Timer abstract class

A count-down timer that can be configured to fire once or repeatedly.

The timer counts down from the specified duration to 0. When the timer reaches 0, the timer invokes the specified callback function. Use a periodic timer to repeatedly count down the same interval.

A negative duration is treated the same as a duration of 0. If the duration is statically known to be 0, consider using run.

Frequently the duration is either a constant or computed as in the following example (taking advantage of the multiplication operator of the Duration class):

const TIMEOUT = const Duration(seconds: 3);
const ms = const Duration(milliseconds: 1);

startTimeout([int milliseconds]) {
  var duration = milliseconds == null ? TIMEOUT : ms * milliseconds;
  return new Timer(duration, handleTimeout);
}
...
void handleTimeout() {  // callback function
  ...
}

Note: If Dart code using Timer is compiled to JavaScript, the finest granularity available in the browser is 4 milliseconds.

See Stopwatch for measuring elapsed time.

Static Methods

run(void callback()) → void

Runs the given callback asynchronously as soon as possible.

Constructors

Timer(Duration duration, void callback())
factory

Creates a new timer.

Timer.periodic(Duration duration, void callback(Timer timer))
factory

Creates a new repeating timer.

Properties

isActivebool
read-only

Returns whether the timer is still active.

hashCodeint
read-only, inherited

The hash code for this object.

runtimeTypeType
read-only, inherited

A representation of the runtime type of the object.

Operators

operator ==(other) → bool
inherited

The equality operator.

Methods

cancel() → void

Cancels the timer.

noSuchMethod(Invocation invocation) → dynamic
inherited

Invoked when a non-existent method or property is accessed.

toString() → String
inherited

Returns a string representation of this object.

© 2012 the Dart project authors
Licensed under the Creative Commons Attribution-ShareAlike License v4.0.
https://api.dartlang.org/stable/1.24.3/dart-async/Timer-class.html