public void SetValue(T param)
{
if (param == Value)
{
return;
}
var holder = GetHolder(param);
var old_value = holderedValue;
var new_value = holder;
var cmd = new Command.DelegateCommand(
() =>
{
holderedValue = new_value;
},
() =>
{
holderedValue = old_value;
});
Command.CommandManager.Execute(cmd);
}