setIndex method
Implementation
void setIndex(BuildContext context, int index) {
assert(index >= 0);
_init(context);
_materialController?.index = index;
_cupertinoController?.index = index;
}
void setIndex(BuildContext context, int index) {
assert(index >= 0);
_init(context);
_materialController?.index = index;
_cupertinoController?.index = index;
}