diff options
Diffstat (limited to 'Xamarin.Forms.Platform.WP8/VisualElementTracker.cs')
| -rw-r--r-- | Xamarin.Forms.Platform.WP8/VisualElementTracker.cs | 370 |
1 files changed, 370 insertions, 0 deletions
diff --git a/Xamarin.Forms.Platform.WP8/VisualElementTracker.cs b/Xamarin.Forms.Platform.WP8/VisualElementTracker.cs new file mode 100644 index 00000000..8211ec63 --- /dev/null +++ b/Xamarin.Forms.Platform.WP8/VisualElementTracker.cs @@ -0,0 +1,370 @@ +using System; +using System.Collections; +using System.Collections.Generic; +using System.ComponentModel; +using System.Linq; +using System.Windows; +using System.Windows.Input; +using System.Windows.Media; + +namespace Xamarin.Forms.Platform.WinPhone +{ + public abstract class VisualElementTracker : IDisposable + { + public abstract FrameworkElement Child { get; set; } + + public abstract void Dispose(); + + public event EventHandler Updated; + + protected void OnUpdated() + { + if (Updated != null) + Updated(this, EventArgs.Empty); + } + } + + public class VisualElementTracker<TModel, TElement> : VisualElementTracker where TModel : VisualElement where TElement : FrameworkElement + { + FrameworkElement _child; + bool _disposed; + TElement _element; + + bool _invalidateArrangeNeeded; + bool _isPanning; + bool _isPinching; + + TModel _model; + bool _touchFrameReportedEventSet; + int _touchPoints = 1; + + public override FrameworkElement Child + { + get { return _child; } + set + { + if (_child == value) + return; + _child = value; + UpdateNativeControl(); + } + } + + public TElement Element + { + get { return _element; } + set + { + if (_element == value) + return; + + if (_element != null) + { + _element.Tap -= ElementOnTap; + _element.DoubleTap -= ElementOnDoubleTap; + _element.ManipulationDelta -= OnManipulationDelta; + _element.ManipulationCompleted -= OnManipulationCompleted; + } + + _element = value; + + if (_element != null) + { + _element.Tap += ElementOnTap; + _element.DoubleTap += ElementOnDoubleTap; + _element.ManipulationDelta += OnManipulationDelta; + _element.ManipulationCompleted += OnManipulationCompleted; + } + + UpdateNativeControl(); + } + } + + public TModel Model + { + get { return _model; } + set + { + if (_model == value) + return; + + if (_model != null) + { + _model.BatchCommitted -= HandleRedrawNeeded; + _model.PropertyChanged -= HandlePropertyChanged; + } + + _model = value; + + if (_model != null) + { + _model.BatchCommitted += HandleRedrawNeeded; + _model.PropertyChanged += HandlePropertyChanged; + } + + UpdateNativeControl(); + } + } + + public override void Dispose() + { + if (_disposed) + return; + _disposed = true; + + if (_element != null) + { + _element.Tap -= ElementOnTap; + _element.DoubleTap -= ElementOnDoubleTap; + _element.ManipulationDelta -= OnManipulationDelta; + _element.ManipulationCompleted -= OnManipulationCompleted; + } + + if (_model != null) + { + _model.BatchCommitted -= HandleRedrawNeeded; + _model.PropertyChanged -= HandlePropertyChanged; + } + + Child = null; + Model = null; + Element = null; + } + + protected virtual void HandlePropertyChanged(object sender, PropertyChangedEventArgs e) + { + if (Model.Batched) + { + if (e.PropertyName == VisualElement.XProperty.PropertyName || e.PropertyName == VisualElement.YProperty.PropertyName || e.PropertyName == VisualElement.WidthProperty.PropertyName || + e.PropertyName == VisualElement.HeightProperty.PropertyName) + _invalidateArrangeNeeded = true; + return; + } + + if (e.PropertyName == VisualElement.XProperty.PropertyName || e.PropertyName == VisualElement.YProperty.PropertyName || e.PropertyName == VisualElement.WidthProperty.PropertyName || + e.PropertyName == VisualElement.HeightProperty.PropertyName) + MaybeInvalidate(); + else if (e.PropertyName == VisualElement.AnchorXProperty.PropertyName || e.PropertyName == VisualElement.AnchorYProperty.PropertyName) + UpdateScaleAndRotation(Model, Element); + else if (e.PropertyName == VisualElement.ScaleProperty.PropertyName) + UpdateScaleAndRotation(Model, Element); + else if (e.PropertyName == VisualElement.TranslationXProperty.PropertyName || e.PropertyName == VisualElement.TranslationYProperty.PropertyName || + e.PropertyName == VisualElement.RotationProperty.PropertyName || e.PropertyName == VisualElement.RotationXProperty.PropertyName || e.PropertyName == VisualElement.RotationYProperty.PropertyName) + UpdateRotation(Model, Element); + else if (e.PropertyName == VisualElement.IsVisibleProperty.PropertyName) + UpdateVisibility(Model, Element); + else if (e.PropertyName == VisualElement.OpacityProperty.PropertyName) + UpdateOpacity(Model, Element); + else if (e.PropertyName == VisualElement.InputTransparentProperty.PropertyName) + UpdateInputTransparent(Model, Element); + } + + protected virtual void UpdateNativeControl() + { + if (Model == null || Element == null) + return; + + UpdateOpacity(_model, _element); + UpdateScaleAndRotation(_model, _element); + UpdateInputTransparent(_model, _element); + + if (_invalidateArrangeNeeded) + MaybeInvalidate(); + _invalidateArrangeNeeded = false; + + UpdateTouchFrameReportedEvent(_model); + + OnUpdated(); + } + + void ElementOnDoubleTap(object sender, GestureEventArgs gestureEventArgs) + { + var view = Model as View; + if (view == null) + return; + + foreach (TapGestureRecognizer gestureRecognizer in + view.GestureRecognizers.OfType<TapGestureRecognizer>().Where(g => g.NumberOfTapsRequired == 2)) + { + gestureRecognizer.SendTapped(view); + gestureEventArgs.Handled = true; + } + } + + void ElementOnTap(object sender, GestureEventArgs gestureEventArgs) + { + var view = Model as View; + if (view == null) + return; + + foreach (TapGestureRecognizer gestureRecognizer in + view.GestureRecognizers.OfType<TapGestureRecognizer>().Where(g => g.NumberOfTapsRequired == 1)) + { + gestureRecognizer.SendTapped(view); + gestureEventArgs.Handled = true; + } + } + + void HandlePan(ManipulationDeltaEventArgs e, View view) + { + foreach (PanGestureRecognizer recognizer in + view.GestureRecognizers.GetGesturesFor<PanGestureRecognizer>().Where(g => g.TouchPoints == _touchPoints)) + { + if (!_isPanning) + ((IPanGestureController)recognizer).SendPanStarted(view, Application.Current.PanGestureId); + + double totalX = 0; + double totalY = 0; + + // Translation and CumulativeManipulation will be 0 if we have more than one touch point because it thinks we're pinching, + // so we'll just go ahead and use the center point of the pinch gesture to figure out how much we're panning. + if (_touchPoints > 1 && e.PinchManipulation != null) + { + totalX = e.PinchManipulation.Current.Center.X - e.PinchManipulation.Original.Center.X; + totalY = e.PinchManipulation.Current.Center.Y - e.PinchManipulation.Original.Center.Y; + } + else + { + totalX = e.DeltaManipulation.Translation.X + e.CumulativeManipulation.Translation.X; + totalY = e.DeltaManipulation.Translation.Y + e.CumulativeManipulation.Translation.Y; + } + + ((IPanGestureController)recognizer).SendPan(view, totalX, totalY, Application.Current.PanGestureId); + _isPanning = true; + } + } + + void HandlePinch(ManipulationDeltaEventArgs e, View view) + { + if (e.PinchManipulation == null) + return; + + IEnumerable<PinchGestureRecognizer> pinchGestures = view.GestureRecognizers.GetGesturesFor<PinchGestureRecognizer>(); + System.Windows.Point translationPoint = e.ManipulationContainer.TransformToVisual(Element).Transform(e.PinchManipulation.Current.Center); + var scaleOriginPoint = new Point(translationPoint.X / view.Width, translationPoint.Y / view.Height); + foreach (var recognizer in pinchGestures) + { + if (!_isPinching) + ((IPinchGestureController)recognizer).SendPinchStarted(view, scaleOriginPoint); + ((IPinchGestureController)recognizer).SendPinch(view, e.PinchManipulation.DeltaScale, scaleOriginPoint); + } + _isPinching = true; + } + + void HandleRedrawNeeded(object sender, EventArgs e) + { + UpdateNativeControl(); + } + + void MaybeInvalidate() + { + if (Model.IsInNativeLayout) + return; + var parent = (FrameworkElement)Element.Parent; + parent?.InvalidateMeasure(); + Element.InvalidateMeasure(); + } + + void OnManipulationCompleted(object sender, ManipulationCompletedEventArgs e) + { + var view = Model as View; + if (view == null) + return; + + IEnumerable pinchGestures = view.GestureRecognizers.GetGesturesFor<PinchGestureRecognizer>(); + foreach (var recognizer in pinchGestures) + ((IPinchGestureController)recognizer).SendPinchEnded(view); + _isPinching = false; + + IEnumerable<PanGestureRecognizer> panGestures = view.GestureRecognizers.GetGesturesFor<PanGestureRecognizer>().Where(g => g.TouchPoints == _touchPoints); + foreach (PanGestureRecognizer recognizer in panGestures) + ((IPanGestureController)recognizer).SendPanCompleted(view, Application.Current.PanGestureId); + Application.Current.PanGestureId++; + _isPanning = false; + } + + void OnManipulationDelta(object sender, ManipulationDeltaEventArgs e) + { + var view = Model as View; + if (view == null) + return; + + HandlePinch(e, view); + + HandlePan(e, view); + } + + void Touch_FrameReported(object sender, TouchFrameEventArgs e) + { + _touchPoints = e.GetTouchPoints(Child).Count; + } + + static void UpdateInputTransparent(VisualElement view, FrameworkElement frameworkElement) + { + frameworkElement.IsHitTestVisible = !view.InputTransparent; + } + + static void UpdateOpacity(VisualElement view, FrameworkElement frameworkElement) + { + frameworkElement.Opacity = view.Opacity; + } + + static void UpdateRotation(VisualElement view, FrameworkElement frameworkElement) + { + double anchorX = view.AnchorX; + double anchorY = view.AnchorY; + double rotationX = view.RotationX; + double rotationY = view.RotationY; + double rotation = view.Rotation; + double translationX = view.TranslationX; + double translationY = view.TranslationY; + double scale = view.Scale; + + frameworkElement.Projection = new PlaneProjection + { + CenterOfRotationX = anchorX, + CenterOfRotationY = anchorY, + GlobalOffsetX = translationX / scale, + GlobalOffsetY = translationY / scale, + RotationX = -rotationX, + RotationY = -rotationY, + RotationZ = -rotation + }; + } + + static void UpdateScaleAndRotation(VisualElement view, FrameworkElement frameworkElement) + { + double anchorX = view.AnchorX; + double anchorY = view.AnchorY; + double scale = view.Scale; + frameworkElement.RenderTransformOrigin = new System.Windows.Point(anchorX, anchorY); + frameworkElement.RenderTransform = new ScaleTransform { ScaleX = scale, ScaleY = scale }; + + UpdateRotation(view, frameworkElement); + } + + void UpdateTouchFrameReportedEvent(VisualElement model) + { + if (_touchFrameReportedEventSet) + return; + + Touch.FrameReported -= Touch_FrameReported; + _touchFrameReportedEventSet = false; + + var view = model as View; + if (view == null) + return; + + if (!view.GestureRecognizers.GetGesturesFor<PanGestureRecognizer>().Any(g => g.TouchPoints > 1)) + return; + + Touch.FrameReported += Touch_FrameReported; + _touchFrameReportedEventSet = true; + } + + static void UpdateVisibility(VisualElement view, FrameworkElement frameworkElement) + { + frameworkElement.Visibility = view.IsVisible ? Visibility.Visible : Visibility.Collapsed; + } + } +}
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