Files
code-server/lib/vscode/src/vs/base/browser/touch.ts

364 lines
10 KiB
TypeScript

/*---------------------------------------------------------------------------------------------
* Copyright (c) Microsoft Corporation. All rights reserved.
* Licensed under the MIT License. See License.txt in the project root for license information.
*--------------------------------------------------------------------------------------------*/
import * as arrays from 'vs/base/common/arrays';
import { IDisposable, Disposable } from 'vs/base/common/lifecycle';
import * as DomUtils from 'vs/base/browser/dom';
import { memoize } from 'vs/base/common/decorators';
export namespace EventType {
export const Tap = '-monaco-gesturetap';
export const Change = '-monaco-gesturechange';
export const Start = '-monaco-gesturestart';
export const End = '-monaco-gesturesend';
export const Contextmenu = '-monaco-gesturecontextmenu';
}
interface TouchData {
id: number;
initialTarget: EventTarget;
initialTimeStamp: number;
initialPageX: number;
initialPageY: number;
rollingTimestamps: number[];
rollingPageX: number[];
rollingPageY: number[];
}
export interface GestureEvent extends MouseEvent {
initialTarget: EventTarget | undefined;
translationX: number;
translationY: number;
pageX: number;
pageY: number;
tapCount: number;
}
interface Touch {
identifier: number;
screenX: number;
screenY: number;
clientX: number;
clientY: number;
pageX: number;
pageY: number;
radiusX: number;
radiusY: number;
rotationAngle: number;
force: number;
target: Element;
}
interface TouchList {
[i: number]: Touch;
length: number;
item(index: number): Touch;
identifiedTouch(id: number): Touch;
}
interface TouchEvent extends Event {
touches: TouchList;
targetTouches: TouchList;
changedTouches: TouchList;
}
export class Gesture extends Disposable {
private static readonly SCROLL_FRICTION = -0.005;
private static INSTANCE: Gesture;
private static readonly HOLD_DELAY = 700;
private dispatched = false;
private targets: HTMLElement[];
private ignoreTargets: HTMLElement[];
private handle: IDisposable | null;
private activeTouches: { [id: number]: TouchData; };
private _lastSetTapCountTime: number;
private static readonly CLEAR_TAP_COUNT_TIME = 400; // ms
private constructor() {
super();
this.activeTouches = {};
this.handle = null;
this.targets = [];
this.ignoreTargets = [];
this._lastSetTapCountTime = 0;
this._register(DomUtils.addDisposableListener(document, 'touchstart', (e: TouchEvent) => this.onTouchStart(e), { passive: false }));
this._register(DomUtils.addDisposableListener(document, 'touchend', (e: TouchEvent) => this.onTouchEnd(e)));
this._register(DomUtils.addDisposableListener(document, 'touchmove', (e: TouchEvent) => this.onTouchMove(e), { passive: false }));
}
public static addTarget(element: HTMLElement): IDisposable {
if (!Gesture.isTouchDevice()) {
return Disposable.None;
}
if (!Gesture.INSTANCE) {
Gesture.INSTANCE = new Gesture();
}
Gesture.INSTANCE.targets.push(element);
return {
dispose: () => {
Gesture.INSTANCE.targets = Gesture.INSTANCE.targets.filter(t => t !== element);
}
};
}
public static ignoreTarget(element: HTMLElement): IDisposable {
if (!Gesture.isTouchDevice()) {
return Disposable.None;
}
if (!Gesture.INSTANCE) {
Gesture.INSTANCE = new Gesture();
}
Gesture.INSTANCE.ignoreTargets.push(element);
return {
dispose: () => {
Gesture.INSTANCE.ignoreTargets = Gesture.INSTANCE.ignoreTargets.filter(t => t !== element);
}
};
}
@memoize
private static isTouchDevice(): boolean {
// `'ontouchstart' in window` always evaluates to true with typescript's modern typings. This causes `window` to be
// `never` later in `window.navigator`. That's why we need the explicit `window as Window` cast
return 'ontouchstart' in window || navigator.maxTouchPoints > 0 || (window as Window).navigator.msMaxTouchPoints > 0;
}
public dispose(): void {
if (this.handle) {
this.handle.dispose();
this.handle = null;
}
super.dispose();
}
private onTouchStart(e: TouchEvent): void {
let timestamp = Date.now(); // use Date.now() because on FF e.timeStamp is not epoch based.
if (this.handle) {
this.handle.dispose();
this.handle = null;
}
for (let i = 0, len = e.targetTouches.length; i < len; i++) {
let touch = e.targetTouches.item(i);
this.activeTouches[touch.identifier] = {
id: touch.identifier,
initialTarget: touch.target,
initialTimeStamp: timestamp,
initialPageX: touch.pageX,
initialPageY: touch.pageY,
rollingTimestamps: [timestamp],
rollingPageX: [touch.pageX],
rollingPageY: [touch.pageY]
};
let evt = this.newGestureEvent(EventType.Start, touch.target);
evt.pageX = touch.pageX;
evt.pageY = touch.pageY;
this.dispatchEvent(evt);
}
if (this.dispatched) {
e.preventDefault();
e.stopPropagation();
this.dispatched = false;
}
}
private onTouchEnd(e: TouchEvent): void {
let timestamp = Date.now(); // use Date.now() because on FF e.timeStamp is not epoch based.
let activeTouchCount = Object.keys(this.activeTouches).length;
for (let i = 0, len = e.changedTouches.length; i < len; i++) {
let touch = e.changedTouches.item(i);
if (!this.activeTouches.hasOwnProperty(String(touch.identifier))) {
console.warn('move of an UNKNOWN touch', touch);
continue;
}
let data = this.activeTouches[touch.identifier],
holdTime = Date.now() - data.initialTimeStamp;
if (holdTime < Gesture.HOLD_DELAY
&& Math.abs(data.initialPageX - arrays.tail(data.rollingPageX)) < 30
&& Math.abs(data.initialPageY - arrays.tail(data.rollingPageY)) < 30) {
let evt = this.newGestureEvent(EventType.Tap, data.initialTarget);
evt.pageX = arrays.tail(data.rollingPageX);
evt.pageY = arrays.tail(data.rollingPageY);
this.dispatchEvent(evt);
} else if (holdTime >= Gesture.HOLD_DELAY
&& Math.abs(data.initialPageX - arrays.tail(data.rollingPageX)) < 30
&& Math.abs(data.initialPageY - arrays.tail(data.rollingPageY)) < 30) {
let evt = this.newGestureEvent(EventType.Contextmenu, data.initialTarget);
evt.pageX = arrays.tail(data.rollingPageX);
evt.pageY = arrays.tail(data.rollingPageY);
this.dispatchEvent(evt);
} else if (activeTouchCount === 1) {
let finalX = arrays.tail(data.rollingPageX);
let finalY = arrays.tail(data.rollingPageY);
let deltaT = arrays.tail(data.rollingTimestamps) - data.rollingTimestamps[0];
let deltaX = finalX - data.rollingPageX[0];
let deltaY = finalY - data.rollingPageY[0];
// We need to get all the dispatch targets on the start of the inertia event
const dispatchTo = this.targets.filter(t => data.initialTarget instanceof Node && t.contains(data.initialTarget));
this.inertia(dispatchTo, timestamp, // time now
Math.abs(deltaX) / deltaT, // speed
deltaX > 0 ? 1 : -1, // x direction
finalX, // x now
Math.abs(deltaY) / deltaT, // y speed
deltaY > 0 ? 1 : -1, // y direction
finalY // y now
);
}
this.dispatchEvent(this.newGestureEvent(EventType.End, data.initialTarget));
// forget about this touch
delete this.activeTouches[touch.identifier];
}
if (this.dispatched) {
e.preventDefault();
e.stopPropagation();
this.dispatched = false;
}
}
private newGestureEvent(type: string, initialTarget?: EventTarget): GestureEvent {
let event = document.createEvent('CustomEvent') as unknown as GestureEvent;
event.initEvent(type, false, true);
event.initialTarget = initialTarget;
event.tapCount = 0;
return event;
}
private dispatchEvent(event: GestureEvent): void {
if (event.type === EventType.Tap) {
const currentTime = (new Date()).getTime();
let setTapCount = 0;
if (currentTime - this._lastSetTapCountTime > Gesture.CLEAR_TAP_COUNT_TIME) {
setTapCount = 1;
} else {
setTapCount = 2;
}
this._lastSetTapCountTime = currentTime;
event.tapCount = setTapCount;
} else if (event.type === EventType.Change || event.type === EventType.Contextmenu) {
// tap is canceled by scrolling or context menu
this._lastSetTapCountTime = 0;
}
for (let i = 0; i < this.ignoreTargets.length; i++) {
if (event.initialTarget instanceof Node && this.ignoreTargets[i].contains(event.initialTarget)) {
return;
}
}
this.targets.forEach(target => {
if (event.initialTarget instanceof Node && target.contains(event.initialTarget)) {
target.dispatchEvent(event);
this.dispatched = true;
}
});
}
private inertia(dispatchTo: EventTarget[], t1: number, vX: number, dirX: number, x: number, vY: number, dirY: number, y: number): void {
this.handle = DomUtils.scheduleAtNextAnimationFrame(() => {
let now = Date.now();
// velocity: old speed + accel_over_time
let deltaT = now - t1,
delta_pos_x = 0, delta_pos_y = 0,
stopped = true;
vX += Gesture.SCROLL_FRICTION * deltaT;
vY += Gesture.SCROLL_FRICTION * deltaT;
if (vX > 0) {
stopped = false;
delta_pos_x = dirX * vX * deltaT;
}
if (vY > 0) {
stopped = false;
delta_pos_y = dirY * vY * deltaT;
}
// dispatch translation event
let evt = this.newGestureEvent(EventType.Change);
evt.translationX = delta_pos_x;
evt.translationY = delta_pos_y;
dispatchTo.forEach(d => d.dispatchEvent(evt));
if (!stopped) {
this.inertia(dispatchTo, now, vX, dirX, x + delta_pos_x, vY, dirY, y + delta_pos_y);
}
});
}
private onTouchMove(e: TouchEvent): void {
let timestamp = Date.now(); // use Date.now() because on FF e.timeStamp is not epoch based.
for (let i = 0, len = e.changedTouches.length; i < len; i++) {
let touch = e.changedTouches.item(i);
if (!this.activeTouches.hasOwnProperty(String(touch.identifier))) {
console.warn('end of an UNKNOWN touch', touch);
continue;
}
let data = this.activeTouches[touch.identifier];
let evt = this.newGestureEvent(EventType.Change, data.initialTarget);
evt.translationX = touch.pageX - arrays.tail(data.rollingPageX);
evt.translationY = touch.pageY - arrays.tail(data.rollingPageY);
evt.pageX = touch.pageX;
evt.pageY = touch.pageY;
this.dispatchEvent(evt);
// only keep a few data points, to average the final speed
if (data.rollingPageX.length > 3) {
data.rollingPageX.shift();
data.rollingPageY.shift();
data.rollingTimestamps.shift();
}
data.rollingPageX.push(touch.pageX);
data.rollingPageY.push(touch.pageY);
data.rollingTimestamps.push(timestamp);
}
if (this.dispatched) {
e.preventDefault();
e.stopPropagation();
this.dispatched = false;
}
}
}