insertInHashmap function
Implementation
void insertInHashmap(HashMap map, int index) {
// re-order hashmap
var newMap = HashMap();
if (map.containsKey(index)) {
// build new map
var keys = map.keys.toList(growable: false);
for (var key in keys) {
// define key
var k = key < index ? key : key + 1;
newMap[k] = map[key]!;
}
// add new entries back into original map
map.clear();
for (var entry in newMap.entries) {
map[entry.key] = entry.value;
}
}
}