Index: packages/async/lib/src/restartable_timer.dart |
diff --git a/packages/async/lib/src/restartable_timer.dart b/packages/async/lib/src/restartable_timer.dart |
new file mode 100644 |
index 0000000000000000000000000000000000000000..05196d2873675ef9ad222be92aadf5cc74ee9ce6 |
--- /dev/null |
+++ b/packages/async/lib/src/restartable_timer.dart |
@@ -0,0 +1,48 @@ |
+// Copyright (c) 2015, 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. |
+ |
+library async.restartable_timer; |
+ |
+import 'dart:async'; |
+ |
+/// A non-periodic timer that can be restarted any number of times. |
+/// |
+/// Once restarted (via [reset]), the timer counts down from its original |
+/// duration again. |
+class RestartableTimer implements Timer { |
+ /// The duration of the timer. |
+ final Duration _duration; |
+ |
+ /// The callback to call when the timer fires. |
+ final ZoneCallback _callback; |
+ |
+ /// The timer for the current or most recent countdown. |
+ /// |
+ /// This timer is canceled and overwritten every time this [RestartableTimer] |
+ /// is reset. |
+ Timer _timer; |
+ |
+ /// Creates a new timer. |
+ /// |
+ /// The [callback] function is invoked after the given [duration]. Unlike a |
+ /// normal non-periodic [Timer], [callback] may be called more than once. |
+ RestartableTimer(this._duration, this._callback) { |
+ _timer = new Timer(_duration, _callback); |
+ } |
+ |
+ bool get isActive => _timer.isActive; |
+ |
+ /// Restarts the timer so that it counts down from its original duration |
+ /// again. |
+ /// |
+ /// This restarts the timer even if it has already fired or has been canceled. |
+ void reset() { |
+ _timer.cancel(); |
+ _timer = new Timer(_duration, _callback); |
+ } |
+ |
+ void cancel() { |
+ _timer.cancel(); |
+ } |
+} |