InkCanvas.HitTestSelection(Point) Metodo

Definizione

Spazio dei nomi:

System.Windows.Controls

Assembly:

PresentationFramework.dll

Restituisce un valore che indica quale parte dello strumento decorativo visuale di selezione interseca o circonda il punto specificato.

public:
 System::Windows::Controls::InkCanvasSelectionHitResult HitTestSelection(System::Windows::Point point);

public System.Windows.Controls.InkCanvasSelectionHitResult HitTestSelection (System.Windows.Point point);

member this.HitTestSelection : System.Windows.Point -> System.Windows.Controls.InkCanvasSelectionHitResult

Public Function HitTestSelection (point As Point) As InkCanvasSelectionHitResult

Parametri

point

Point

Il punto da sottoporre a hit testing.

Restituisce

InkCanvasSelectionHitResult

Un valore che indica quale parte dello strumento decorativo visuale di selezione interseca o circonda il punto specificato.

Esempio

Nell'esempio seguente viene illustrato come usare HitTestSelection per determinare se creare un DataObject oggetto per avviare il trascinamento della selezione. Per implementare il trascinamento della selezione tra due InkCanvas oggetti, vedere Procedura: Trascinare e rilasciare input penna.

void InkCanvas_PreviewMouseDown(object sender, MouseEventArgs e)
{
    InkCanvas ic = (InkCanvas)sender;
    
    Point pt = e.GetPosition(ic);

    // If the user is moving selected strokes, prepare the strokes to be
    // moved to another InkCanvas.
    if (ic.HitTestSelection(pt) == 
        InkCanvasSelectionHitResult.Selection)
    {
        StrokeCollection selectedStrokes = ic.GetSelectedStrokes();
        StrokeCollection strokesToMove = selectedStrokes.Clone();
    
        // Remove the offset of the selected strokes so they
        // are positioned when the strokes are dropped.
        Rect inkBounds = strokesToMove.GetBounds();
        TranslateStrokes(strokesToMove, -inkBounds.X, -inkBounds.Y);
        
        // Perform drag and drop.
        MemoryStream ms = new MemoryStream();
        strokesToMove.Save(ms);
        DataObject dataObject = new DataObject(
            StrokeCollection.InkSerializedFormat, ms);
        
        DragDropEffects effects = 
            DragDrop.DoDragDrop(ic, dataObject, 
                                DragDropEffects.Move);

        if ((effects & DragDropEffects.Move) == 
             DragDropEffects.Move)
        {
            // Remove the selected strokes 
            // from the current InkCanvas.
            ic.Strokes.Remove(selectedStrokes);
        }
    }
}

Private Sub InkCanvas_PreviewMouseDown(ByVal sender As Object, _
                               ByVal e As MouseButtonEventArgs)

    Dim ic As InkCanvas = CType(sender, InkCanvas)

    Dim pt As Point = e.GetPosition(ic)

    ' If the user is moving selected strokes, prepare the strokes to be
    ' moved to another InkCanvas.
    If ic.HitTestSelection(pt) = InkCanvasSelectionHitResult.Selection Then

        Dim selectedStrokes As StrokeCollection = _
                               ic.GetSelectedStrokes()

        Dim strokesToMove As StrokeCollection = _
                             selectedStrokes.Clone()

        ' Remove the offset of the selected strokes so they
        ' are positioned when the strokes are dropped.
        Dim inkBounds As Rect = strokesToMove.GetBounds()
        TranslateStrokes(strokesToMove, -inkBounds.X, -inkBounds.Y)

        ' Perform drag and drop.
        Dim ms As New MemoryStream()
        strokesToMove.Save(ms)

        Dim dataObject As New DataObject _
            (StrokeCollection.InkSerializedFormat, ms)

        Dim effects As DragDropEffects = _
            DragDrop.DoDragDrop(ic, dataObject, DragDropEffects.Move)

        If (effects And DragDropEffects.Move) = DragDropEffects.Move Then

            ' Remove the selected strokes from the current InkCanvas.
            ic.Strokes.Remove(selectedStrokes)
        End If
    End If

End Sub

Commenti

Utilizzare il HitTestSelection metodo per determinare se il punto si trova all'interno dei limiti di una selezione del tratto o su uno degli otto handle. Ciò è utile quando si eseguono operazioni di trascinamento della selezione.