Getting touchy – An introduction to touch and pointer events

Transcript

1. getting touchy AN INTRODUCTION TO TOUCH AND POINTER EVENTS Patrick H. Lauke / Frontend NE / 2 March 2017
2. about me... •  senior accessibility consultant at The Paciello Group •  previously developer relations at Opera •  co-editor Touch Events Level 2 •  WG chair and co-editor Pointer Events Level 2
3. github.com/patrickhlauke/getting-touchy-presentation "evergreen" expanded version of this presentation (and branches for specific conferences)
4. patrickhlauke.github.io/touch
6. Touch/pointer events test results
7. my JavaScript sucks... (but will hopefully convey the right concepts)
8. how can I make my website work on touch devices?
9. you don't need touch events browsers emulate regular mouse events
10. patrickhlauke.github.io/touch/tests/event-listener_mouse-only.html
11. patrickhlauke.github.io/touch/tests/event-listener_mouse-only.html
12. compatibility mouse events (mouseenter) > mouseover > mousemove* > mousedown > (focus) > mouseup > click * only a single sacrificial mousemove event fired
13. on first tap (mouseenter) > mouseover > mousemove > mousedown > (focus) > mouseup > click subsequent taps mousemove > mousedown > mouseup > click tapping away (mouseout) > (blur) focus / blur only on focusable elements; subtle differences between browsers Mobile/tablet touchscreen activation/tap event order
14. emulation works, but is limiting/problematic
15. 1.  delayed event dispatch 2.  mousemove doesn't track
16. 1.  delayed event dispatch 2.  mousemove doesn't track
17. patrickhlauke.github.io/touch/tests/event-listener_show-delay.html less of a problem in modern browsers, but for iOS < 9.3 or older Androids still relevant
18. patrickhlauke.github.io/touch/tests/event-listener_show-delay.html
19. 1.  delayed event dispatch 2.  mousemove doesn't track
20. patrickhlauke.github.io/touch/particle/2
21. patrickhlauke.github.io/touch/particle/2
22. we need to go deeper...
23. touch events introduced by Apple, adopted in Chrome/Firefox/Opera (and belatedly IE/Edge – more on that later) www.w3.org/TR/touch-events
24. caniuse.com: Can I use touch events?
25. touchstart touchmove touchend touchcancel
26. patrickhlauke.github.io/touch/tests/event-listener_all-no-timings.html Bug 128534 - 'mouseenter' mouse compat event not fired...
27. events fired on tap touchstart > [touchmove]+ > touchend > (mouseenter) > mouseover > mousemove > mousedown > (focus) > mouseup > click (mouse events only fired for single-finger tap)
28. on first tap touchstart > [touchmove]+ > touchend > (mouseenter) > mouseover > mousemove > mousedown > (focus) > mouseup > click subsequent taps touchstart > [touchmove]+ > touchend > mousemove > mousedown > mouseup > click tapping away mouseout > (mouseleave) > (blur)
29. •  too many touchmove events prevent mouse compatibility events after touchend (not considered a "clean" tap) •  too many touchmove events on activatable elements can lead to touchcancel (in old Chrome/Browser versions) •  not all browsers consistently send touchmove •  differences in focus / blur and some mouse compatibility events (e.g. mouseenter / mouseleave ) •  some events may only fire when tapping away to another focusable element (e.g. blur ) some browsers outright weird...
30. Browser/Android 4.3 mouseover > mousemove > touchstart > touchend > mousedown > mouseup > click Browser/Blackberry PlayBook 2.0 touchstart > mouseover > mousemove > mousedown > touchend > mouseup > click UC Browser 10.8/Android 6 mouseover > mousemove > touchstart > (touchmove)+ > touchend > mousedown > focus > mouseup > click
31. Touch/pointer events test results
32. shouldn't affect your code, unless you're expecting a very specific sequence...
33. <interlude > simple feature detection for touch events
34. / feature detection for touch events */ if ( 'ontouchstart' in window ) { /* some clever stuff here */ } /* older browsers have flaky support so more hacky tests needed...use Modernizr.touch or similar */
35. patrickhlauke.github.io/touch/tests/touch-feature-detect.html
36. /* conditional "touch OR mouse/keyboard" event binding */ if ('ontouchstart' in window) { // set up event listeners for touch ... } else { // set up event listeners for mouse/keyboard ... }
37. don't make it touch-exclusive
38. hybrid devices touch + mouse + keyboard
41. @patrick_h_lauke showing a naive "touch or mouse" issue on Flickr (which has since been fixed)
42. Bug 888304 - touch-events on Firefox-desktop should be disabled until we can support them properly
43. Issue 392584: TouchEvent API should be enabled consistently
44. Chrome now returns window.TouchEvent on non-touch devices patrickhlauke.github.io/touch/tests/touch-feature-detect.html
45. even on "mobile" we can have multiple inputs...
48. Android + mouse – like touch (mouse emulating touch) touchstart > touchend > mouseover > mousemove > mousedown > (focus) > mouseup > click
49. Blackberry PlayBook 2.0 + mouse – like desktop mouseover > mousedown > (mousemove)+ > mouseup > click
50. Blackberry Leap (BBOS 10.1) + mouse – like desktop mouseover > mousedown > (mousemove)+ > mouseup > click
51. Windows 10 Mobile/Microsoft Edge + mouse – like desktop mouse events (+ pointer events) + click
52. Windows 10 Mobile/Microsoft Edge + keyboard – like desktop focus > click
53. Android + keyboard – like desktop focus > click
54. iOS keyboard only works in same situations as on-screen keyboard (e.g. text inputs, URL entry)
55. VoiceOver enables full keyboard access on iOS
56. iOS + keyboard – similar to touch focus ¡ touchstart > touchend > (mouseenter) > mouseover > mousemove > mousedown > blur > mouseup > click
57. further scenarios? •  desktop with external touchscreen •  touchscreen laptop with non-touch second screen •  touchscreen laptop with trackpad/mouse •  ...and other permutations?
58. no way to detect these cases...
59. Modernizr.touch detects touch events not touch devices
60. Stu Cox: “ou can't detect a touchscreen
61. hacks.mozilla.org - Detecting touch [...]
62. /* feature detection for touch events */ if ('ontouchstart' in window) { /* browser supports touch events but user is not necessarily using touch (exclusively) */ /* it could be a mobile, tablet, desktop, fridge ... */ }
63. touch or mouse or keyboard
64. touch and mouse and keyboard
65. what about CSS4 Media Queries?
66. W3C Media Queries Level 4 (Editor's Draft)
67. /* MQ4 Interaction Media Features*/ pointer: none | coarse | fine hover: none | hover any-pointer: none | coarse | fine any-hover: none | hover hover: on-demand / any-hover: on-demand removed in recent drafts
68. dev.opera - Interaction Media Features and their potential (for incorrect assumptions)
69. patrickhlauke.github.io/touch/pointer-hover-any-pointer-any-hover primary input is unchanged (and Chrome/Android required a full restart)
70. /* Naive uses of Interaction Media Features */ @media (pointer: fine) { /* primary input has fine pointer precision... so make all buttons/controls small? */ } @media (hover: hover) { /* primary input has hover...so we can rely on it? */ } /* pointer and hover only check "primary" input, but what if there's a secondary input that lacks capabilities? */
71. /* Better uses of Interaction Media Features */ @media (any-pointer: coarse) { /* at least one input has coarse pointer precision... provide larger buttons/controls for touch */ } /* test for *any* "least capable" inputs (primary or not) */ Limitation: [mediaqueries-4] any-hover can't be used to detect mixed hover and non-hover capable pointers. Also, pointer / hover / any-pointer / any-hover don't cover non-pointer inputs (e.g. keyboards) – always assume non-hover-capable inputs @media (any-hover: none) { /* at least one input lacks hover capability... don't rely on it or avoid altogether */ }
72. detect which input the users is using right now...
73. GitHub: ten1seven / what-input
74. Demo: What Input?
75. if in doubt, offer a way to switch interfaces... or just always use a touch-optimised interface
76. <¢ interlude >
77. touch events vs limitations/problems
78. 1.  delayed event dispatch 2.  mousemove doesn't track
79. 1.  delayed event dispatch 2.  mousemove doesn't track
80. patrickhlauke.github.io/touch/tests/event-listener_show-delay.html less of a problem in modern browsers, but for iOS < 9.3 or older Androids still relevant
81. why the delay? double-tap to zoom (mostly anyway)
82. when does the delay happen?
83. patrickhlauke.github.io/touch/tests/event-listener.html
84. touch / mouse events delay touchstart > [touchmove]+ > touchend > [300ms delay] (mouseenter) > mouseover > mousemove > mousedown > (focus) > mouseup > click
85. how can we make it feel responsive like a native app?
86. react to events fired before the 300ms delay...
87. touchstart for an immediate control (e.g. fire/jump button on a game)
88. touchend for a control that fires after finger lifted (but this can result in events firing after zoom/scroll)
89. don't make it touch-exclusive
90. /* DON'T DO THIS: conditional "touch OR mouse/keyboard" event binding */ if ('ontouchstart' in window) { // set up event listeners for touch foo.addEventListener('touchend', ...); ... } else { // set up event listeners for mouse/keyboard foo.addEventListener('click', ...); ... }
91. patrickhlauke.github.io/touch/tests/event-listener_naive-touch-or-mouse.html
92. /* DO THIS: doubled-up "touch AND mouse/keyboard" event binding */ // set up event listeners for touch foo.addEventListener('touchend', ...); // set up event listeners for mouse/keyboard foo.addEventListener('click', ...); /* but this would fire our function twice for touch? */ patrickhlauke.github.io/touch/tests/event-listener_naive-event-doubling.html
93. /* DO THIS: doubled-up "touch AND mouse/keyboard" event binding */ // set up event listeners for touch foo.addEventListener('touchend', function(e) { // prevent compatibility mouse events and click e.preventDefault(); ... }); // set up event listeners for mouse/keyboard foo.addEventListener('click', ...); patrickhlauke.github.io/touch/tests/event-listener_naive-event-doubling-fixed.html
94. preventDefault() kills scrolling, pinch/zoom, etc
95. apply preventDefault() carefully (just on buttons/links, not entire page)
96. github.com/ftlabs/fastclick
97. patrickhlauke.github.io/touch/fastclick “ouTube: iOS/Safari 300ms click delay: vanilla Bootstrap and using fastclick.js
98. patrickhlauke.github.io/touch/fastclick/fastclick.html “ouTube: iOS/Safari 300ms click delay: vanilla Bootstrap and using fastclick.js
99. browsers working to remove double-tap to zoom delay
100. non-scalable/zoomable viewport and "double-tap to zoom"
101. <meta name="viewport" content="user-scalable=no"> patrickhlauke.github.io/touch/tests/event-listener_user-scalable-no.html
102. Changeset 191072 - Web pages with unscalable viewports shouldn't have a single tap delay (from iOS 9.3 onwards)
103. what about accessibility?
104. Chrome: Settings > Accessibility > Force enable zoom
105. Opera: Settings > Force enable zoom
106. Firefox: Settings > Accessibility > Always enable zoom
107. Samsung Internet: Internet settings > Manual zoom
108. "Force enable zoom" reintroduces delay – a fair compromise? patrickhlauke.github.io/touch/tests/event-listener_user-scalable-no.html
109. @thomasfuchs - Safari/iOS10beta3 ignores unscalable viewports (no official Apple documentation about the change...but the 300ms delay is back)
110. Windows 10 build 15007 on Mobile ignores unscalable viewports
111. "mobile optimised" viewport and "double-tap to zoom"
112. Chrome 32+ / Android: content="width=device-width" suppresses double-tap-to-zoom, still allows pinch zoom Google Developers: 300ms tap delay, gone away
113. Bug 941995 - Remove 300ms [...] on "responsive" pages [RESOLVED FIXED]
114. WebKit blog: More Responsive Tapping on iOS
115. patrickhlauke.github.io/touch/tests/results/#suppressing-300ms-delay
116. suppressing 300ms delay if your code does rely on handling click / mouse events: •  "mobile optimised" <meta name="viewport" content="width=device-width"> •  add touch-action:manipulation in CSS (part of Pointer Events) •  use helper library like fastclick.js for older browsers •  make your viewport non-scalable...
117. 1.  delayed event dispatch 2.  mousemove doesn't track
118. patrickhlauke.github.io/touch/particle/2
119. patrickhlauke.github.io/touch/particle/2
120. events fired on tap touchstart > [touchmove]+ > touchend > (mouseenter) > mouseover > mousemove* > mousedown > (focus) > mouseup > click * mouse event emulation fires only a single mousemove too many touchmove events prevent mouse compatibility events after touchend
121. doubling up handling of mousemove and touchmove
122. £ar posX, posY; function positionHandler(e) { posX = e.clientX ; posY = e.clientY ; } canvas.addEventListener(' mousemove ', positionHandler, false);
123. ¤ar posX, posY; function positionHandler(e) { posX = e.clientX ; posY = e.clientY ; } canvas.addEventListener(' mousemove ', positionHandler, false); canvas.addEventListener(' touchmove ', positionHandler, false); /* but this won't work for touch... */
124. interface MouseEvent : UIEvent { readonly attribute long screenX ; readonly attribute long screenY ; readonly attribute long clientX ; readonly attribute long clientY ; readonly attribute boolean ctrlKey; readonly attribute boolean shiftKey; readonly attribute boolean altKey; readonly attribute boolean metaKey; readonly attribute unsigned short button; readonly attribute EventTarget relatedTarget; // [DOM4] UI Events readonly attribute unsigned short buttons; }; www.w3.org/TR/DOM-Level-2-Events/events.html#Events-MouseEvent www.w3.org/TR/uievents/#events-mouseevents
125. partial interface MouseEvent { readonly attribute double screenX; readonly attribute double screenY; readonly attribute double pageX ; readonly attribute double pageY ; readonly attribute double clientX; readonly attribute double clientY; readonly attribute double x ; readonly attribute double y ; readonly attribute double offsetX ; readonly attribute double offsetY ; }; www.w3.org/TR/cssom-view/#extensions-to-the-mouseevent- interface
126. interface TouchEvent : UIEvent { readonly attribute TouchList touches ; readonly attribute TouchList targetTouches ; readonly attribute TouchList changedTouches ; readonly attribute boolean altKey; readonly attribute boolean metaKey; readonly attribute boolean ctrlKey; readonly attribute boolean shiftKey; }; www.w3.org/TR/touch-events/#touchevent-interface
127. interface Touch { readonly attribute long identifier; readonly attribute EventTarget target; readonly attribute long screenX ; readonly attribute long screenY ; readonly attribute long clientX ; readonly attribute long clientY ; readonly attribute long pageX ; readonly attribute long pageY ; }; www.w3.org/TR/touch-events/#touch-interface
128. TouchList differences touches all touch points on screen targetTouches all touch points that started on the element changedTouches touch points that caused the event to fire
129. patrickhlauke.github.io/touch/touchlist-objects
130. ¥ar posX, posY; function positionHandler(e) { if ((e.clientX)&&(e.clientY)) { posX = e.clientX; posY = e.clientY; } else if (e.targetTouches) { posX = e.targetTouches[0].clientX; posY = e.targetTouches[0].clientY; e.preventDefault() ; } } canvas.addEventListener('mousemove', positionHandler, false ); canvas.addEventListener('touchmove', positionHandler, false );
131. patrickhlauke.github.io/touch/particle/3
132. patrickhlauke.github.io/touch/paranoid_0.5 www.splintered.co.uk/experiments/archives/paranoid_0.5
133. patrickhlauke.github.io/touch/picture-slider
134. tracking finger movement over time ... swipe gestures
135. patrickhlauke.github.io/touch/swipe
136. /* Swipe detection from basic principles */ Δt = end.time - start.time; Δx = end.x - start.x; Δy = end.y - start.y; if (( Δt > timeThreshold ) || ( (Δx + Δy) < distanceThreshold )) { /* too slow or movement too small */ } else { /* it's a swipe! - use ¦x and ¦y to determine direction - pythagoras √( ¦x² + ¦y² ) for distance - distance/¦t to determine speed */ }
137. don't forget mouse/keyboard!
138. touchmove fires...a lot!
139. do absolute minimum on each touchmove (usually: store coordinates)
140. do heavy lifting (drawing etc.) separately, avoid queueing (e.g. using setTimeout and/or requestAnimationFrame )
141. debounce / throttle events
142. GitHub: m-gagne / limit.js
143. patrickhlauke.github.io/touch/touch-limit
144. why stop at a single point? multitouch support
145. interface TouchEvent : UIEvent { readonly attribute TouchList touches ; readonly attribute TouchList targetTouches ; readonly attribute TouchList changedTouches ; readonly attribute boolean altKey; readonly attribute boolean metaKey; readonly attribute boolean ctrlKey; readonly attribute boolean shiftKey; }; www.w3.org/TR/touch-events/#touchevent-interface
146. /* iterate over relevant TouchList */ for (i=0; i< e.targetTouches .length; i++) { ... posX = e.targetTouches[i].clientX ; posY = e.targetTouches[i].clientY ; ... }
147. patrickhlauke.github.io/touch/tracker/multi-touch-tracker.html
148. iOS/iPad preventDefault() can't override 4-finger gestures
149. iOS7+ Safari/WebView preventDefault() can't override edge swipes
150. multitouch gestures
151. /* iOS/Safari/WebView has gesture events for size/rotation, not part of the W3C Touch Events spec. */ /* gesturestart / gesturechange / gestureend */ foo.addEventListener('gesturechange', function(e) { /* e.scale e.rotation */ /* values can be plugged directly into CSS transforms etc */ }); /* not supported in Chrome/Firefox/Opera */ iOS Developer Library - Safari Web Content Guide - Handling gesture events
152. /* Pinch/rotation detection from basic principles */ Δx = x2 - x1; Δy = y2 - y1; /* pythagoras √( §x² + §y² ) to calculate distance */ Δd = Math.sqrt( (Δx * Δx) + (Δy * Δy) ); /* trigonometry to calculate angle */ α = Math.atan2( Δy, Δx ); Mozilla Developer Network: Math.atan2()
153. patrickhlauke.github.io/touch/picture-organiser
154. Touch Events specification grey areas...
155. do touch events fire during scroll/zoom?
156. not defined in spec (yet), but de facto yes in most modern browsers patrickhlauke.github.io/touch/gesture-touch
157. Touch Events extensions...
158. W3C Touch Events Extensions WG Note
159. /* Extension to touch objects */ partial interface Touch { readonly attribute float radiusX; readonly attribute float radiusY; readonly attribute float rotationAngle; readonly attribute float force; };
160. /* Touch Events – contact geometry */ partial interface Touch { readonly attribute float radiusX ; readonly attribute float radiusY ; readonly attribute float rotationAngle ; readonly attribute float force; };
161. patrickhlauke.github.io/touch/tracker/tracker-radius-rotationangle.html “ouTube: Touch Events: radiusX, radius“ and rotationAngle
162. /* Touch Events – force */ partial interface Touch { readonly attribute float radiusX; readonly attribute float radiusY; readonly attribute float rotationAngle; readonly attribute float force ; }; force : value in range 0 – 1 . if no hardware support 0 (some devices, e.g. Nexus 10, "fake" force based on radiusX / radiusY )
163. patrickhlauke.github.io/touch/tracker/tracker-force-pressure.html iPhone 6s with 3D Touch supports force ... (Safari and WKWebView, e.g. Chrome/iOS, but not UIWebView, e.g. Firefox/iOS)
164. W3C Touch Events Level 2 (Editor's Draft) (merges errata, touch events extensions, fractional touch coordinates)
165. Pointer Events
166. up to IE9 (Win7 / WinPhone7.5) only mouse events
167. in IE10 Microsoft introduced Pointer Events
168. unifies mouse, touch and pen input into a single event model
169. ...and some new inputs (though currently mapped to mouse) Building Xbox One Apps using HTML and JavaScript “ouTube: Xbox One Edge Browser sends Pointer Events
170. not just some not invented here technology
171. submitted by Microsoft as W3C Candidate REC 09 May 2013
172. Pointer Events - W3C REC 24 February 2015
173. work now continues to enhance/expand Pointer Events... W3C Pointer Events Level 2 (Editor's Draft)
174. caniuse.com: Can I use pointer events?
175. Bug 822898 - Implement pointer events
176. about:config ¨ dom.w3c_pointer_events.enabled
177. ...what about Apple?
178. Microsoft submitted a proof of concept WebKit patch html5labs.interoperabilitybridges.com/prototypes/...
179. Bug 105463 - Implement pointer events RESOLVED WONTFIX
180. Maciej Stachowiak - [webkit-dev] pointer events specification - first editors draft
181. @patrick_h_lauke paraphrasing Apple's stance on Pointer Events...
183. Apple Pencil currently indistinguishable from touch in browser / JavaScript (no tilt information, fires touch events)
184. the anatomy of Pointer Events (sequence, event object, ...)
185. patrickhlauke.github.io/touch/tests/event-listener_all-no-timings.html
186. events fired on tap (Edge) mousemove* > pointerover > mouseover > pointerenter > mouseenter > pointerdown > mousedown > focus gotpointercapture > pointermove > mousemove > pointerup > mouseup > lostpointercapture > click > pointerout > mouseout > pointerleave > mouseleave mouse events fired inline with pointer events (for a primary pointer, e.g. first finger on screen)
187. IE10/IE11 quirks •  vendor-prefixed in IE10 ( MSPointerDown ..., navigator.msMaxTouchPoints , -ms-touch-action ) •  unprefixed in IE11 (but prefixed versions mapped for compatibility) •  event order (when click is fired) incorrect in IE10/IE11 see W3C Pointer Events WG mailing list - Jacob Rossi (Microsoft)
188. Chrome, Edge (on mobile), IE11 (Windows Phone 8.1update1) support both Touch Events and Pointer Events w3c.github.io/pointerevents/#mapping-for-devices-that-do-not-support-hover
189. patrickhlauke.github.io/touch/tests/event-listener_all-no-timings.html
190. about:flags in Microsoft Edge to turn on touch events on desktop (e.g. touch-enabled laptops) – off by default for site compatibility
191. ... when touch events also supported (Edge) pointerover > pointerenter > pointerdown > touchstart > pointerup > touchend > mouseover > mouseenter > mousemove > mousedown > focus > mouseup > click > pointerout > pointerleave Specific order of events is not defined in the spec in this case – will vary between browsers... only problem if handling both pointer events and mouse events (which is nonsensical)
192. /* Pointer Events extend Mouse Events vs Touch Events and their new objects / TouchLists / Touches */ interface PointerEvent : MouseEvent { readonly attribute long pointerId; readonly attribute long width; readonly attribute long height; readonly attribute float pressure; readonly attribute float tangentialPressure; /* Level 2 */ readonly attribute long tiltX; readonly attribute long tiltY; readonly attribute long twist; /* Level 2 */ readonly attribute DOMString pointerType; readonly attribute boolean isPrimary; }
193. handling mouse input is exactly the same as traditional mouse events (only change pointer* instead of mouse* event names)
194. handling touch or stylus is also exactly the same as traditional mouse events (mouse code can be adapted to touch/stylus quickly)
195. simple feature detection for pointer events
196. /* detecting pointer events support */ if ( window.PointerEvent ) { /* some clever stuff here but this covers touch, stylus, mouse, etc */ } /* still listen to click for keyboard! */
197. "don't forget about keyboard users" note in Pointer Events spec
198. /* detect maximum number of touch points */ if ( navigator.maxTouchPoints > 0 ) { /* device with a touchscreen */ } if ( navigator.maxTouchPoints > 1 ) { /* multitouch-capable device */ } "you can detect a touchscreen" ...but user may still use other input mechanisms
199. patrickhlauke.github.io/touch/tests/pointer-multitouch-detect.html
200. do pointer events fire during scroll/zoom?
201. w3c.github.io/pointerevents/#the-pointercancel-event
202. once a browser handles scrolling, it sends pointercancel patrickhlauke.github.io/touch/gesture-touch/pointerevents.html
203. pointer events vs limitations/problems of mouse event emulation
204. 1.  delayed event dispatch 2.  mousemove doesn't track
205. 1.  delayed event dispatch 2.  mousemove doesn't track
206. patrickhlauke.github.io/touch/tests/event-listener.html (IE11/WinPhone 8.1 Update no optimization for width=device-width )
207. patrickhlauke.github.io/touch/tests/event-listener.html (IE/Win8 has double-tap to zoom, so problem on desktop too)
208. patrickhlauke.github.io/touch/tests/event-listener.html (Microsoft Edge/Win10 has double-tap to zoom, so problem on desktop too)
209. pointer / mouse events and delay ©©© [300ms delay] click ... 300ms delay just before click event
210. how can we make it feel responsive like a native app?
211. we could try a similar approach to touch events...
212. •  double-up pointerup and click listeners? •  prevent code firing twice with preventDefault ? won't work: preventDefault() stops mouse compatibility events, but click is not considered mouse compatibility event
213. a more declarative approach with touch-action
214. CSS property what action should the browser handle? touch-action: auto | none | [ pan-x || pan-y ] | manipulation www.w3.org/TR/pointerevents/#the-touch-action-css-property only determines default touch action, does not stop compatibility mouse events nor click
215. Pointer Events Level 2 expanded set of values (useful for pull-to-refresh, carousels, etc) touch-action: auto | none | [ [ pan-x | pan-left | pan-right ] || [ pan-y | pan-up | pan-down ] ] | manipulation w3c.github.io/pointerevents/#the-touch-action-css-property
216. compat.spec.whatwg.org add extra value pinch-zoom
217. patrickhlauke.github.io/touch/touch-action-scrolling
218. touch-action:none (suppress all default browser behaviour)
219. patrickhlauke.github.io/touch/tests/event-listener_touch[...]
220. touch-action:none kills scrolling, long-press, pinch/zoom
221. touch-action:manipulation (suppress double-tap-to-zoom)
222. patrickhlauke.github.io/touch/tests/event-listener_touch[...]
223. caniuse.com: Can I use touch-action?
224. browsers working to remove double-tap to zoom delay (when page not zoomable)
225. <meta name="viewport" content="user-scalable=no"> patrickhlauke.github.io/touch/tests/event-listener_user-scalable-no.html
227. "Allow zooming on all web content" reintroduces delay patrickhlauke.github.io/touch/tests/event-listener_user-scalable-no.html
228. "Allow zooming..." option currently missing in Win 10 Mobile
229. Windows 10 build 15007 on Mobile ignores unscalable viewports no delay until user zooms for first time...
230. width=device-width still has delay in IE11/WinPhone 8.1 Update patrickhlauke.github.io/touch/tests/event-listener_width-device-width.html
231. Microsoft Edge removes delay for width=device-width patrickhlauke.github.io/touch/tests/event-listener_width-device-width.html
232. patrickhlauke.github.io/touch/tests/results/#suppressing-300ms-delay
233. 1.  delayed event dispatch 2.  mousemove doesn't track
234. just listen to pointermove...
235. no need for separate mouse or touch event listeners
236. /* touch events: separate handling */ foo.addEventListener('touchmove', ... , false); foo.addEventListener('mousemove', ... , false); /* pointer events: single listener for mouse, stylus, touch */ foo.addEventListener(' pointermove ', ... , false);
237. no need for separate mouse or touch code to get x / y coords
238. /* Reminder: Touch Events need separate code for x / y coords */ function positionHandler(e) { if ((e.clientX)&&(e.clientY)) { posX = e.clientX; posY = e.clientY; } else if (e.targetTouches) { posX = e.targetTouches[0].clientX; posY = e.targetTouches[0].clientY; ... } } canvas.addEventListener('mousemove', positionHandler, false ); canvas.addEventListener('touchmove', positionHandler, false );
239. /* Pointer Events extend Mouse Events */ foo.addEventListener(' pointermove ', function(e) { ... posX = e.clientX ; posY = e.clientY ; ... }, false); www.w3.org/TR/pointerevents/#pointerevent-interface
240. 3D Rotator by Creative Punch coded to only use mouse events
241. 3D Rotator modified to use Pointer Events minimal code changes, as Pointer Events extend mouse events
242. but you can distinguish mouse or touch or stylus
243. foo.addEventListener('pointermove', function(e) { ... switch( e.pointerType ) { case ' mouse ': ... break; case ' pen ': ... break; case ' touch ': ... break; default : /* future-proof */ } ... } , false);
244. what about multitouch?
245. /* PointerEvents don't have the handy TouchList objects, so we have to replicate something similar... */ ar points = []; switch (e.type) { case ' pointerdown ': /* add to the array */ break; case ' pointermove ': /* update the relevant array entry's x and y */ break; case ' pointerup ': case ' pointercancel ': /* remove the relevant array entry */ break; }
246. patrickhlauke.github.io/touch/tracker/multi-touch-tracker-pointer-hud.html (note multiple isPrimary pointers, per pointer type)
247. /* like iOS/Safari, IE/Win has higher-level gestures , but these are not part of the W3C Pointer Events spec. Replicate these from basic principles again... */ MSDN IE10 Developer Guide: Gesture object and events
248. extended capabilities (if supported by hardware)
249. /* Pointer Events - pressure */ interface PointerEvent : MouseEvent { readonly attribute long pointerId; readonly attribute long width; readonly attribute long height; readonly attribute float pressure ; readonly attribute float tangentialPressure; readonly attribute long tiltX; readonly attribute long tiltY; readonly attribute long twist; readonly attribute DOMString pointerType; readonly attribute boolean isPrimary; } pressure : value in range 0 – 1 . if no hardware support, 0.5 in active button state, 0 otherwise
250. patrickhlauke.github.io/touch/tracker/... “ouTube: Touch tracker with Surface 3 pen
251. hovering stylus •  hardware-dependant •   pointermove fires •   pressure == 0 (non-active button state) •  track pointerdown / pointerup to be safe
252. /* Pointer Events - contact geometry */ interface PointerEvent : MouseEvent { readonly attribute long pointerId; readonly attribute long width ; readonly attribute long height ; readonly attribute float pressure; readonly attribute float tangentialPressure; readonly attribute long tiltX; readonly attribute long tiltY; readonly attribute long twist; readonly attribute DOMString pointerType; readonly attribute boolean isPrimary; } if hardware can't detect contact geometry, either 0 or "best guess" (e.g. for mouse/stylus, return width / height of 1 )
253. patrickhlauke.github.io/touch/tracker/tracker-width-height.html “ouTube: Pointer Events width and height ...
254. /* Pointer Events - tilt */ interface PointerEvent : MouseEvent { readonly attribute long pointerId; readonly attribute long width; readonly attribute long height; readonly attribute float pressure; readonly attribute float tangentialPressure; readonly attribute long tiltX ; readonly attribute long tiltY ; readonly attribute long twist; readonly attribute DOMString pointerType; readonly attribute boolean isPrimary; } tiltX / tiltY : value in degrees -90 – 90 . returns 0 if hardware does not support tilt
255. patrickhlauke.github.io/touch/pen-tracker “ouTube: ...pen with tilt, pressure and hover support
256. patrickhlauke.github.io/touch/pen-tracker “ouTube: Chrome on Samsung Galaxy Note 4 - Pointer Events and stylus
257. pointermove fires if any property changes, not just x/y position ( width , height , tiltX , tiltY , pressure )
258. pointer events as the future?
259. transitional event handling (until all browsers support pointer events)
260. /* cover all cases (hat-tip Stu Cox) */ if (window.PointerEvent) { /* bind to Pointer Events: pointerdown, pointerup, etc */ } else { /* bind to mouse events: mousedown, mouseup, etc */ if ('ontouchstart' in window) { /* bind to Touch Events: touchstart, touchend, etc */ } } /* bind to keyboard / click */
261. polyfills for pointer events (code for tomorrow, today)
262. GitHub - jQuery Pointer Events Polyfill (PEP)
263.  adding jQuery PEP * <script src="https:code.jquery.compep0.4.1pep.js"><script> * need to use custom touch-action attribute, not CSS (yet) * <button touch-action="none" >...<div>
264. patrickhlauke.github.io/touch/pep-draw
265. patrickhlauke.github.io/touch/pep/listener/event-listener.html
266. debugging/testing
267. nothing beats having real devices...
268. Chrome DevTools / Device Mode & Mobile Emulation correctly emulates touch and pointer events
269. Firefox Developer Tools > Responsive Design Mode correctly emulates touch events
270. no touch emulation, nor touch events + pointer events (like on real Windows 10 Mobile) emulation, in Edge/F12 Tools
271. no touch emulation in Safari "Responsive Design Mode"
272. youtube.com/watch?v=A”KpByV5764
273. get in touch @patrick_h_lauke github.com/patrickhlauke/touch patrickhlauke.github.io/getting-touchy-presentation slideshare.net/redux paciellogroup.com splintered.co.uk