refresh method
Manually calls the compute update callback (given by the constructor) and store the result on cache.
After refresh, the cache is considered valid.
The returned value should be the new cache value.
See also:
- CachedValue.refresh for the general behavior of refresh.
Implementation
@override
CacheContentType refresh() {
_value = _computeCache();
_isValid = true;
return _value;
}