JavaScript

JavaScript is a scripting feature in Tasker that allows users to execute JavaScript code within tasks and scenes. Through JavaScript, users can access Tasker variables, call Tasker actions as functions, manipulate scenes, process data, interact with web services, and create advanced automation logic.

Tasker's JavaScript support is available through the JavaScriptlet and JavaScript actions, as well as within WebView scene elements.

Overview

JavaScript provides an alternative programming environment within Tasker. Unlike traditional Tasker actions, JavaScript allows users to write custom logic using variables, conditions, loops, functions, and objects.

Tasker integrates JavaScript directly with its automation engine, enabling Tasker variables and actions to be accessed from JavaScript code.

Components

JavaScriptlet

The JavaScriptlet action allows JavaScript code to be written directly inside a Tasker task.

JavaScriptlets execute sequentially alongside other Tasker actions and can read and modify Tasker variables.

JavaScript

The JavaScript action executes JavaScript code stored in an external file.

This allows larger scripts to be maintained separately from tasks and edited using external tools.

WebView JavaScript

JavaScript can also be embedded within WebView scene elements.

This allows users to create interactive user interfaces using HTML, CSS, and JavaScript.

Example:

<h1 onclick="setWifi(false)">

    Turn Off Wi-Fi

</h1>

Variables

Local Variables

Tasker local variables are automatically available in JavaScript without the % prefix.

Example:

Tasker:

%name

JavaScript:

flash(name);

Changes made to local variables within JavaScript are reflected in subsequent Tasker actions.

Global Variables

Global variables must be accessed using helper functions.

Example:

var wifi = global("WIFI");

Setting a global variable:

setGlobal("MyVar", "Hello");

Arrays

Tasker arrays are automatically converted to JavaScript arrays and vice versa.

Example:

Tasker:

%arr(1)

JavaScript equivalent:

arr[0]

Important differences:

• JavaScript arrays begin at index 0.

• Tasker arrays begin at index 1.

• JavaScript uses square brackets.

• Tasker uses parentheses.

Built-In Functions

Tasker exposes many actions as JavaScript functions.

Examples include:

Device Control

setWifi(true);

setBT(true);

setAirplaneMode(false);

Notifications

flash("Task Complete");

flashLong("Automation Finished");

Media Control

mediaControl("play");

mediaControl("pause");

Phone Functions

call("5551234567", true);

sendSMS("5551234567", "Hello");

File Operations

writeFile("/sdcard/test.txt", "Hello World");

Scene Control

showScene("Dashboard");

hideScene("Dashboard");

Built-In Categories

Tasker's JavaScript functions cover a wide range of automation capabilities:

• Audio control

• Bluetooth management

• Wi-Fi management

• Mobile data control

• File operations

• Notifications

• Telephony

• Media playback

• Scene manipulation

• Image processing

• Location services

• Device settings

• Task execution

• Intent sending

• Clipboard management

Scene Integration

JavaScript is commonly used with Tasker Scenes.

Functions are available to:

• Change element text

• Change colors

• Move elements

• Show or hide elements

• Update interfaces dynamically

Example:

elemText("Dashboard", "Status", "repl", "Connected");

Web Services

JavaScript supports standard browser technologies, including:

• JSON

• XMLHttpRequest

• External JavaScript libraries

This allows communication with APIs and web services directly from Tasker.

Execution Model

Only one JavaScript script executes at a time within Tasker.

Scripts execute alongside normal Tasker actions and can interact with running tasks and profiles.

When using asynchronous functions such as:

setTimeout(...)

the Auto Exit option should typically be disabled, and the script must manually call:

exit();

to allow Tasker to continue execution.

Common Uses

JavaScript is commonly used for:

• Data processing

• API communication

• JSON parsing

• Web service integration

• Dynamic user interfaces

• Complex calculations

• Scene interaction

• File management

• Device control

• Custom automation logic

JavaScript vs Java Code

Feature

JavaScript

Java Code

Language

JavaScript

Java (BeanShell)

Built-in Tasker Functions

Yes

Yes

Android API Access

Limited

Extensive

Web APIs

Yes

Limited

Scene Integration

Excellent

Limited

HTML/WebView Support

Yes

No

JSON Handling

Excellent

Good

Android Framework Access

Limited

Full

Limitations

• Only one JavaScript script may execute at a time.

• Global arrays are not supported.

• Some built-in functions require root access.

• JavaScript actions cannot directly access all Android APIs.

• Settings changed through JavaScript are not automatically restored when a profile exits.

Legacy

JavaScript has been part of Tasker since its early releases and remains one of the platform's most powerful scripting options. It allows users to extend Tasker's capabilities beyond standard actions while remaining easier to learn than Android's Java APIs.

See Also

• Java

• Java Function

• Java Code

• Scenes

• Variables

• Tasks

• WebView

• Tasker AI Generator