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Diffstat (limited to 'Xamarin.Forms.Core/ViewExtensions.cs')
| -rw-r--r-- | Xamarin.Forms.Core/ViewExtensions.cs | 197 |
1 files changed, 197 insertions, 0 deletions
diff --git a/Xamarin.Forms.Core/ViewExtensions.cs b/Xamarin.Forms.Core/ViewExtensions.cs new file mode 100644 index 00000000..14a70868 --- /dev/null +++ b/Xamarin.Forms.Core/ViewExtensions.cs @@ -0,0 +1,197 @@ +using System; +using System.Threading.Tasks; + +namespace Xamarin.Forms +{ + public static class ViewExtensions + { + public static void CancelAnimations(VisualElement view) + { + if (view == null) + throw new ArgumentNullException("view"); + view.AbortAnimation("LayoutTo"); + view.AbortAnimation("TranslateTo"); + view.AbortAnimation("RotateTo"); + view.AbortAnimation("RotateYTo"); + view.AbortAnimation("RotateXTo"); + view.AbortAnimation("ScaleTo"); + view.AbortAnimation("FadeTo"); + view.AbortAnimation("SizeTo"); + } + + public static Task<bool> FadeTo(this VisualElement view, double opacity, uint length = 250, Easing easing = null) + { + if (view == null) + throw new ArgumentNullException("view"); + if (easing == null) + easing = Easing.Linear; + + var tcs = new TaskCompletionSource<bool>(); + var weakView = new WeakReference<VisualElement>(view); + Action<double> fade = f => + { + VisualElement v; + if (weakView.TryGetTarget(out v)) + v.Opacity = f; + }; + + new Animation(fade, view.Opacity, opacity, easing).Commit(view, "FadeTo", 16, length, finished: (f, a) => tcs.SetResult(a)); + + return tcs.Task; + } + + public static Task<bool> LayoutTo(this VisualElement view, Rectangle bounds, uint length = 250, Easing easing = null) + { + if (view == null) + throw new ArgumentNullException("view"); + if (easing == null) + easing = Easing.Linear; + + var tcs = new TaskCompletionSource<bool>(); + Rectangle start = view.Bounds; + Func<double, Rectangle> computeBounds = progress => + { + double x = start.X + (bounds.X - start.X) * progress; + double y = start.Y + (bounds.Y - start.Y) * progress; + double w = start.Width + (bounds.Width - start.Width) * progress; + double h = start.Height + (bounds.Height - start.Height) * progress; + + return new Rectangle(x, y, w, h); + }; + var weakView = new WeakReference<VisualElement>(view); + Action<double> layout = f => + { + VisualElement v; + if (weakView.TryGetTarget(out v)) + v.Layout(computeBounds(f)); + }; + new Animation(layout, 0, 1, easing).Commit(view, "LayoutTo", 16, length, finished: (f, a) => tcs.SetResult(a)); + + return tcs.Task; + } + + public static Task<bool> RelRotateTo(this VisualElement view, double drotation, uint length = 250, Easing easing = null) + { + if (view == null) + throw new ArgumentNullException("view"); + return view.RotateTo(view.Rotation + drotation, length, easing); + } + + public static Task<bool> RelScaleTo(this VisualElement view, double dscale, uint length = 250, Easing easing = null) + { + if (view == null) + throw new ArgumentNullException("view"); + return view.ScaleTo(view.Scale + dscale, length, easing); + } + + public static Task<bool> RotateTo(this VisualElement view, double rotation, uint length = 250, Easing easing = null) + { + if (view == null) + throw new ArgumentNullException("view"); + if (easing == null) + easing = Easing.Linear; + + var tcs = new TaskCompletionSource<bool>(); + var weakView = new WeakReference<VisualElement>(view); + Action<double> rotate = f => + { + VisualElement v; + if (weakView.TryGetTarget(out v)) + v.Rotation = f; + }; + + new Animation(rotate, view.Rotation, rotation, easing).Commit(view, "RotateTo", 16, length, finished: (f, a) => tcs.SetResult(a)); + + return tcs.Task; + } + + public static Task<bool> RotateXTo(this VisualElement view, double rotation, uint length = 250, Easing easing = null) + { + if (view == null) + throw new ArgumentNullException("view"); + if (easing == null) + easing = Easing.Linear; + + var tcs = new TaskCompletionSource<bool>(); + var weakView = new WeakReference<VisualElement>(view); + Action<double> rotatex = f => + { + VisualElement v; + if (weakView.TryGetTarget(out v)) + v.RotationX = f; + }; + + new Animation(rotatex, view.RotationX, rotation, easing).Commit(view, "RotateXTo", 16, length, finished: (f, a) => tcs.SetResult(a)); + + return tcs.Task; + } + + public static Task<bool> RotateYTo(this VisualElement view, double rotation, uint length = 250, Easing easing = null) + { + if (view == null) + throw new ArgumentNullException("view"); + if (easing == null) + easing = Easing.Linear; + + var tcs = new TaskCompletionSource<bool>(); + var weakView = new WeakReference<VisualElement>(view); + Action<double> rotatey = f => + { + VisualElement v; + if (weakView.TryGetTarget(out v)) + v.RotationY = f; + }; + + new Animation(rotatey, view.RotationY, rotation, easing).Commit(view, "RotateYTo", 16, length, finished: (f, a) => tcs.SetResult(a)); + + return tcs.Task; + } + + public static Task<bool> ScaleTo(this VisualElement view, double scale, uint length = 250, Easing easing = null) + { + if (view == null) + throw new ArgumentNullException("view"); + if (easing == null) + easing = Easing.Linear; + + var tcs = new TaskCompletionSource<bool>(); + var weakView = new WeakReference<VisualElement>(view); + Action<double> _scale = f => + { + VisualElement v; + if (weakView.TryGetTarget(out v)) + v.Scale = f; + }; + + new Animation(_scale, view.Scale, scale, easing).Commit(view, "ScaleTo", 16, length, finished: (f, a) => tcs.SetResult(a)); + + return tcs.Task; + } + + public static Task<bool> TranslateTo(this VisualElement view, double x, double y, uint length = 250, Easing easing = null) + { + if (view == null) + throw new ArgumentNullException("view"); + easing = easing ?? Easing.Linear; + + var tcs = new TaskCompletionSource<bool>(); + var weakView = new WeakReference<VisualElement>(view); + Action<double> translateX = f => + { + VisualElement v; + if (weakView.TryGetTarget(out v)) + v.TranslationX = f; + }; + Action<double> translateY = f => + { + VisualElement v; + if (weakView.TryGetTarget(out v)) + v.TranslationY = f; + }; + new Animation { { 0, 1, new Animation(translateX, view.TranslationX, x) }, { 0, 1, new Animation(translateY, view.TranslationY, y) } }.Commit(view, "TranslateTo", 16, length, easing, + (f, a) => tcs.SetResult(a)); + + return tcs.Task; + } + } +}
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