Sample。 |
''' -------------------------------------------------------------------
''' <summary>
''' Starts the target application and returns the AutomationElement
''' obtained from the targets window handle.
''' </summary>
''' <param name="exe">
''' The target application.
''' </param>
''' <param name="filename">
''' The text file to be opened in the target application
''' </param>
''' <returns>
''' An AutomationElement representing the target application.
''' </returns>
''' -------------------------------------------------------------------
Private Function StartTarget(ByVal exe As String, ByVal filename As String) As AutomationElement
' Start text editor and load with a text file.
Dim p As Process = Process.Start(exe, filename)
' targetApp --> the root AutomationElement
Dim targetApp As AutomationElement = _
AutomationElement.FromHandle(p.MainWindowHandle)
Return targetApp
End Function
...
''' -------------------------------------------------------------------
''' <summary>
''' Obtain the table control of interest from the target application.
''' </summary>
''' <param name="targetApp">
''' The target application.
''' </param>
''' <returns>
''' An AutomationElement representing a table control.
''' </returns>
''' -------------------------------------------------------------------
Private Function GetTableElement(ByVal targetApp As AutomationElement) As AutomationElement
' The control type we're looking for; in this case 'Document'
Dim cond1 As PropertyCondition = _
New PropertyCondition( _
AutomationElement.ControlTypeProperty, _
ControlType.Table)
' The control pattern of interest; in this case 'TextPattern'.
Dim cond2 As PropertyCondition = _
New PropertyCondition( _
AutomationElement.IsTablePatternAvailableProperty, _
True)
Dim tableCondition As AndCondition = New AndCondition(cond1, cond2)
Dim targetTableElement As AutomationElement = _
targetApp.FindFirst(TreeScope.Descendants, tableCondition)
' If targetTableElement is null then a suitable table control
' was not found.
Return targetTableElement
End Function
...
'''--------------------------------------------------------------------
''' <summary>
''' Obtains a TableItemPattern control pattern from an
''' AutomationElement.
''' </summary>
''' <param name="targetControl">
''' The AutomationElement of interest.
''' </param>
''' <returns>
''' A TableItemPattern object.
''' </returns>
'''--------------------------------------------------------------------
Private Function GetTableItemPattern( _
ByVal targetControl As AutomationElement) As TableItemPattern
Dim tableItemPattern As TableItemPattern = Nothing
Try
tableItemPattern = DirectCast( _
targetControl.GetCurrentPattern(tableItemPattern.Pattern), TableItemPattern)
Catch exc As InvalidOperationException
' Object doesn't support the
' GridPattern control pattern
Return Nothing
End Try
Return tableItemPattern
End Function 'GetTableItemPattern
...
'''--------------------------------------------------------------------
''' <summary>
''' Obtains a TablePattern control pattern from an
''' AutomationElement.
''' </summary>
''' <param name="targetControl">
''' The AutomationElement of interest.
''' </param>
''' <returns>
''' A TablePattern object.
''' </returns>
'''--------------------------------------------------------------------
Private Function GetTablePattern( _
ByVal targetControl As AutomationElement) As TablePattern
Dim tablePattern As TablePattern = Nothing
Try
tablePattern = DirectCast( _
targetControl.GetCurrentPattern(tablePattern.Pattern), _
TablePattern)
Catch exc As InvalidOperationException
' Object doesn't support the
' TablePattern control pattern
Return Nothing
End Try
Return tablePattern
End Function 'GetTablePattern
...
'''--------------------------------------------------------------------
''' <summary>
''' Set up table item event listeners.
''' </summary>
''' <remarks>
''' The event listener is essentially a focus change listener.
''' Since this is a global desktop listener, a filter would be required
''' to ignore focus change events outside the table.
''' </remarks>
'''--------------------------------------------------------------------
Private Sub SetTableItemEventListeners( _
ByVal targetControl As AutomationElement)
Dim tableItemFocusChangedListener As AutomationFocusChangedEventHandler = _
AddressOf OnTableItemFocusChange
Automation.AddAutomationFocusChangedEventHandler( _
tableItemFocusChangedListener)
End Sub 'SetTableItemEventListeners
...
'''--------------------------------------------------------------------
''' <summary>
''' Event handler for table item focus change.
''' Can be used to track traversal of individual table items
''' within a table.
''' </summary>
''' <param name="src">Object that raised the event.</param>
''' <param name="e">Event arguments.</param>
'''--------------------------------------------------------------------
Private Sub OnTableItemFocusChange( _
ByVal src As Object, ByVal e As AutomationFocusChangedEventArgs)
' Make sure the element still exists. Elements such as tooltips
' can disappear before the event is processed.
Dim sourceElement As AutomationElement
Try
sourceElement = DirectCast(src, AutomationElement)
Catch exc As ElementNotAvailableException
Return
End Try
' Get a TableItemPattern from the source of the event.
Dim tableItemPattern As TableItemPattern = _
GetTableItemPattern(sourceElement)
If tableItemPattern Is Nothing Then
Return
End If
' Get a TablePattern from the container of the current element.
Dim tablePattern As TablePattern = _
GetTablePattern(tableItemPattern.Current.ContainingGrid)
If tablePattern Is Nothing Then
Return
End If
Dim tableItem As AutomationElement = Nothing
Try
tableItem = tablePattern.GetItem( _
tableItemPattern.Current.Row, tableItemPattern.Current.Column)
Catch exc As ArgumentOutOfRangeException
' If the requested row coordinate is larger than the RowCount
' or the column coordinate is larger than the ColumnCount.
' -- OR --
' If either of the requested row or column coordinates
' is less than zero.
' TO DO: error handling.
End Try
' Further event processing can be done at this point.
' For the purposes of this sample we can just record item properties.
Dim controlType As String = _
tableItem.Current.ControlType.LocalizedControlType
Dim columnHeaders As AutomationElement() = _
tableItemPattern.Current.GetColumnHeaderItems()
Dim rowHeaders As AutomationElement() = _
tableItemPattern.Current.GetRowHeaderItems()
Dim itemRow As Integer = tableItemPattern.Current.Row
Dim itemColumn As Integer = tableItemPattern.Current.Column
Dim itemRowSpan As Integer = tableItemPattern.Current.RowSpan
Dim itemColumnSpan As Integer = tableItemPattern.Current.ColumnSpan
End Sub 'OnTableItemFocusChange
'''--------------------------------------------------------------------
''' <summary>
''' Handles the application shutdown.
''' </summary>
''' <param name="args">Event arguments.</param>
'''--------------------------------------------------------------------
Protected Overrides Sub OnExit(ByVal args As System.Windows.ExitEventArgs)
Automation.RemoveAllEventHandlers()
MyBase.OnExit(args)
End Sub 'OnExit
/// -------------------------------------------------------------------
/// <summary>
/// Starts the target application and returns the AutomationElement
/// obtained from the targets window handle.
/// </summary>
/// <param name="exe">
/// The target application.
/// </param>
/// <param name="filename">
/// The text file to be opened in the target application
/// </param>
/// <returns>
/// An AutomationElement representing the target application.
/// </returns>
/// -------------------------------------------------------------------
private AutomationElement StartTarget(string exe, string filename)
{
// Start text editor and load with a text file.
Process p = Process.Start(exe, filename);
// targetApp --> the root AutomationElement
AutomationElement targetApp =
AutomationElement.FromHandle(p.MainWindowHandle);
return targetApp;
}
...
/// -------------------------------------------------------------------
/// <summary>
/// Obtain the table control of interest from the target application.
/// </summary>
/// <param name="targetApp">
/// The target application.
/// </param>
/// <returns>
/// An AutomationElement representing a table control.
/// </returns>
/// -------------------------------------------------------------------
private AutomationElement GetTableElement(AutomationElement targetApp)
{
// The control type we're looking for; in this case 'Document'
PropertyCondition cond1 =
new PropertyCondition(
AutomationElement.ControlTypeProperty,
ControlType.Table);
// The control pattern of interest; in this case 'TextPattern'.
PropertyCondition cond2 =
new PropertyCondition(
AutomationElement.IsTablePatternAvailableProperty,
true);
AndCondition tableCondition = new AndCondition(cond1, cond2);
AutomationElement targetTableElement =
targetApp.FindFirst(TreeScope.Descendants, tableCondition);
// If targetTableElement is null then a suitable table control
// was not found.
return targetTableElement;
}
...
///--------------------------------------------------------------------
/// <summary>
/// Obtains a TableItemPattern control pattern from an
/// AutomationElement.
/// </summary>
/// <param name="targetControl">
/// The AutomationElement of interest.
/// </param>
/// <returns>
/// A TableItemPattern object.
/// </returns>
///--------------------------------------------------------------------
private TableItemPattern GetTableItemPattern(
AutomationElement targetControl)
{
TableItemPattern tableItemPattern = null;
try
{
tableItemPattern =
targetControl.GetCurrentPattern(
TableItemPattern.Pattern)
as TableItemPattern;
}
// Object doesn't support the
// TableItemPattern control pattern
catch (InvalidOperationException)
{
return null;
}
return tableItemPattern;
}
...
///--------------------------------------------------------------------
/// <summary>
/// Obtains a TablePattern control pattern from an
/// AutomationElement.
/// </summary>
/// <param name="targetControl">
/// The AutomationElement of interest.
/// </param>
/// <returns>
/// A TablePattern object.
/// </returns>
///--------------------------------------------------------------------
private TablePattern GetTablePattern(
AutomationElement targetControl)
{
TablePattern tablePattern = null;
try
{
tablePattern =
targetControl.GetCurrentPattern(
TablePattern.Pattern)
as TablePattern;
}
// Object doesn't support the
// TablePattern control pattern
catch (InvalidOperationException)
{
return null;
}
return tablePattern;
}
...
///--------------------------------------------------------------------
/// <summary>
/// Set up table item event listeners.
/// </summary>
/// <remarks>
/// The event listener is essentially a focus change listener.
/// Since this is a global desktop listener, a filter would be required
/// to ignore focus change events outside the table.
/// </remarks>
///--------------------------------------------------------------------
private void SetTableItemEventListeners()
{
AutomationFocusChangedEventHandler tableItemFocusChangedListener =
new AutomationFocusChangedEventHandler(OnTableItemFocusChange);
Automation.AddAutomationFocusChangedEventHandler(
tableItemFocusChangedListener);
}
...
///--------------------------------------------------------------------
/// <summary>
/// Event handler for table item focus change.
/// Can be used to track traversal of individual table items
/// within a table.
/// </summary>
/// <param name="src">Object that raised the event.</param>
/// <param name="e">Event arguments.</param>
///--------------------------------------------------------------------
private void OnTableItemFocusChange(
object src, AutomationFocusChangedEventArgs e)
{
// Make sure the element still exists. Elements such as tooltips
// can disappear before the event is processed.
AutomationElement sourceElement;
try
{
sourceElement = src as AutomationElement;
}
catch (ElementNotAvailableException)
{
return;
}
// Get a TableItemPattern from the source of the event.
TableItemPattern tableItemPattern =
GetTableItemPattern(sourceElement);
if (tableItemPattern == null)
{
return;
}
// Get a TablePattern from the container of the current element.
TablePattern tablePattern =
GetTablePattern(tableItemPattern.Current.ContainingGrid);
if (tablePattern == null)
{
return;
}
AutomationElement tableItem = null;
try
{
tableItem = tablePattern.GetItem(
tableItemPattern.Current.Row,
tableItemPattern.Current.Column);
}
catch (ArgumentOutOfRangeException)
{
// If the requested row coordinate is larger than the RowCount
// or the column coordinate is larger than the ColumnCount.
// -- OR --
// If either of the requested row or column coordinates
// is less than zero.
// TO DO: error handling.
}
// Further event processing can be done at this point.
// For the purposes of this sample we can just record item properties.
string controlType =
tableItem.Current.ControlType.LocalizedControlType;
AutomationElement[] columnHeaders =
tableItemPattern.Current.GetColumnHeaderItems();
AutomationElement[] rowHeaders =
tableItemPattern.Current.GetRowHeaderItems();
int itemRow = tableItemPattern.Current.Row;
int itemColumn = tableItemPattern.Current.Column;
int itemRowSpan = tableItemPattern.Current.RowSpan;
int itemColumnSpan = tableItemPattern.Current.ColumnSpan;
}
///--------------------------------------------------------------------
/// <summary>
/// Handles the application shutdown.
/// </summary>
/// <param name="args">Event arguments.</param>
///--------------------------------------------------------------------
protected override void OnExit(System.Windows.ExitEventArgs args)
{
Automation.RemoveAllEventHandlers();
base.OnExit(args);
}