onChangeEx method
Implementation
void onChangeEx(String value) {
var result = widget.items?.indexWhere(
(e) =>
((e[widget.nameKey] is Map)
? e[widget.nameKey][widget.nameMapKey]
: e[widget.nameKey]) ==
value,
);
if (result != -1) {
widget.onChanged?.call(widget.items?[result ?? 0] ?? {});
} else {
widget.onChanged?.call({});
}
}