How to declare a function callback that accepts multiple parameters in Dart/Flutter?
Variables of type Function can be declared as follows:
void main() { void Function(int) setVal1; void Function(int, int) setVal2; setVal1 = (int i) => print('$i'); setVal2 = (int i, int j) => print('$i, $j'); final String Function(int, int, [double]) setVal3 = (int i, int j, [double k]) => '$i, $j, $k'; final i = 0; final j = 1; final double k = 2.0; setVal1(i); setVal2(i, j); print(setVal3(i, j)); print(setVal3(i, j, k));}