| // Copyright (c) 2012, the Dart project authors. Please see the AUTHORS file |
| // for details. All rights reserved. Use of this source code is governed by a |
| // BSD-style license that can be found in the LICENSE file. |
| |
| part of dart.async; |
| |
| abstract class Timer { |
| |
| /** |
| * Creates a new timer. |
| * |
| * The [callback] callback is invoked after the given [duration]. |
| * A negative duration is treated similar to 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); |
| * } |
| * |
| * Note: If Dart code using Timer is compiled to JavaScript, the finest |
| * granularity available in the browser is 4 milliseconds. |
| */ |
| factory Timer(Duration duration, void callback()) { |
| return _Zone.current.createTimer(duration, callback); |
| } |
| |
| /** |
| * Creates a new repeating timer. |
| * |
| * The [callback] is invoked repeatedly with [duration] intervals until |
| * canceled. A negative duration is treated similar to a duration of 0. |
| */ |
| factory Timer.periodic(Duration duration, |
| void callback(Timer timer)) { |
| return _Zone.current.createPeriodicTimer(duration, callback); |
| } |
| |
| /** |
| * Runs the given [callback] asynchronously as soon as possible. |
| * |
| * This function is equivalent to `new Timer(Duration.ZERO, callback)`. |
| */ |
| static void run(void callback()) { |
| new Timer(Duration.ZERO, callback); |
| } |
| |
| /** |
| * Cancels the timer. |
| */ |
| void cancel(); |
| |
| /** |
| * Returns whether the timer is still active. |
| * |
| * A non-periodic timer is active if the callback has not been executed, |
| * and the timer has not been canceled. |
| * |
| * A periodic timer is active if it has not been canceled. |
| */ |
| bool get isActive; |
| } |
| |
| external Timer _createTimer(Duration duration, void callback()); |
| external Timer _createPeriodicTimer(Duration duration, |
| void callback(Timer timer)); |