WIP Add touch events for all components

src/MultiSlider/MultiSliderHandle.js

@@ -2,6 +2,7 @@ import React from 'react';
 import PropTypes from 'prop-types';
 
 import { noop } from '../util/functions';
+import normalizeEvent from '../util/normalize-event';
 
 import './MultiSliderHandle.css';
 
@@ -12,6 +13,7 @@ class MultiSliderHandle extends React.PureComponent {
 	}
 
 	startInteraction(e) {
+		e = normalizeEvent(e);
 		this.props.onStart(e, this.props.property);
 	}
 
@@ -26,6 +28,7 @@ class MultiSliderHandle extends React.PureComponent {
 			<div
 				className="uix-multislider__handle"
 				onMouseDown={this.startInteraction}
+				onTouchStart={this.startInteraction}
 				style={styles}
 			/>
 		);

src/Pad/stories/index.stories.js

@@ -2,7 +2,7 @@ import React from 'react';
 
 import { storiesOf } from '@storybook/react';
 import { action } from '@storybook/addon-actions';
-import State from '../../Husk/Husk';
+import Husk from '../../Husk/Husk';
 
 import Pad from '../Pad';
 import PadGrid from '../PadGrid';

src/Position/Position.js

@@ -1,6 +1,7 @@
 import React from 'react';
 import PropTypes from 'prop-types';
 import { noop } from '../util/functions';
+import normalizeEvent, { isTouchEnabledDevice } from '../util/normalize-event';
 
 /*
 	Component: Position
@@ -24,14 +25,23 @@ class Position extends React.PureComponent {
 	componentDidMount() {
 		document.addEventListener('mousemove', this.onChange);
 		document.addEventListener('mouseup', this.onEnd);
+		if (isTouchEnabledDevice()) {
+			document.addEventListener('touchmove', this.onChange);
+			document.addEventListener('touchend', this.onEnd);
+		}
 	}
 
 	componentWillUnmount() {
 		document.removeEventListener('mousemove', this.onChange);
 		document.removeEventListener('mouseup', this.onEnd);
+		if (isTouchEnabledDevice()) {
+			document.removeEventListener('touchmove', this.onChange);
+			document.removeEventListener('touchend', this.onEnd);
+		}
 	}
 
 	onChange(e) {
+		e = normalizeEvent(e);
 		this.props.onChange(
 			{
 				x: e.clientX,
@@ -44,6 +54,7 @@ class Position extends React.PureComponent {
 	}
 
 	onEnd(e) {
+		e = normalizeEvent(e);
 		this.props.onEnd(
 			{
 				x: e.clientX,

src/Position/stories/index.stories.js

@@ -32,16 +32,17 @@ storiesOf('Position', module)
 				this.state = {
 					interacting: false
 				};
+				this.startInteraction = this.startInteraction.bind(this);
+			}
+
+			startInteraction(e) {
+				this.setState({ interacting: true });
+				e.preventDefault();
 			}
 
 			render() {
 				return (
-					<div
-						onMouseDown={e => {
-							this.setState({ interacting: true });
-							e.preventDefault();
-						}}
-					>
+					<div onMouseDown={this.startInteraction} onTouchStart={this.startInteraction}>
 						<p>
 							Hold down the mouse here and move it to read its coordinates:{' '}
 							{this.state.x}: {this.state.y}

src/Surface/Surface.js

@@ -5,6 +5,7 @@ import { scaleLinear } from 'd3-scale';
 
 import Position from '../Position/Position';
 import { noop } from '../util/functions';
+import normalizeEvent, { isTouchEnabledDevice } from '../util/normalize-event';
 
 import './Surface.css';
 
@@ -22,7 +23,6 @@ const initial_state = {
 	for the X and Y coordinates in percentages (interval [0..100]).
 
 */
-
 class Surface extends React.Component {
 	constructor(props) {
 		super(props);
@@ -42,6 +42,7 @@ class Surface extends React.Component {
 	}
 
 	start(e) {
+		e = normalizeEvent(e);
 		this.setState({
 			interacting: true
 		});
@@ -54,6 +55,7 @@ class Surface extends React.Component {
 	}
 
 	end(e) {
+		e = normalizeEvent(e);
 		this.setState({
 			interacting: false
 		});
@@ -75,6 +77,7 @@ class Surface extends React.Component {
 	}
 
 	insert(e) {
+		e = normalizeEvent(e);
 		this.props.onInsert(
 			this.scale({
 				x: e.clientX,
@@ -92,6 +95,8 @@ class Surface extends React.Component {
 		let events = {};
 		if (passive) {
 			events['onDoubleClick'] = this.insert;
+		} else if (isTouchEnabledDevice()) {
+			events['onTouchMove'] = this.start;
 		} else {
 			events['onMouseDownCapture'] = this.start;
 		}

src/util/normalize-event.js

@@ -0,0 +1,85 @@
+const proxiedValues = ['clientX', 'clientY', 'pageX', 'pageY', 'screenX', 'screenY'];
+
+const proxiedFunctions = ['preventDefault', 'stopPropagation', 'stopImmediatePropagation'];
+
+var EventProxy = {
+	apply: function(obj, thisArg, argumentList) {
+		return obj.apply(obj, argumentList);
+	},
+
+	get: function(obj, prop) {
+		if (obj.changedTouches && obj.changedTouches[0] && proxiedValues.indexOf(prop) > -1) {
+			return obj.changedTouches[0][prop];
+		}
+
+		if (
+			obj.detail &&
+			obj.detail.changedTouches &&
+			obj.detail.changedTouches[0] &&
+			proxiedValues.indexOf(prop) > -1
+		) {
+			return obj.detail.changedTouches[0][prop];
+		}
+
+		if (prop == 'original') {
+			if (obj.detail && obj.detail.original) {
+				return obj.detail.original;
+			}
+			return obj;
+		}
+
+		if (obj.type === 'touchend' && prop === 'target') {
+			let clientX, clientY;
+			if (obj.changedTouches && obj.changedTouches[0]) {
+				clientX = obj.changedTouches[0].clientX;
+				clientY = obj.changedTouches[0].clientY;
+			} else if (obj.detail && obj.detail.changedTouches && obj.detail.changedTouches[0]) {
+				clientX = obj.detail.changedTouches[0].clientX;
+				clientY = obj.detail.changedTouches[0].clientY;
+			}
+			return document.elementFromPoint(clientX, clientY);
+		}
+
+		if (proxiedFunctions.indexOf(prop) > -1) {
+			if (obj.detail && obj.detail.original && obj.detail.original[prop]) {
+				return obj.detail.original[prop].bind(obj);
+			}
+			return obj[prop].bind(obj);
+		}
+
+		return obj[prop];
+	}
+};
+
+let __isTouchEnabledDevice;
+function isTouchEnabledDevice() {
+	return __isTouchEnabledDevice !== undefined
+		? __isTouchEnabledDevice
+		: (__isTouchEnabledDevice = (function() {
+				// we rely on Proxy for events that come from touch-enabled devices,
+				// so if we don't have it we need to assume this is not such a device.
+				if (!window.Proxy) {
+					return false;
+				}
+				try {
+					new CustomEvent('longtap');
+				} catch (e) {
+					return false;
+				}
+				/*
+				 	As per https://developer.mozilla.org/en-US/docs/Web/API/Navigator/maxTouchPoints
+				 	a device should expose how many touch points are supported; unfortunately 
+				 	mobile Safari does not support it, so we have to also taste for ontouchstart for iPads.
+				 */
+				return (
+					window.ontouchstart !== undefined ||
+					navigator.maxTouchPoints ||
+					navigator.msMaxTouchPoints
+				);
+		  })());
+}
+
+const normalizeEvent = e => (isTouchEnabledDevice() ? new Proxy(e, EventProxy) : e);
+
+export default normalizeEvent;
+export { isTouchEnabledDevice };