Compiling to JavaScript

It is great that we have our enhanced text editor application running in Dartium, but that is not what most web users have installed. What if I want to use it in my daily-driver web browser; for example, Firefox or Internet Explorer?

In order to run on the entire modern Web, Dart code can be compiled via a tool called dart2js (written in Dart) to high quality and performance JavaScript. This can be run as a pub command:

pub build --mode=release

We first encountered this tool when we toured the SDK's command-line tools in the previous chapter. For easy use during development, it is accessible from WebStorm.

In WebStorm's Project tab, right-click on the pubspec.yaml file, and select Pub: Build .... The mode option is then presented for Release or Debug—for production, choose Release. This creates a folder called build with the JavaScript version of the program. This can be served by any web server and used from any modern browser:

It may be surprising, if text was entered in the Dartium version, that the editor is blank when run from a regular browser. One downside of using local storage is that each web browser has its own independent storage and the user will have to re-enter data if they switch browsers, even if they are on the same computer.