How to modify binded value in MVVM Cross - ios

Question

I have a model from my json in a Xamarin MVVM app(ios). I want to add the "%" after the value? in the list "coinmarketcaplist" contains the value 24h_change, this is the value I want to add a % to, it's a string. I know that I should use a getter for it, but I don't know how since I'm fairly new to this. below is my ViewModel code:
public class CMCTableViewModel : MvxViewModel
{
protected readonly ICoinMarketCapService _coinMarketCapService;
public CMCTableViewModel(ICoinMarketCapService coinMarketCapService)
{
_coinMarketCapService = coinMarketCapService;
LoadData();
}
private List<CoinMarketCapModel> _coinMarketCapModelList;
public List<CoinMarketCapModel> CoinMarketCapModelList
{
get
{
return _coinMarketCapModelList;
}
set
{
_coinMarketCapModelList = value;
RaisePropertyChanged(() => CoinMarketCapModelList);
}
}
public async void LoadData()
{
CoinMarketCapModelList = await _coinMarketCapService.GetCoins();
}
}
TableCell:
internal static readonly NSString Identifier = new NSString("CMCTableCell");
public override void LayoutSubviews()
{
base.LayoutSubviews();
MvxFluentBindingDescriptionSet<CMCTableCell, CoinMarketCapModel> set = new MvxFluentBindingDescriptionSet<CMCTableCell, CoinMarketCapModel>(this);
set.Bind(lblName).To(res => res.Name);
set.Bind(lblPrice).To(res => res.percent_change_24h);
set.Bind(imgCoin)
.For(img => img.Image)
.To(res => res.image)
.WithConversion<StringToImageConverter>();
set.Apply();
}
}
edit: added cellview

Answer 1

Use a converter in your binding:
1) Define converter:
public class StringFormatValueConverter : MvxValueConverter
{
public override object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
{
if (value == null)
return null;
if (parameter == null)
return value;
return string.Format(parameter.ToString(), value);
}
}
2) Use it in your binding:
set.Bind(lblPrice).To(res => res.percent_change_24h).WithConversion<StringFormatValueConverter>("{0} %");
You can use this converter when you want to modify the input string by adding something around it, for example unit or currency