public override Java.Lang.ICharSequence FilterFormatted(Java.Lang.ICharSequence source, int start, int end, ISpanned dest, int dstart, int dend)
{
for (var x = start; x < end; x++)
{
if (char.IsUpper(source.ElementAt(x)))
{
var v = new char[end - start];
TextUtils.GetChars(source.ToString(), start, end, v, 0);
var s = new string(v).ToLower(CultureInfo.InvariantCulture);
if (source is ISpanned sourceSpanned)
{
var sp = new SpannableString(s);
TextUtils.CopySpansFrom(sourceSpanned, start, end, null, sp, 0);
return(sp);
}
else
{
return(new Java.Lang.String(s));
}
}
}
return(null);
}