ShowProgressAttribute

ShowProgressAttribute.cs

    public class ShowProgressAttribute :MethodInterceptionAspect
    {
        private string _title;
        public ShowProgressAttribute(string title)
        {
            _title = title;
        }

        public override async Task OnInvokeAsync(MethodInterceptionArgs args)
        {
            var arguments = args.Arguments.ToList();
            var progressArg = args.Method.GetParameters()
                .FirstOrDefault(a => typeof(IProgress<int>).IsAssignableFrom(a.ParameterType));
            if (progressArg != null)
            {
                var progress=new Progress<int>();
                args.Arguments.SetArgument(args.Method.GetParameters().ToList().IndexOf(progressArg), progress);

                var cancellationToken = new CancellationTokenSource();

                args.Arguments.SetArgument(arguments.IndexOf(args.Arguments.FirstOrDefault(a => a is CancellationToken)),cancellationToken.Token);

                using (var dlg = UserDialogs.Instance.Progress(_title.Localize(), () => cancellationToken.Cancel(), null, true,  maskType: MaskType.Black))
                {
                    progress.ProgressChanged += (sender, i) => {  Device.BeginInvokeOnMainThread((() => { dlg.PercentComplete = i; }); };
                    try
                    {
                        await args.ProceedAsync();
                    }
                    catch (Exception ex)
                    {

                        dlg.Hide();
                        dlg.Dispose();
                        throw ex;
                    }
                }
            }
            else
            {

                using (var dlg = UserDialogs.Instance.Loading(_title.Localize(), null, null, true,
                    maskType: MaskType.Black))
                {
                    try
                    {
                        await args.ProceedAsync();
                    }
                    catch (Exception ex)
                    {
                        dlg.Hide();
                        dlg.Dispose();
                        throw ex;
                    }
                }
              
            }

        }
       
    }