Pattern Notation

The pattern() helper converts a compact notation string into a HapticEvent[] array that can be passed to triggerPattern() or used as a fallback in playHaptic().

Character reference

Char	Meaning	Effect
o	Soft transient	Intensity 0.4, sharpness 0.4; advances cursor 100 ms
O	Strong transient	Intensity 1.0, sharpness 0.8; advances cursor 100 ms
.	Short gap	+150 ms
-	Medium gap	+400 ms
=	Long gap	+1000 ms

Gap characters add to the current cursor position. Consecutive haptic events (OOO) are implicitly 100 ms apart so the hardware renders each as a distinct pulse.

Examples

import { pattern } from "react-native-haptic-feedback";

pattern("oO"); // two pulses: soft then strong
pattern("O.O"); // two strong pulses, 250 ms apart
pattern("oO--oO"); // heartbeat: double-pulse, pause, double-pulse
pattern("o.o.o"); // rapid triple tap

Visualizing timing

notation  →  o    O    .    O
cursor    →  0   100  200  350  (ms)

Notation	Events	Total duration
oO	2	~100 ms
O.O	2	~250 ms
oO--oO	4	~1 100 ms
o.o.o	3	~500 ms
o-O=o	3	~1 600 ms

Compile-time validation

When you pass a string literal, TypeScript rejects invalid characters at compile time:

pattern("oO.O"); // ✓ valid
pattern("oXO"); // ✗ TypeScript error: Argument of type 'string' is not assignable
//   to parameter of type 'never'

Runtime variables are allowed through without type errors; invalid characters throw a TypeError at runtime instead:

const s: string = getUserInput();
pattern(s); // compiles fine; throws TypeError if s contains bad chars

Runtime validation

try {
  const events = pattern(userInput);
  HapticFeedback.triggerPattern(events);
} catch (e) {
  if (e instanceof TypeError) {
    console.warn(e.message);
    // "pattern(): invalid character "x" at position 2. Allowed characters are: o O . - ="
  }
}

Built-in presets

Six named presets are available as pre-computed HapticEvent[] arrays:

import { Patterns } from "react-native-haptic-feedback";

HapticFeedback.triggerPattern(Patterns.success);
HapticFeedback.triggerPattern(Patterns.error);

Name	Notation	Description
success	oO.O	Soft then strong — "good job" feel
error	OO.OO	Two heavy hits — clear error signal
warning	O.O	Single medium pulse — gentle alert
heartbeat	oO--oO	Double heartbeat rhythm
tripleClick	o.o.o	Rapid triple tap
notification	o-O=o	Long rise-and-fall

See the full Patterns API reference.