ManipulationStartingEventHandler Délégué

Définition

Espace de noms:

Windows.UI.Xaml.Input

Représente la méthode qui gérera l’événement ManipulationStarting .

public delegate void ManipulationStartingEventHandler(Platform::Object ^ sender, ManipulationStartingRoutedEventArgs ^ e);

/// [Windows.Foundation.Metadata.ContractVersion(Windows.Foundation.UniversalApiContract, 65536)]
/// [Windows.Foundation.Metadata.Guid(282112078, 49124, 17099, 130, 60, 63, 236, 216, 119, 14, 248)]
class ManipulationStartingEventHandler : MulticastDelegate

[Windows.Foundation.Metadata.ContractVersion(typeof(Windows.Foundation.UniversalApiContract), 65536)]
[Windows.Foundation.Metadata.Guid(282112078, 49124, 17099, 130, 60, 63, 236, 216, 119, 14, 248)]
public delegate void ManipulationStartingEventHandler(object sender, ManipulationStartingRoutedEventArgs e);

Public Delegate Sub ManipulationStartingEventHandler(sender As Object, e As ManipulationStartingRoutedEventArgs)

Paramètres

sender

Object

Platform::Object

IInspectable

Objet où le gestionnaire d’événements est attaché.

e

ManipulationStartingRoutedEventArgs

Données d'événement de l'événement.

Attributs

ContractVersionAttribute GuidAttribute

Configuration requise pour Windows

Famille d’appareils	Windows 10 (introduit dans 10.0.10240.0)
API contract	Windows.Foundation.UniversalApiContract (introduit dans v1.0)

Exemples

L’exemple de code suivant illustre le scénario 4 de l’exemple Input. Ce code montre certains modèles d’utilisation pour la manipulation directe à l’aide des événements ManipulationStarting, ManipulationStarted, ManipulationDelta, ManipulationInertiaStarting et ManipulationCompleted .

private TransformGroup _transformGroup;
private MatrixTransform _previousTransform;
private CompositeTransform _compositeTransform;
private bool forceManipulationsToEnd;

public Scenario4()
{
    this.InitializeComponent();
    forceManipulationsToEnd = false;
    ManipulateMe.ManipulationStarting += 
        new ManipulationStartingEventHandler(
            ManipulateMe_ManipulationStarting);
    ManipulateMe.ManipulationStarted += 
        new ManipulationStartedEventHandler(
            ManipulateMe_ManipulationStarted);
    ManipulateMe.ManipulationDelta += 
        new ManipulationDeltaEventHandler(
            ManipulateMe_ManipulationDelta);
    ManipulateMe.ManipulationCompleted += 
        new ManipulationCompletedEventHandler(
            ManipulateMe_ManipulationCompleted);
    ManipulateMe.ManipulationInertiaStarting += 
        new ManipulationInertiaStartingEventHandler(
            ManipulateMe_ManipulationInertiaStarting);
    InitManipulationTransforms();
}

private void InitManipulationTransforms()
{
    _transformGroup = new TransformGroup();
    _compositeTransform = new CompositeTransform();
    _previousTransform = new MatrixTransform() { 
        Matrix = Matrix.Identity };

    _transformGroup.Children.Add(_previousTransform);
    _transformGroup.Children.Add(_compositeTransform);

    ManipulateMe.RenderTransform = _transformGroup;
}

private void ManipulateMe_ManipulationStarting(object sender, 
    ManipulationStartingRoutedEventArgs e)
{
    forceManipulationsToEnd = false;
    e.Handled = true;
}

private void ManipulateMe_ManipulationStarted(
    object sender, ManipulationStartedRoutedEventArgs e)
{
    e.Handled = true;
}

private void ManipulateMe_ManipulationInertiaStarting(
    object sender, ManipulationInertiaStartingRoutedEventArgs e)
{
    e.Handled = true;
}

private void ManipulateMe_ManipulationDelta(
    object sender, ManipulationDeltaRoutedEventArgs e)
{
    if (forceManipulationsToEnd)
    {
        e.Complete();
        return;
    }

    _previousTransform.Matrix = _transformGroup.Value;

    Point center = _previousTransform.TransformPoint(
        new Point(e.Position.X, e.Position.Y));
    _compositeTransform.CenterX = center.X;
    _compositeTransform.CenterY = center.Y;

    _compositeTransform.Rotation = (e.Delta.Rotation * 180) / Math.PI;
    _compositeTransform.ScaleX = 
        _compositeTransform.ScaleY = e.Delta.Scale;
    _compositeTransform.TranslateX = e.Delta.Translation.X;
    _compositeTransform.TranslateY = e.Delta.Translation.Y;

    e.Handled = true;
}

private void ManipulateMe_ManipulationCompleted(object sender, 
    ManipulationCompletedRoutedEventArgs e)
{
    e.Handled = true;
}

private void Scenario4Reset(object sender, RoutedEventArgs e)
{
    Scenario4Reset();
}

void Scenario4Reset()
{
    forceManipulationsToEnd = true;
    ManipulateMe.RenderTransform = null;
    InitManipulationTransforms();
}

Private _transformGroup As TransformGroup
Private _previousTransform As MatrixTransform
Private _compositeTransform As CompositeTransform
Private forceManipulationsToEnd As Boolean

Public Sub New()
    Me.InitializeComponent()
    forceManipulationsToEnd = False
    AddHandler ManipulateMe.ManipulationStarting, AddressOf ManipulateMe_ManipulationStarting
    AddHandler ManipulateMe.ManipulationStarted, AddressOf ManipulateMe_ManipulationStarted
    AddHandler ManipulateMe.ManipulationDelta, AddressOf ManipulateMe_ManipulationDelta
    AddHandler ManipulateMe.ManipulationCompleted, AddressOf ManipulateMe_ManipulationCompleted
    InitManipulationTransforms()
End Sub

''' <summary>
''' Invoked when this page is about to be displayed in a Frame.
''' </summary>
''' <param name="e">Event data that describes how this page was reached.  The Parameter
''' property is typically used to configure the page.</param>
Protected Overrides Sub OnNavigatedTo(e As NavigationEventArgs)
End Sub

Private Sub InitManipulationTransforms()
    _transformGroup = New TransformGroup()
    _compositeTransform = New CompositeTransform()
    _previousTransform = New MatrixTransform() With { _
        .Matrix = Matrix.Identity _
    }

    _transformGroup.Children.Add(_previousTransform)
    _transformGroup.Children.Add(_compositeTransform)

    ManipulateMe.RenderTransform = _transformGroup
End Sub

Private Sub ManipulateMe_ManipulationStarting(sender As Object, e As ManipulationStartingRoutedEventArgs)
    forceManipulationsToEnd = False
    e.Handled = True
End Sub

Private Sub ManipulateMe_ManipulationStarted(sender As Object, e As ManipulationStartedRoutedEventArgs)
    e.Handled = True
End Sub

Private Sub ManipulateMe_ManipulationDelta(sender As Object, e As ManipulationDeltaRoutedEventArgs)
    If forceManipulationsToEnd Then
        e.Complete()
        Exit Sub
    End If

    _previousTransform.Matrix = _transformGroup.Value

    Dim center As Point = _previousTransform.TransformPoint(New Point(e.Position.X, e.Position.Y))
    _compositeTransform.CenterX = center.X
    _compositeTransform.CenterY = center.Y

    _compositeTransform.Rotation = (e.Delta.Rotation * 180) / Math.PI
    _compositeTransform.ScaleX = InlineAssignHelper(_compositeTransform.ScaleY, e.Delta.Scale)
    _compositeTransform.TranslateX = e.Delta.Translation.X
    _compositeTransform.TranslateY = e.Delta.Translation.Y

    e.Handled = True
End Sub

Private Sub ManipulateMe_ManipulationCompleted(sender As Object, e As ManipulationCompletedRoutedEventArgs)
    e.Handled = True
End Sub

Private Sub Scenario4ResetMethod(sender As Object, e As RoutedEventArgs)
    Reset()
End Sub

Private Sub Reset()
    forceManipulationsToEnd = True
    ManipulateMe.RenderTransform = Nothing
    InitManipulationTransforms()
End Sub
Private Shared Function InlineAssignHelper(Of T)(ByRef target As T, value As T) As T
    target = value
    Return value
End Function