mirror of
https://github.com/mozilla/gecko-dev.git
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679 lines
21 KiB
JavaScript
679 lines
21 KiB
JavaScript
/* -*- tab-width: 2; indent-tabs-mode: nil; js-indent-level: 2 -*- */
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/* vim: set ts=2 sw=2 sts=2 et: */
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/* This Source Code Form is subject to the terms of the Mozilla Public
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* License, v. 2.0. If a copy of the MPL was not distributed with this file,
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* You can obtain one at http://mozilla.org/MPL/2.0/. */
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"use strict";
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dump("############################### browserElementPanningAPZDisabled.js loaded\n");
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var { classes: Cc, interfaces: Ci, results: Cr, utils: Cu } = Components;
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Cu.import("resource://gre/modules/Services.jsm");
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Cu.import("resource://gre/modules/Geometry.jsm");
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var global = this;
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const ContentPanningAPZDisabled = {
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// Are we listening to touch or mouse events?
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watchedEventsType: '',
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// Are mouse events being delivered to this content along with touch
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// events, in violation of spec?
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hybridEvents: false,
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init: function cp_init() {
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this._setupListenersForPanning();
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},
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_setupListenersForPanning: function cp_setupListenersForPanning() {
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let events;
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if (content.TouchEvent) {
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events = ['touchstart', 'touchend', 'touchmove'];
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this.watchedEventsType = 'touch';
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#ifdef MOZ_WIDGET_GONK
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// The gonk widget backend does not deliver mouse events per
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// spec. Third-party content isn't exposed to this behavior,
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// but that behavior creates some extra work for us here.
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let appInfo = Cc["@mozilla.org/xre/app-info;1"];
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let isParentProcess =
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!appInfo || appInfo.getService(Ci.nsIXULRuntime)
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.processType == Ci.nsIXULRuntime.PROCESS_TYPE_DEFAULT;
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this.hybridEvents = isParentProcess;
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#endif
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} else {
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// Touch events aren't supported, so fall back on mouse.
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events = ['mousedown', 'mouseup', 'mousemove'];
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this.watchedEventsType = 'mouse';
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}
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let els = Cc["@mozilla.org/eventlistenerservice;1"]
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.getService(Ci.nsIEventListenerService);
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events.forEach(function(type) {
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// Using the system group for mouse/touch events to avoid
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// missing events if .stopPropagation() has been called.
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els.addSystemEventListener(global, type,
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this.handleEvent.bind(this),
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/* useCapture = */ false);
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}.bind(this));
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},
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handleEvent: function cp_handleEvent(evt) {
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// Ignore events targeting an oop <iframe mozbrowser> since those will be
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// handle by the BrowserElementPanning.js instance in the child process.
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if (evt.target instanceof Ci.nsIMozBrowserFrame) {
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return;
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}
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// For in-process <iframe mozbrowser> the events are not targetting
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// directly the container iframe element, but some node of the document.
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// So, the BrowserElementPanning instance of the system app will receive
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// the sequence of touch events, as well as the BrowserElementPanning
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// instance in the targetted app.
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// As a result, multiple mozbrowser iframes will try to interpret the
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// sequence of touch events, which may results into multiple clicks.
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let targetWindow = evt.target.ownerDocument.defaultView;
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let frameElement = targetWindow.frameElement;
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while (frameElement) {
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targetWindow = frameElement.ownerDocument.defaultView;
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frameElement = targetWindow.frameElement;
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}
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if (content !== targetWindow) {
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return;
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}
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if (evt.defaultPrevented || evt.multipleActionsPrevented) {
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// clean up panning state even if touchend/mouseup has been preventDefault.
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if(evt.type === 'touchend' || evt.type === 'mouseup') {
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if (this.dragging &&
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(this.watchedEventsType === 'mouse' ||
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this.findPrimaryPointer(evt.changedTouches))) {
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this._finishPanning();
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}
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}
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return;
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}
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switch (evt.type) {
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case 'mousedown':
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case 'touchstart':
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this.onTouchStart(evt);
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break;
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case 'mousemove':
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case 'touchmove':
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this.onTouchMove(evt);
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break;
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case 'mouseup':
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case 'touchend':
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this.onTouchEnd(evt);
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break;
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case 'click':
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evt.stopPropagation();
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evt.preventDefault();
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let target = evt.target;
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let view = target.ownerDocument ? target.ownerDocument.defaultView
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: target;
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view.removeEventListener('click', this, true, true);
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break;
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}
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},
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position: new Point(0 , 0),
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findPrimaryPointer: function cp_findPrimaryPointer(touches) {
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if (!('primaryPointerId' in this))
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return null;
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for (let i = 0; i < touches.length; i++) {
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if (touches[i].identifier === this.primaryPointerId) {
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return touches[i];
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}
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}
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return null;
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},
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onTouchStart: function cp_onTouchStart(evt) {
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let screenX, screenY;
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if (this.watchedEventsType == 'touch') {
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if ('primaryPointerId' in this || evt.touches.length >= 2) {
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this._resetActive();
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return;
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}
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let firstTouch = evt.changedTouches[0];
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this.primaryPointerId = firstTouch.identifier;
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this.pointerDownTarget = firstTouch.target;
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screenX = firstTouch.screenX;
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screenY = firstTouch.screenY;
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} else {
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this.pointerDownTarget = evt.target;
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screenX = evt.screenX;
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screenY = evt.screenY;
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}
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this.dragging = true;
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this.panning = false;
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let oldTarget = this.target;
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[this.target, this.scrollCallback] = this.getPannable(this.pointerDownTarget);
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// If we have a pointer down target, we may need to fill in for EventStateManager
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// in setting the active state on the target element. Set a timer to
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// ensure the pointer-down target is active. (If it's already
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// active, the timer is a no-op.)
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if (this.pointerDownTarget !== null) {
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// If there's no possibility this is a drag/pan, activate now.
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// Otherwise wait a little bit to see if the gesture isn't a
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// tap.
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if (this.target === null) {
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this.notify(this._activationTimer);
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} else {
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this._activationTimer.initWithCallback(this,
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this._activationDelayMs,
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Ci.nsITimer.TYPE_ONE_SHOT);
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}
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}
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// If there is a pan animation running (from a previous pan gesture) and
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// the user touch back the screen, stop this animation immediatly and
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// prevent the possible click action if the touch happens on the same
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// target.
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this.preventNextClick = false;
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if (KineticPanning.active) {
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KineticPanning.stop();
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if (oldTarget && oldTarget == this.target)
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this.preventNextClick = true;
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}
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this.position.set(screenX, screenY);
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KineticPanning.reset();
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KineticPanning.record(new Point(0, 0), evt.timeStamp);
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// We prevent start events to avoid sending a focus event at the end of this
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// touch series. See bug 889717.
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if ((this.panning || this.preventNextClick)) {
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evt.preventDefault();
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}
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},
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onTouchEnd: function cp_onTouchEnd(evt) {
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let touch = null;
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if (!this.dragging ||
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(this.watchedEventsType == 'touch' &&
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!(touch = this.findPrimaryPointer(evt.changedTouches)))) {
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return;
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}
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// !isPan() and evt.detail should always give the same answer here
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// since they use the same heuristics, but use the native gecko
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// computation when possible.
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//
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// NB: when we're using touch events, then !KineticPanning.isPan()
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// => this.panning, so we'll never attempt to block the click
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// event. That's OK however, because we won't fire a synthetic
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// click when we're using touch events and this touch series
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// wasn't a "tap" gesture.
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let click = (this.watchedEventsType == 'mouse') ?
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evt.detail : !KineticPanning.isPan();
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// Additionally, if we're seeing non-compliant hybrid events, a
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// "real" click will be generated if we started and ended on the
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// same element.
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if (this.hybridEvents) {
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let target =
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content.document.elementFromPoint(touch.clientX, touch.clientY);
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click |= (target === this.pointerDownTarget);
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}
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if (this.target && click && (this.panning || this.preventNextClick)) {
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if (this.hybridEvents) {
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let target = this.target;
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let view = target.ownerDocument ? target.ownerDocument.defaultView
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: target;
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view.addEventListener('click', this, true, true);
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} else {
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// We prevent end events to avoid sending a focus event. See bug 889717.
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evt.preventDefault();
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}
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} else if (this.target && click && !this.panning) {
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this.notify(this._activationTimer);
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}
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this._finishPanning();
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// Now that we're done, avoid entraining the thing we just panned.
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this.pointerDownTarget = null;
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},
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onTouchMove: function cp_onTouchMove(evt) {
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if (!this.dragging)
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return;
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let screenX, screenY;
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if (this.watchedEventsType == 'touch') {
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let primaryTouch = this.findPrimaryPointer(evt.changedTouches);
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if (evt.touches.length > 1 || !primaryTouch)
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return;
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screenX = primaryTouch.screenX;
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screenY = primaryTouch.screenY;
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} else {
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screenX = evt.screenX;
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screenY = evt.screenY;
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}
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let current = this.position;
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let delta = new Point(screenX - current.x, screenY - current.y);
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current.set(screenX, screenY);
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KineticPanning.record(delta, evt.timeStamp);
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let isPan = KineticPanning.isPan();
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// If we've detected a pan gesture, cancel the active state of the
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// current target.
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if (!this.panning && isPan) {
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this._resetActive();
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}
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// There's no possibility of us panning anything.
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if (!this.scrollCallback) {
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return;
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}
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// Scroll manually.
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this.scrollCallback(delta.scale(-1));
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if (!this.panning && isPan) {
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this.panning = true;
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this._activationTimer.cancel();
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}
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if (this.panning) {
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// Only do this when we're actually executing a pan gesture.
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// Otherwise synthetic mouse events will be canceled.
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evt.stopPropagation();
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evt.preventDefault();
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}
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},
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// nsITimerCallback
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notify: function cp_notify(timer) {
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this._setActive(this.pointerDownTarget);
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},
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onKineticBegin: function cp_onKineticBegin(evt) {
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},
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onKineticPan: function cp_onKineticPan(delta) {
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return !this.scrollCallback(delta);
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},
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onKineticEnd: function cp_onKineticEnd() {
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if (!this.dragging)
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this.scrollCallback = null;
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},
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getPannable: function cp_getPannable(node) {
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let pannableNode = this._findPannable(node);
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if (pannableNode) {
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return [pannableNode, this._generateCallback(pannableNode)];
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}
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return [null, null];
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},
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_findPannable: function cp_findPannable(node) {
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if (!(node instanceof Ci.nsIDOMHTMLElement) || node.tagName == 'HTML') {
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return null;
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}
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let nodeContent = node.ownerDocument.defaultView;
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while (!(node instanceof Ci.nsIDOMHTMLBodyElement)) {
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let style = nodeContent.getComputedStyle(node, null);
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let overflow = [style.getPropertyValue('overflow'),
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style.getPropertyValue('overflow-x'),
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style.getPropertyValue('overflow-y')];
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let rect = node.getBoundingClientRect();
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let isAuto = (overflow.indexOf('auto') != -1 &&
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(rect.height < node.scrollHeight ||
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rect.width < node.scrollWidth));
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let isScroll = (overflow.indexOf('scroll') != -1);
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let isScrollableTextarea = (node.tagName == 'TEXTAREA' &&
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(node.scrollHeight > node.clientHeight ||
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node.scrollWidth > node.clientWidth ||
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('scrollLeftMin' in node && 'scrollLeftMax' in node &&
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node.scrollLeftMin != node.scrollLeftMax) ||
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('scrollTopMin' in node && 'scrollTopMax' in node &&
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node.scrollTopMin != node.scrollTopMax)));
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if (isScroll || isAuto || isScrollableTextarea) {
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return node;
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}
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node = node.parentNode;
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}
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if (nodeContent.scrollMaxX != nodeContent.scrollMinX ||
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nodeContent.scrollMaxY != nodeContent.scrollMinY) {
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return nodeContent;
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}
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if (nodeContent.frameElement) {
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return this._findPannable(nodeContent.frameElement);
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}
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return null;
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},
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_generateCallback: function cp_generateCallback(root) {
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let firstScroll = true;
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let target;
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let current;
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let win, doc, htmlNode, bodyNode;
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function doScroll(node, delta) {
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if (node instanceof Ci.nsIDOMHTMLElement) {
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return node.scrollByNoFlush(delta.x, delta.y);
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} else if (node instanceof Ci.nsIDOMWindow) {
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win = node;
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doc = win.document;
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// "overflow:hidden" on either the <html> or the <body> node should
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// prevent the user from scrolling the root viewport.
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if (doc instanceof Ci.nsIDOMHTMLDocument) {
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htmlNode = doc.documentElement;
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bodyNode = doc.body;
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if (win.getComputedStyle(htmlNode, null).overflowX == "hidden" ||
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win.getComputedStyle(bodyNode, null).overflowX == "hidden") {
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delta.x = 0;
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}
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if (win.getComputedStyle(htmlNode, null).overflowY == "hidden" ||
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win.getComputedStyle(bodyNode, null).overflowY == "hidden") {
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delta.y = 0;
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}
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}
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let oldX = node.scrollX;
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let oldY = node.scrollY;
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node.scrollBy(delta.x, delta.y);
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return (node.scrollX != oldX || node.scrollY != oldY);
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}
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// If we get here, |node| isn't an HTML element and it's not a window,
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// but findPannable apparently thought it was scrollable... What is it?
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return false;
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}
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function targetParent(node) {
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return node.parentNode || node.frameElement || null;
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}
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function scroll(delta) {
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current = root;
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firstScroll = true;
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while (current) {
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if (doScroll(current, delta)) {
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firstScroll = false;
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return true;
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}
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// TODO The current code looks for possible scrolling regions only if
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// this is the first scroll action but this should be more dynamic.
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if (!firstScroll) {
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return false;
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}
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current = ContentPanningAPZDisabled._findPannable(targetParent(current));
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}
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// There is nothing scrollable here.
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return false;
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}
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return scroll;
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},
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get _activationTimer() {
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delete this._activationTimer;
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return this._activationTimer = Cc["@mozilla.org/timer;1"]
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.createInstance(Ci.nsITimer);
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},
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get _activationDelayMs() {
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let delay = Services.prefs.getIntPref('ui.touch_activation.delay_ms');
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delete this._activationDelayMs;
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return this._activationDelayMs = delay;
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},
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get _domUtils() {
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delete this._domUtils;
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return this._domUtils = Cc['@mozilla.org/inspector/dom-utils;1']
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.getService(Ci.inIDOMUtils);
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},
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_resetActive: function cp_resetActive() {
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let elt = this.pointerDownTarget || this.target;
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let root = elt.ownerDocument || elt.document;
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this._setActive(root.documentElement);
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},
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_setActive: function cp_setActive(elt) {
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const kStateActive = 0x00000001;
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this._domUtils.setContentState(elt, kStateActive);
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},
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_finishPanning: function() {
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this.dragging = false;
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delete this.primaryPointerId;
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this._activationTimer.cancel();
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// If there is a scroll action, let's do a manual kinetic panning action.
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if (this.panning) {
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KineticPanning.start(this);
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}
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},
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};
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// Min/max velocity of kinetic panning. This is in pixels/millisecond.
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const kMinVelocity = 0.2;
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const kMaxVelocity = 6;
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// Constants that affect the "friction" of the scroll pane.
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const kExponentialC = 1000;
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const kPolynomialC = 100 / 1000000;
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// How often do we change the position of the scroll pane?
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// Too often and panning may jerk near the end.
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// Too little and panning will be choppy. In milliseconds.
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const kUpdateInterval = 16;
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// The numbers of momentums to use for calculating the velocity of the pan.
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// Those are taken from the end of the action
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const kSamples = 5;
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const KineticPanning = {
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_position: new Point(0, 0),
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_velocity: new Point(0, 0),
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_acceleration: new Point(0, 0),
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get active() {
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return this.target !== null;
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},
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target: null,
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start: function kp_start(target) {
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this.target = target;
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// Calculate the initial velocity of the movement based on user input
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let momentums = this.momentums;
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let flick = momentums[momentums.length - 1].time - momentums[0].time < 300;
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let distance = new Point(0, 0);
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momentums.forEach(function(momentum) {
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distance.add(momentum.dx, momentum.dy);
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});
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function clampFromZero(x, min, max) {
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if (x >= 0)
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return Math.max(min, Math.min(max, x));
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return Math.min(-min, Math.max(-max, x));
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}
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let elapsed = momentums[momentums.length - 1].time - momentums[0].time;
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let velocityX = clampFromZero(distance.x / elapsed, 0, kMaxVelocity);
|
|
let velocityY = clampFromZero(distance.y / elapsed, 0, kMaxVelocity);
|
|
|
|
let velocity = this._velocity;
|
|
if (flick) {
|
|
// Very fast pan action that does not generate a click are very often pan
|
|
// action. If this is a small gesture then it will not move the view a lot
|
|
// and so it will be above the minimun threshold and not generate any
|
|
// kinetic panning. This does not look on a device since this is often
|
|
// a real gesture, so let's lower the velocity threshold for such moves.
|
|
velocity.set(velocityX, velocityY);
|
|
} else {
|
|
velocity.set(Math.abs(velocityX) < kMinVelocity ? 0 : velocityX,
|
|
Math.abs(velocityY) < kMinVelocity ? 0 : velocityY);
|
|
}
|
|
this.momentums = [];
|
|
|
|
// Set acceleration vector to opposite signs of velocity
|
|
function sign(x) {
|
|
return x ? (x > 0 ? 1 : -1) : 0;
|
|
}
|
|
|
|
this._acceleration.set(velocity.clone().map(sign).scale(-kPolynomialC));
|
|
|
|
// Reset the position
|
|
this._position.set(0, 0);
|
|
|
|
this._startAnimation();
|
|
|
|
this.target.onKineticBegin();
|
|
},
|
|
|
|
stop: function kp_stop() {
|
|
this.reset();
|
|
|
|
if (!this.target)
|
|
return;
|
|
|
|
this.target.onKineticEnd();
|
|
this.target = null;
|
|
},
|
|
|
|
reset: function kp_reset() {
|
|
this.momentums = [];
|
|
this.distance.set(0, 0);
|
|
},
|
|
|
|
momentums: [],
|
|
record: function kp_record(delta, timestamp) {
|
|
this.momentums.push({ 'time': this._getTime(timestamp),
|
|
'dx' : delta.x, 'dy' : delta.y });
|
|
|
|
// We only need to keep kSamples in this.momentums.
|
|
if (this.momentums.length > kSamples) {
|
|
this.momentums.shift();
|
|
}
|
|
|
|
this.distance.add(delta.x, delta.y);
|
|
},
|
|
|
|
_getTime: function kp_getTime(time) {
|
|
// Touch events generated by the platform or hand-made are defined in
|
|
// microseconds instead of milliseconds. Bug 77992 will fix this at the
|
|
// platform level.
|
|
if (time > Date.now()) {
|
|
return Math.floor(time / 1000);
|
|
} else {
|
|
return time;
|
|
}
|
|
},
|
|
|
|
get threshold() {
|
|
let dpi = content.QueryInterface(Ci.nsIInterfaceRequestor)
|
|
.getInterface(Ci.nsIDOMWindowUtils)
|
|
.displayDPI;
|
|
|
|
let threshold = Services.prefs.getIntPref('ui.dragThresholdX') / 240 * dpi;
|
|
|
|
delete this.threshold;
|
|
return this.threshold = threshold;
|
|
},
|
|
|
|
distance: new Point(0, 0),
|
|
isPan: function cp_isPan() {
|
|
return (Math.abs(this.distance.x) > this.threshold ||
|
|
Math.abs(this.distance.y) > this.threshold);
|
|
},
|
|
|
|
_startAnimation: function kp_startAnimation() {
|
|
let c = kExponentialC;
|
|
function getNextPosition(position, v, a, t) {
|
|
// Important traits for this function:
|
|
// p(t=0) is 0
|
|
// p'(t=0) is v0
|
|
//
|
|
// We use exponential to get a smoother stop, but by itself exponential
|
|
// is too smooth at the end. Adding a polynomial with the appropriate
|
|
// weight helps to balance
|
|
position.set(v.x * Math.exp(-t / c) * -c + a.x * t * t + v.x * c,
|
|
v.y * Math.exp(-t / c) * -c + a.y * t * t + v.y * c);
|
|
}
|
|
|
|
let startTime = content.performance.now();
|
|
let elapsedTime = 0, targetedTime = 0, averageTime = 0;
|
|
|
|
let velocity = this._velocity;
|
|
let acceleration = this._acceleration;
|
|
|
|
let position = this._position;
|
|
let nextPosition = new Point(0, 0);
|
|
let delta = new Point(0, 0);
|
|
|
|
let callback = (function(timestamp) {
|
|
if (!this.target)
|
|
return;
|
|
|
|
// To make animation end fast enough but to keep smoothness, average the
|
|
// ideal time frame (smooth animation) with the actual time lapse
|
|
// (end fast enough).
|
|
// Animation will never take longer than 2 times the ideal length of time.
|
|
elapsedTime = timestamp - startTime;
|
|
targetedTime += kUpdateInterval;
|
|
averageTime = (targetedTime + elapsedTime) / 2;
|
|
|
|
// Calculate new position.
|
|
getNextPosition(nextPosition, velocity, acceleration, averageTime);
|
|
delta.set(Math.round(nextPosition.x - position.x),
|
|
Math.round(nextPosition.y - position.y));
|
|
|
|
// Test to see if movement is finished for each component.
|
|
if (delta.x * acceleration.x > 0)
|
|
delta.x = position.x = velocity.x = acceleration.x = 0;
|
|
|
|
if (delta.y * acceleration.y > 0)
|
|
delta.y = position.y = velocity.y = acceleration.y = 0;
|
|
|
|
if (velocity.equals(0, 0) || delta.equals(0, 0)) {
|
|
this.stop();
|
|
return;
|
|
}
|
|
|
|
position.add(delta);
|
|
if (this.target.onKineticPan(delta.scale(-1))) {
|
|
this.stop();
|
|
return;
|
|
}
|
|
|
|
content.requestAnimationFrame(callback);
|
|
}).bind(this);
|
|
|
|
content.requestAnimationFrame(callback);
|
|
}
|
|
};
|