using System.Threading.Tasks; using Xamarin.Forms.Platform; namespace Xamarin.Forms { [RenderWith(typeof(_ProgressBarRenderer))] public class ProgressBar : View { public static readonly BindableProperty ProgressProperty = BindableProperty.Create("Progress", typeof(double), typeof(ProgressBar), 0d, coerceValue: (bo, v) => ((double)v).Clamp(0, 1)); public double Progress { get { return (double)GetValue(ProgressProperty); } set { SetValue(ProgressProperty, value); } } public Task ProgressTo(double value, uint length, Easing easing) { var tcs = new TaskCompletionSource(); this.Animate("Progress", d => Progress = d, Progress, value, length: length, easing: easing, finished: (d, finished) => tcs.SetResult(finished)); return tcs.Task; } } }