Using HTML5 input range Attribute with the Timer Class in Dart

Compliant with Dart Editor version 0.3.7r18717
Dart SDK version 0.3.7.6r18717
9:32 PM Wednesday, February 20, 2013
Blog entry at scribeGriff.com/studios
Comments: Update to M3.
Tags: Dart, Timer, HTML, DOM, Future

---

Update 20 February 2013: Update to M3 required removing dart:isolate library import and adding dart:async library. Both futures and the timer class are now in the async library.

Update 13 January 2013: Some minor changes as Dart marches towards version 2 of the html library:

addHtml(String)
innerHTML(String)

is now

appendHtml(String)
innerHtml(String)

and the use of futures has changed some:

void main() {
  var htmlExample = new HtmlInDart().createStyles();
  htmlExample
      ..then((htmlExample) => htmlExample.buildPage())
      ..then((htmlExample) => htmlExample.addListeners());
}

Finally, dart.js has been moved to pub so we now use a pubspec.yaml file and change the html file to:

<script src="packages/browser/dart.js"></script>

---

Update 15 October 2012: A lot has happened with the Dart programming language since I originally wrote this post last year. Perhaps the biggest change as it relates to this old blog post is that we now have a Timer class available on both the client and the server side through the dart:isolate library. But besides saying goodbye to both setInterval and clearInterval in our original example, we also incorporate some of the other really nice language features Dart has implemented in the past 10 months (M1 Language Changes), including:

• Method cascades
• Futures for asynchronous control
• No + for string concatenation
• Elements now have factory constructors:

so even though this still works:

DivElement myDiv1 = new Element.tag("div");

you can now just do this:

var myDiv1 = new DivElement();

This is just to name just a few of the changes. The post itself has been updated although the intent remains simply to illustrate how one could do a variety of assorted tasks in Dart and not to suggest a specific way of doing things.

Although not absolutely necessary for this example, we now use futures to build this simple application:

void main() {
  var htmlExample = new HtmlInDart().createStyles()
    .chain((HtmlInDart htmlExample) => htmlExample.buildPage())
    .chain((HtmlInDart htmlExample) => htmlExample.addListeners());
}