TinyGesture.js

Very small gesture recognizer for JavaScript. Swipe, pan, tap, doubletap, longpress, pinch, and rotate.

Installation

``sh
npm install --save tinygesture
`

- If you're upgrading from v2, the diagonalLimit option has changed meaning and there are new events for pinch and rotate. Also TS now exports ES2020 instead of ES6.
- If you're upgrading from v1, the location of the file has changed. It's now in a "dist" folder, hence the major version change.

Usage

$3

`js
import TinyGesture from 'tinygesture';

// Options object is optional. These are the defaults.
const options = {
// Used to calculate the threshold to consider a movement a swipe. it is
// passed type of 'x' or 'y'.
threshold: (type, self) =>
Math.max(
25,
Math.floor(
0.15 *
(type === 'x'
? window.innerWidth || document.body.clientWidth
: window.innerHeight || document.body.clientHeight),
),
),
// Minimum velocity the gesture must be moving when the gesture ends to be
// considered a swipe.
velocityThreshold: 10,
// Used to calculate the distance threshold to ignore the gestures velocity
// and always consider it a swipe.
disregardVelocityThreshold: (type, self) =>
Math.floor(0.5 * (type === 'x' ? self.element.clientWidth : self.element.clientHeight)),
// Point at which the pointer moved too much to consider it a tap or longpress
// gesture.
pressThreshold: 8,
// If true, swiping in a diagonal direction will fire both a horizontal and a
// vertical swipe.
// If false, whichever direction the pointer moved more will be the only swipe
// fired.
diagonalSwipes: false,
// The degree limit to consider a diagonal swipe when diagonalSwipes is true.
// It's calculated as 45deg±diagonalLimit.
diagonalLimit: 15,
// Listen to mouse events in addition to touch events. (For desktop support.)
mouseSupport: true,
};

const target = document.getElementById('target');
const gesture = new TinyGesture(target, options);
`

$3

`js
gesture.on('panstart', (event) => {
// Always the original mouse or touch event.
// This service uses passive listeners, so you can't call
// event.preventDefault() on any of the events.
event;
// The (screen) x coordinate of the start of the gesture.
gesture.touchStartX;
// The (screen) y coordinate of the start of the gesture.
gesture.touchStartY;
});
gesture.on('panmove', (event) => {
// Everything from panstart, and...

// The amount the gesture has moved in the x direction.
gesture.touchMoveX;
// The amount the gesture has moved in the y direction.
gesture.touchMoveY;
// The instantaneous velocity in the x direction.
gesture.velocityX;
// The instantaneous velocity in the y direction.
gesture.velocityY;
// Boolean, whether the gesture has passed the swiping threshold in the x
// direction.
gesture.swipingHorizontal;
// Boolean, whether the gesture has passed the swiping threshold in the y
// direction.
gesture.swipingVertical;
// Which direction the gesture has moved most. Prefixed with 'pre-' if the
// gesture hasn't passed the corresponding threshold.
// One of: ['horizontal', 'vertical', 'pre-horizontal', 'pre-vertical']
gesture.swipingDirection;
// To tell if the gesture is a left swipe, you can do something like this:
if (gesture.swipingDirection === 'horizontal' && gesture.touchMoveX < 0) {
alert('You are currently swiping left.');
}
});
gesture.on('panend', (event) => {
// Everything from panstart and panmove, and...

// The (screen) x coordinate of the end of the gesture.
gesture.touchEndX;
// The (screen) y coordinate of the end of the gesture.
gesture.touchEndY;

// Swipe events are fired depending on the touch end coordinates, so
// properties like swipingDirection may be incorrect at this point, since
// they're based on the last touch move coordinates.
});

gesture.on('swiperight', (event) => {
// The gesture was a right swipe.

// This will always be true for a right swipe.
gesture.swipedHorizontal;
// This will be true if diagonalSwipes is on and the gesture was diagonal
// enough to also be a vertical swipe.
gesture.swipedVertical;
});
gesture.on('swipeleft', (event) => {
// The gesture was a left swipe.

// This will always be true for a left swipe.
gesture.swipedHorizontal;
// This will be true if diagonalSwipes is on and the gesture was diagonal
// enough to also be a vertical swipe.
gesture.swipedVertical;
});
gesture.on('swipeup', (event) => {
// The gesture was an upward swipe.

// This will be true if diagonalSwipes is on and the gesture was diagonal
// enough to also be a horizontal swipe.
gesture.swipedHorizontal;
// This will always be true for an upward swipe.
gesture.swipedVertical;
});
gesture.on('swipedown', (event) => {
// The gesture was a downward swipe.

// This will be true if diagonalSwipes is on and the gesture was diagonal
// enough to also be a horizontal swipe.
gesture.swipedHorizontal;
// This will always be true for a downward swipe.
gesture.swipedVertical;
});

gesture.on('tap', (event) => {
// The gesture was a tap. Keep in mind, it may have also been a long press.
});

gesture.on('doubletap', (event) => {
// The gesture was a double tap. The 'tap' event will also have been fired on
// the first tap.
});

gesture.on('longpress', (event) => {
// The gesture is currently ongoing, and is now a long press.
});

gesture.on('pinch', (event) => {
// The gesture is an ongoing pinch.

// This is the current scale of the pinch. <1 means the user is zooming out.
// >1 means the user is zooming in.
gesture.scale;
});

gesture.on('pinchend', (event) => {
// The pinch gesture is completed.
});

gesture.on('rotate', (event) => {
// The gesture is an ongoing rotate.

// This is the current angle of the rotation, in degrees.
gesture.rotation;
});

gesture.on('rotateend', (event) => {
// The rotate gesture is completed.
});
`

$3

If you want to listen for both long press and tap, and distinguish between them, this is how to do it.

`js
let pressed = false;

// Note: don't use the 'tap' event to detect when the user has finished a long
// press, because it doesn't always fire.
gesture.on('tap', () => {
// If the user long pressed, don't run the tap handler. This event fires after
// the user lifts their finger.
if (pressed) {
return;
}
// ... Your tap handling code here.
});

gesture.on('longpress', () => {
// Indicate that this is a long press. This event fires before the user lifts
// their finger.
pressed = true;
// ... Your long press ongoing handling code here.
});

gesture.on('panend', () => {
// This is how you would detect when the user has finished a long press,
// because 'panend' will always fire, even if the user has moved their finger
// a little after 'longpress' has fired.
if (pressed) {
// ... Your long press finished handling code here.

// Make sure to reset pressed after the current event loop.
setTimeout(() => {
pressed = false;
}, 0);
}
});
`

$3

`js
// There are two ways to un-listen:
const callback = (event) => {};
const listener = gesture.on('tap', callback);
// First way.
listener.cancel();
// Second way.
gesture.off('tap', callback);
`

$3

`js
// If, for some reason, you want to programmatically fire all the listeners for
// some event:
gesture.fire('tap', eventObj);
`

$3

`js
// When you're done, you can remove event listeners with:
gesture.destroy();
``

Credits

A lot of the initial ideas and code came from:

https://gist.github.com/SleepWalker/da5636b1abcbaff48c4d

and

https://github.com/uxitten/xwiper