GestureRecognizer.IsRecognizerAvailable Property
Important
Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.
Gets a Boolean that indicates whether the gesture recognizer is available on the user's system.
public:
property bool IsRecognizerAvailable { bool get(); };
public bool IsRecognizerAvailable { get; }
member this.IsRecognizerAvailable : bool
Public ReadOnly Property IsRecognizerAvailable As Boolean
true
if the recognition component is available; otherwise, false
.
The following example demonstrates how to determine whether the gesture recognizer is available before calling the Recognize method.
private bool InterpretScratchoutGesture(Stroke stroke)
{
// Attempt to instantiate a recognizer for scratchout gestures.
ApplicationGesture[] gestures = { ApplicationGesture.ScratchOut };
GestureRecognizer recognizer = new GestureRecognizer(gestures);
if (!recognizer.IsRecognizerAvailable)
return false;
// Determine if the stroke was a scratchout gesture.
StrokeCollection gestureStrokes = new StrokeCollection();
gestureStrokes.Add(stroke);
ReadOnlyCollection<GestureRecognitionResult> results = recognizer.Recognize(gestureStrokes);
if (results.Count == 0)
return false;
// Results are returned sorted in order strongest-to-weakest;
// we need only analyze the first (strongest) result.
if (results[0].ApplicationGesture == ApplicationGesture.ScratchOut &&
results[0].RecognitionConfidence == RecognitionConfidence.Strong)
{
// Use the scratchout stroke to perform hit-testing and
// erase existing strokes, as necessary.
return true;
}
else
{
// Not a gesture: display the stroke normally.
return false;
}
}
Private Function InterpretScratchoutGesture(ByVal stroke As Stroke) As Boolean
' Attempt to instantiate a recognizer for scratchout gestures.
Dim gestures() As ApplicationGesture = {ApplicationGesture.ScratchOut}
Dim recognizer As New GestureRecognizer(gestures)
If Not recognizer.IsRecognizerAvailable Then
Return False
End If
' Determine if the stroke was a scratchout gesture.
Dim gestureStrokes As StrokeCollection = New StrokeCollection()
gestureStrokes.Add(stroke)
Dim results As ReadOnlyCollection(Of GestureRecognitionResult)
results = recognizer.Recognize(gestureStrokes)
If results.Count = 0 Then
Return False
End If
' Results are returned sorted in order strongest-to-weakest;
' we need only analyze the first (strongest) result.
If (results(0).ApplicationGesture = ApplicationGesture.ScratchOut) Then
' Use the scratchout stroke to perform hit-testing and
' erase existing strokes, as necessary.
Return True
Else
' Not a gesture: display the stroke normally.
Return False
End If
End Function
Product | Versions |
---|---|
.NET Framework | 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1 |
Windows Desktop | 3.0, 3.1, 5, 6, 7, 8, 9 |
.NET feedback
.NET is an open source project. Select a link to provide feedback: