PhpStorm provides a common procedure and user interface for creating File Watchers of all types. The only difference is in the predefined templates you choose in each case.
- To start creating a File Watcher, open the Project Settings and click File Watchers. The File Watchers page that opens, shows the list of File Watchers that are already configured in the project.
-
Click the Add button
or press Alt+InsertAlt+Insert
and choose the Dart2JS predefined template from the pop-up list.
-
In the Program text box, specify the path to the dart2js.bat file. Type the path manually or click the Browse button
and choose the file location in the dialog box that opens.
The default location is <Dart home>/dart-sdk/bin/dart2js.bar.
- Proceed as described on page Using File Watchers.
Transpiling the Dart code
When you open a Dart file, PhpStorm checks whether an applicable file watcher is available in the current project. If such file watcher is configured but disabled, PhpStorm displays a pop-up window that informs you about the configured file watcher and suggests to enable it.
If an applicable file watcher is configured and enabled in the current project, PhpStorm starts it automatically upon the event specified in the New Watcher dialog.
- If the Immediate file synchronization check box is selected, the File Watcher is invoked as soon as any changes are made to the source code.
- If the Immediate file synchronization check box is cleared, the File Watcher is started upon save (, ) or when you move focus from PhpStorm (upon frame deactivation).
The transpiler stores the generated output in a separate file. The file has the name of the source Dart file and the extension js or js.map depending on the transpiler type. The location of the generated files is defined in the Output Paths text box of the New Watcher dialog. Based on this setting, PhpStorm detects transpiler output.

tool which is a part of the Dart SDK.
The