Timer class - dart:async library (original) (raw)

A countdown 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 Duration.zero. If the duration is statically known to be 0, consider using run.

void main() {
  Timer(const Duration(seconds: 5), handleTimeout);
}

void handleTimeout() {  // callback function
  // Do some work.
}

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

See also:

• Stopwatch for measuring elapsed time.

Annotations

• @vmIsolateUnsendable

Constructors

Timer(Duration duration, void callback())

Creates a new timer.

factory

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

Creates a new repeating timer.

factory

Properties

hashCode → int

The hash code for this object.

no setterinherited

isActive → bool

Returns whether the timer is still active.

no setter

runtimeType → Type

A representation of the runtime type of the object.

no setterinherited

tick → int

The number of durations preceding the most recent timer event.

no setter

Methods

cancel()→ void

Cancels the timer.

noSuchMethod(Invocation invocation)→ dynamic

Invoked when a nonexistent method or property is accessed.

inherited

toString()→ String

A string representation of this object.

inherited

Operators

operator ==(Object other)→ bool

The equality operator.

inherited

Static Methods

run(void callback())→ void

Runs the given callback asynchronously as soon as possible.