void ISupportsStartFinish.Finish() {
            if(model == null)
                return;

            this.model.StopMarketSimulation();
            this.model = null;
        }
        async void BindData()
        {
            MainPageViewModel model = await LoadData();

            BindingContext = model;
        }
        async void BindData()
        {
            this.model = await LoadData();

            BindingContext = model;
        }
 async void BindData() {
     this.model = await LoadData();
     BindingContext = model;
 }