GetTextRangeFromStrokes Method
GetTextRangeFromStrokes Method |
Returns the smallest range of recognized text for which the recognizer can return an alternate that contains a known InkStrokes collection.
Declaration
[C++]
HRESULT GetTextRangeFromStrokes (
[in] IInkStrokes* strokes,
[in,out] long* selectionStart,
[in,out] long* selectionLength
);
[Microsoft® Visual Basic® 6.0]
Public Sub GetTextRangeFromStrokes( _
strokes As InkStrokes, _
selectionStart As Long, _
selectionLength As Long _
)
Parameters
strokes
[in] The collection of strokes for which to find the containing alternate.
selectionStart
[in, out] The start position of the range of recognized text within the alternate object on which this method was called that matches the smallest alternate that contains the passed-in strokes.
selectionLength
[in, out] The length of the text within the range of recognized text of the smallest alternate that contains the passed-in strokes.
Remarks
Use this method to retrieve the text that corresponds to a specified range of strokes. For example, consider a collection of strokes, "how are you", that was drawn using nine strokes (one for each letter and three for each word). If a collection that consists of the sixth and seventh strokes is passed in, corresponding to characters "e" and "y", the text range returned matches the alternate containing "are you" and the selection start and length matches this substring.
Example
[Visual Basic 6.0]
This Visual Basic 6.0 example demonstrates calling the GetTextRangeFromStrokes method on the TopAlternate property of an IInkRecognitionResult object, theRecognitionResult, passing in an InkStrokes collection from within the strokes that make up the recognition result in theStrokes. This example starts with a standard .exe application, adds a reference to the Microsoft Tablet PC Type Library, and has a text box Text1 and a check box HitTestMode added to the form. Ink is collected and recognized with the top alternate placed in the text box. When the hit test mode check box is checked, a mouse click calls HitTestCircle to find the containing collection of strokes with GetStrokesFromTextRange and colors it red, and finds the matching text range with GetTextRangeFromStrokes and selects it in the text box.
Option Explicit
Dim WithEvents theInkCollector As InkCollector
Dim WithEvents theRecognizerContext As InkRecognizerContext
Dim theRecognitionResult As IInkRecognitionResult
Dim hasRecoResult As Boolean
Dim theStrokes As InkStrokes
Private Sub HitTestMode_Click()
theInkCollector.Enabled = Not theInkCollector.Enabled
End Sub
Private Sub Form_Load()
ScaleMode = vbPixels
'Initialize the InkCollector
Set theInkCollector = New InkCollector
theInkCollector.hWnd = Me.hWnd
theInkCollector.Enabled = True
'Create new RecognizerContext
Dim theRecognizers As New InkRecognizers
Dim theRecognizer As IInkRecognizer
Set theRecognizer = theRecognizers.GetDefaultRecognizer
Set theRecognizerContext = theRecognizer.CreateRecognizerContext
'Initialize the recognizer's strokes
'and assign them to the RecognizerContext
Set theStrokes = theInkCollector.Ink.Strokes
Set theRecognizerContext.Strokes = theStrokes
'Clear the hit test check box
HitTestMode.Value = 0
hasRecoResult = False
End Sub
Private Sub Form_MouseDown( _
Button As Integer, Shift As Integer, X As Single, Y As Single)
Dim inkX As Long
Dim inkY As Long
Dim hitStrokes As InkStrokes
Dim AltStrokes As InkStrokes
' Convert the mouse down to ink space coordinates
If hasRecoResult And HitTestMode.Value = 1 Then
inkX = CLng(X)
inkY = CLng(Y)
theInkCollector.Renderer.PixelToInkSpace Form1.hDC, inkX, inkY
'Get the stroke set hit by the mouse (within a radius
'of 200 HIMETRIC) and color it red.
Set hitStrokes = theInkCollector.Ink.HitTestCircle(inkX, inkY, 200)
If hitStrokes.Count > 0 Then
Set AltStrokes = _
theRecognitionResult.TopAlternate.GetStrokesFromStrokeRanges(hitStrokes)
Dim theStroke As IInkStrokeDisp
For Each theStroke In theInkCollector.Ink.Strokes
theStroke.DrawingAttributes.Color = RGB(0, 0, 0)
Next
For Each theStroke In AltStrokes
theStroke.DrawingAttributes.Color = RGB(255, 0, 0)
Next
Dim SelStart As Long
Dim SelLength As Long
theRecognitionResult.TopAlternate.GetTextRangeFromStrokes _
hitStrokes, SelStart, SelLength
Text1.SelStart = SelStart
Text1.SelLength = SelLength
Text1.SetFocus
Form1.Refresh
End If
End If
End Sub
Private Sub theRecognizerContext_RecognitionWithAlternates( _
ByVal RecognitionResult As IInkRecognitionResult, _
ByVal CustomData As Variant, _
ByVal RecognitionStatus As MSINKAUTLib.InkRecognitionStatus)
Set theRecognitionResult = RecognitionResult
'Update the text box with the top result
Text1.Text = theRecognitionResult.TopString
hasRecoResult = True
End Sub
Private Sub theInkCollector_Stroke( _
ByVal Cursor As MSINKAUTLib.IInkCursor, _
ByVal Stroke As MSINKAUTLib.IInkStrokeDisp, _
Cancel As Boolean)
'When a new stroke is collected, add it to
'the RecognizerContext's strokes collection
theStrokes.Add Stroke
'Tell the RecognizerContext to recognize
theRecognizerContext.BackgroundRecognizeWithAlternates
End Sub