Duration constructor
Creates a new Duration object whose value is the sum of all individual parts.
Individual parts can be larger than the next-bigger unit.
For example, hours
can be greater than 23.
All individual parts are allowed to be negative. All arguments are 0 by default.
Implementation
const Duration(
{int days: 0,
int hours: 0,
int minutes: 0,
int seconds: 0,
int milliseconds: 0,
int microseconds: 0})
: this._microseconds(microsecondsPerDay * days +
microsecondsPerHour * hours +
microsecondsPerMinute * minutes +
microsecondsPerSecond * seconds +
microsecondsPerMillisecond * milliseconds +
microseconds);