summaryrefslogtreecommitdiffstats
path: root/toolkit/content/widgets/arrowscrollbox.js
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 00:47:55 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 00:47:55 +0000
commit26a029d407be480d791972afb5975cf62c9360a6 (patch)
treef435a8308119effd964b339f76abb83a57c29483 /toolkit/content/widgets/arrowscrollbox.js
parentInitial commit. (diff)
downloadfirefox-26a029d407be480d791972afb5975cf62c9360a6.tar.xz
firefox-26a029d407be480d791972afb5975cf62c9360a6.zip
Adding upstream version 124.0.1.upstream/124.0.1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'toolkit/content/widgets/arrowscrollbox.js')
-rw-r--r--toolkit/content/widgets/arrowscrollbox.js868
1 files changed, 868 insertions, 0 deletions
diff --git a/toolkit/content/widgets/arrowscrollbox.js b/toolkit/content/widgets/arrowscrollbox.js
new file mode 100644
index 0000000000..28de96c8d7
--- /dev/null
+++ b/toolkit/content/widgets/arrowscrollbox.js
@@ -0,0 +1,868 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+// This is loaded into all XUL windows. Wrap in a block to prevent
+// leaking to window scope.
+{
+ class MozArrowScrollbox extends MozElements.BaseControl {
+ static get inheritedAttributes() {
+ return {
+ "#scrollbutton-up": "disabled=scrolledtostart",
+ ".scrollbox-clip": "orient",
+ scrollbox: "orient,align,pack,dir,smoothscroll",
+ "#scrollbutton-down": "disabled=scrolledtoend",
+ };
+ }
+
+ get markup() {
+ return `
+ <html:link rel="stylesheet" href="chrome://global/skin/toolbarbutton.css"/>
+ <html:link rel="stylesheet" href="chrome://global/skin/arrowscrollbox.css"/>
+ <toolbarbutton id="scrollbutton-up" part="scrollbutton-up" keyNav="false"/>
+ <spacer part="overflow-start-indicator"/>
+ <box class="scrollbox-clip" part="scrollbox-clip" flex="1">
+ <scrollbox part="scrollbox" flex="1">
+ <html:slot/>
+ </scrollbox>
+ </box>
+ <spacer part="overflow-end-indicator"/>
+ <toolbarbutton id="scrollbutton-down" part="scrollbutton-down" keyNav="false"/>
+ `;
+ }
+
+ constructor() {
+ super();
+ this.attachShadow({ mode: "open" });
+ this.shadowRoot.appendChild(this.fragment);
+
+ this.scrollbox = this.shadowRoot.querySelector("scrollbox");
+ this._scrollButtonUp = this.shadowRoot.getElementById("scrollbutton-up");
+ this._scrollButtonDown =
+ this.shadowRoot.getElementById("scrollbutton-down");
+
+ this._arrowScrollAnim = {
+ scrollbox: this,
+ requestHandle: 0,
+ /* 0 indicates there is no pending request */
+ start: function arrowSmoothScroll_start() {
+ this.lastFrameTime = window.performance.now();
+ if (!this.requestHandle) {
+ this.requestHandle = window.requestAnimationFrame(
+ this.sample.bind(this)
+ );
+ }
+ },
+ stop: function arrowSmoothScroll_stop() {
+ window.cancelAnimationFrame(this.requestHandle);
+ this.requestHandle = 0;
+ },
+ sample: function arrowSmoothScroll_handleEvent(timeStamp) {
+ const scrollIndex = this.scrollbox._scrollIndex;
+ const timePassed = timeStamp - this.lastFrameTime;
+ this.lastFrameTime = timeStamp;
+
+ const scrollDelta = 0.5 * timePassed * scrollIndex;
+ this.scrollbox.scrollByPixels(scrollDelta, true);
+ this.requestHandle = window.requestAnimationFrame(
+ this.sample.bind(this)
+ );
+ },
+ };
+
+ this._scrollIndex = 0;
+ this._scrollIncrement = null;
+ this._ensureElementIsVisibleAnimationFrame = 0;
+ this._prevMouseScrolls = [null, null];
+ this._touchStart = -1;
+ this._scrollButtonUpdatePending = false;
+ this._isScrolling = false;
+ this._destination = 0;
+ this._direction = 0;
+
+ this.addEventListener("wheel", this.on_wheel);
+ this.addEventListener("touchstart", this.on_touchstart);
+ this.addEventListener("touchmove", this.on_touchmove);
+ this.addEventListener("touchend", this.on_touchend);
+ this.shadowRoot.addEventListener("click", this.on_click.bind(this));
+ this.shadowRoot.addEventListener(
+ "mousedown",
+ this.on_mousedown.bind(this)
+ );
+ this.shadowRoot.addEventListener(
+ "mouseover",
+ this.on_mouseover.bind(this)
+ );
+ this.shadowRoot.addEventListener("mouseup", this.on_mouseup.bind(this));
+ this.shadowRoot.addEventListener("mouseout", this.on_mouseout.bind(this));
+
+ // These events don't get retargeted outside of the shadow root, but
+ // some callers like tests wait for these events. So run handlers
+ // and then retarget events from the scrollbox to the host.
+ this.scrollbox.addEventListener(
+ "underflow",
+ event => {
+ this.on_underflow(event);
+ this.dispatchEvent(new Event("underflow"));
+ },
+ true
+ );
+ this.scrollbox.addEventListener(
+ "overflow",
+ event => {
+ this.on_overflow(event);
+ this.dispatchEvent(new Event("overflow"));
+ },
+ true
+ );
+ this.scrollbox.addEventListener("scroll", event => {
+ this.on_scroll(event);
+ this.dispatchEvent(new Event("scroll"));
+ });
+
+ this.scrollbox.addEventListener("scrollend", event => {
+ this.on_scrollend(event);
+ this.dispatchEvent(new Event("scrollend"));
+ });
+ }
+
+ connectedCallback() {
+ if (this.hasConnected) {
+ return;
+ }
+ this.hasConnected = true;
+
+ if (!this.hasAttribute("smoothscroll")) {
+ this.smoothScroll = Services.prefs.getBoolPref(
+ "toolkit.scrollbox.smoothScroll",
+ true
+ );
+ }
+
+ this.removeAttribute("overflowing");
+ this.initializeAttributeInheritance();
+ this._updateScrollButtonsDisabledState();
+ }
+
+ get fragment() {
+ if (!this.constructor.hasOwnProperty("_fragment")) {
+ this.constructor._fragment = MozXULElement.parseXULToFragment(
+ this.markup
+ );
+ }
+ return document.importNode(this.constructor._fragment, true);
+ }
+
+ get _clickToScroll() {
+ return this.hasAttribute("clicktoscroll");
+ }
+
+ get _scrollDelay() {
+ if (this._clickToScroll) {
+ return Services.prefs.getIntPref(
+ "toolkit.scrollbox.clickToScroll.scrollDelay",
+ 150
+ );
+ }
+
+ // Use the same REPEAT_DELAY as "nsRepeatService.h".
+ return /Mac/.test(navigator.platform) ? 25 : 50;
+ }
+
+ get scrollIncrement() {
+ if (this._scrollIncrement === null) {
+ this._scrollIncrement = Services.prefs.getIntPref(
+ "toolkit.scrollbox.scrollIncrement",
+ 20
+ );
+ }
+ return this._scrollIncrement;
+ }
+
+ set smoothScroll(val) {
+ this.setAttribute("smoothscroll", !!val);
+ }
+
+ get smoothScroll() {
+ return this.getAttribute("smoothscroll") == "true";
+ }
+
+ get scrollClientRect() {
+ return this.scrollbox.getBoundingClientRect();
+ }
+
+ get scrollClientSize() {
+ return this.getAttribute("orient") == "vertical"
+ ? this.scrollbox.clientHeight
+ : this.scrollbox.clientWidth;
+ }
+
+ get scrollSize() {
+ return this.getAttribute("orient") == "vertical"
+ ? this.scrollbox.scrollHeight
+ : this.scrollbox.scrollWidth;
+ }
+
+ get lineScrollAmount() {
+ // line scroll amout should be the width (at horizontal scrollbox) or
+ // the height (at vertical scrollbox) of the scrolled elements.
+ // However, the elements may have different width or height. So,
+ // for consistent speed, let's use average width of the elements.
+ var elements = this._getScrollableElements();
+ return elements.length && this.scrollSize / elements.length;
+ }
+
+ get scrollPosition() {
+ return this.getAttribute("orient") == "vertical"
+ ? this.scrollbox.scrollTop
+ : this.scrollbox.scrollLeft;
+ }
+
+ get startEndProps() {
+ if (!this._startEndProps) {
+ this._startEndProps =
+ this.getAttribute("orient") == "vertical"
+ ? ["top", "bottom"]
+ : ["left", "right"];
+ }
+ return this._startEndProps;
+ }
+
+ get isRTLScrollbox() {
+ if (!this._isRTLScrollbox) {
+ this._isRTLScrollbox =
+ this.getAttribute("orient") != "vertical" &&
+ document.defaultView.getComputedStyle(this.scrollbox).direction ==
+ "rtl";
+ }
+ return this._isRTLScrollbox;
+ }
+
+ _onButtonClick(event) {
+ if (this._clickToScroll) {
+ this._distanceScroll(event);
+ }
+ }
+
+ _onButtonMouseDown(event, index) {
+ if (this._clickToScroll && event.button == 0) {
+ this._startScroll(index);
+ }
+ }
+
+ _onButtonMouseUp(event) {
+ if (this._clickToScroll && event.button == 0) {
+ this._stopScroll();
+ }
+ }
+
+ _onButtonMouseOver(index) {
+ if (this._clickToScroll) {
+ this._continueScroll(index);
+ } else {
+ this._startScroll(index);
+ }
+ }
+
+ _onButtonMouseOut() {
+ if (this._clickToScroll) {
+ this._pauseScroll();
+ } else {
+ this._stopScroll();
+ }
+ }
+
+ _boundsWithoutFlushing(element) {
+ if (!("_DOMWindowUtils" in this)) {
+ this._DOMWindowUtils = window.windowUtils;
+ }
+
+ return this._DOMWindowUtils
+ ? this._DOMWindowUtils.getBoundsWithoutFlushing(element)
+ : element.getBoundingClientRect();
+ }
+
+ _canScrollToElement(element) {
+ if (element.hidden) {
+ return false;
+ }
+
+ // See if the element is hidden via CSS without the hidden attribute.
+ // If we get only zeros for the client rect, this means the element
+ // is hidden. As a performance optimization, we don't flush layout
+ // here which means that on the fly changes aren't fully supported.
+ let rect = this._boundsWithoutFlushing(element);
+ return !!(rect.top || rect.left || rect.width || rect.height);
+ }
+
+ ensureElementIsVisible(element, aInstant) {
+ if (!this._canScrollToElement(element)) {
+ return;
+ }
+
+ if (this._ensureElementIsVisibleAnimationFrame) {
+ window.cancelAnimationFrame(this._ensureElementIsVisibleAnimationFrame);
+ }
+ this._ensureElementIsVisibleAnimationFrame = window.requestAnimationFrame(
+ () => {
+ element.scrollIntoView({
+ block: "nearest",
+ behavior: aInstant ? "instant" : "auto",
+ });
+ this._ensureElementIsVisibleAnimationFrame = 0;
+ }
+ );
+ }
+
+ scrollByIndex(index, aInstant) {
+ if (index == 0) {
+ return;
+ }
+
+ var rect = this.scrollClientRect;
+ var [start, end] = this.startEndProps;
+ var x = index > 0 ? rect[end] + 1 : rect[start] - 1;
+ var nextElement = this._elementFromPoint(x, index);
+ if (!nextElement) {
+ return;
+ }
+
+ var targetElement;
+ if (this.isRTLScrollbox) {
+ index *= -1;
+ }
+ while (index < 0 && nextElement) {
+ if (this._canScrollToElement(nextElement)) {
+ targetElement = nextElement;
+ }
+ nextElement = nextElement.previousElementSibling;
+ index++;
+ }
+ while (index > 0 && nextElement) {
+ if (this._canScrollToElement(nextElement)) {
+ targetElement = nextElement;
+ }
+ nextElement = nextElement.nextElementSibling;
+ index--;
+ }
+ if (!targetElement) {
+ return;
+ }
+
+ this.ensureElementIsVisible(targetElement, aInstant);
+ }
+
+ _getScrollableElements() {
+ let nodes = this.children;
+ if (nodes.length == 1) {
+ let node = nodes[0];
+ if (
+ node.localName == "slot" &&
+ node.namespaceURI == "http://www.w3.org/1999/xhtml"
+ ) {
+ nodes = node.getRootNode().host.children;
+ }
+ }
+ return Array.prototype.filter.call(nodes, this._canScrollToElement, this);
+ }
+
+ _elementFromPoint(aX, aPhysicalScrollDir) {
+ var elements = this._getScrollableElements();
+ if (!elements.length) {
+ return null;
+ }
+
+ if (this.isRTLScrollbox) {
+ elements.reverse();
+ }
+
+ var [start, end] = this.startEndProps;
+ var low = 0;
+ var high = elements.length - 1;
+
+ if (
+ aX < elements[low].getBoundingClientRect()[start] ||
+ aX > elements[high].getBoundingClientRect()[end]
+ ) {
+ return null;
+ }
+
+ var mid, rect;
+ while (low <= high) {
+ mid = Math.floor((low + high) / 2);
+ rect = elements[mid].getBoundingClientRect();
+ if (rect[start] > aX) {
+ high = mid - 1;
+ } else if (rect[end] < aX) {
+ low = mid + 1;
+ } else {
+ return elements[mid];
+ }
+ }
+
+ // There's no element at the requested coordinate, but the algorithm
+ // from above yields an element next to it, in a random direction.
+ // The desired scrolling direction leads to the correct element.
+
+ if (!aPhysicalScrollDir) {
+ return null;
+ }
+
+ if (aPhysicalScrollDir < 0 && rect[start] > aX) {
+ mid = Math.max(mid - 1, 0);
+ } else if (aPhysicalScrollDir > 0 && rect[end] < aX) {
+ mid = Math.min(mid + 1, elements.length - 1);
+ }
+
+ return elements[mid];
+ }
+
+ _startScroll(index) {
+ if (this.isRTLScrollbox) {
+ index *= -1;
+ }
+
+ if (this._clickToScroll) {
+ this._scrollIndex = index;
+ this._mousedown = true;
+
+ if (this.smoothScroll) {
+ this._arrowScrollAnim.start();
+ return;
+ }
+ }
+
+ if (!this._scrollTimer) {
+ this._scrollTimer = Cc["@mozilla.org/timer;1"].createInstance(
+ Ci.nsITimer
+ );
+ } else {
+ this._scrollTimer.cancel();
+ }
+
+ let callback;
+ if (this._clickToScroll) {
+ callback = () => {
+ if (!document && this._scrollTimer) {
+ this._scrollTimer.cancel();
+ }
+ this.scrollByIndex(this._scrollIndex);
+ };
+ } else {
+ callback = () => this.scrollByPixels(this.scrollIncrement * index);
+ }
+
+ this._scrollTimer.initWithCallback(
+ callback,
+ this._scrollDelay,
+ Ci.nsITimer.TYPE_REPEATING_SLACK
+ );
+
+ callback();
+ }
+
+ _stopScroll() {
+ if (this._scrollTimer) {
+ this._scrollTimer.cancel();
+ }
+
+ if (this._clickToScroll) {
+ this._mousedown = false;
+ if (!this._scrollIndex || !this.smoothScroll) {
+ return;
+ }
+
+ this.scrollByIndex(this._scrollIndex);
+ this._scrollIndex = 0;
+
+ this._arrowScrollAnim.stop();
+ }
+ }
+
+ _pauseScroll() {
+ if (this._mousedown) {
+ this._stopScroll();
+ this._mousedown = true;
+ document.addEventListener("mouseup", this);
+ document.addEventListener("blur", this, true);
+ }
+ }
+
+ _continueScroll(index) {
+ if (this._mousedown) {
+ this._startScroll(index);
+ }
+ }
+
+ _distanceScroll(aEvent) {
+ if (aEvent.detail < 2 || aEvent.detail > 3) {
+ return;
+ }
+
+ var scrollBack = aEvent.originalTarget == this._scrollButtonUp;
+ var scrollLeftOrUp = this.isRTLScrollbox ? !scrollBack : scrollBack;
+ var targetElement;
+
+ if (aEvent.detail == 2) {
+ // scroll by the size of the scrollbox
+ let [start, end] = this.startEndProps;
+ let x;
+ if (scrollLeftOrUp) {
+ x = this.scrollClientRect[start] - this.scrollClientSize;
+ } else {
+ x = this.scrollClientRect[end] + this.scrollClientSize;
+ }
+ targetElement = this._elementFromPoint(x, scrollLeftOrUp ? -1 : 1);
+
+ // the next partly-hidden element will become fully visible,
+ // so don't scroll too far
+ if (targetElement) {
+ targetElement = scrollBack
+ ? targetElement.nextElementSibling
+ : targetElement.previousElementSibling;
+ }
+ }
+
+ if (!targetElement) {
+ // scroll to the first resp. last element
+ let elements = this._getScrollableElements();
+ targetElement = scrollBack
+ ? elements[0]
+ : elements[elements.length - 1];
+ }
+
+ this.ensureElementIsVisible(targetElement);
+ }
+
+ handleEvent(aEvent) {
+ if (
+ aEvent.type == "mouseup" ||
+ (aEvent.type == "blur" && aEvent.target == document)
+ ) {
+ this._mousedown = false;
+ document.removeEventListener("mouseup", this);
+ document.removeEventListener("blur", this, true);
+ }
+ }
+
+ scrollByPixels(aPixels, aInstant) {
+ let scrollOptions = { behavior: aInstant ? "instant" : "auto" };
+ scrollOptions[this.startEndProps[0]] = aPixels;
+ this.scrollbox.scrollBy(scrollOptions);
+ }
+
+ _updateScrollButtonsDisabledState() {
+ if (!this.hasAttribute("overflowing")) {
+ this.setAttribute("scrolledtoend", "true");
+ this.setAttribute("scrolledtostart", "true");
+ return;
+ }
+
+ if (this._scrollButtonUpdatePending) {
+ return;
+ }
+ this._scrollButtonUpdatePending = true;
+
+ // Wait until after the next paint to get current layout data from
+ // getBoundsWithoutFlushing.
+ window.requestAnimationFrame(() => {
+ setTimeout(() => {
+ if (!this.isConnected) {
+ // We've been destroyed in the meantime.
+ return;
+ }
+
+ this._scrollButtonUpdatePending = false;
+
+ let scrolledToStart = false;
+ let scrolledToEnd = false;
+
+ if (!this.hasAttribute("overflowing")) {
+ scrolledToStart = true;
+ scrolledToEnd = true;
+ } else {
+ let isAtEdge = (element, start) => {
+ let edge = start ? this.startEndProps[0] : this.startEndProps[1];
+ let scrollEdge = this._boundsWithoutFlushing(this.scrollbox)[
+ edge
+ ];
+ let elementEdge = this._boundsWithoutFlushing(element)[edge];
+ // This is enough slop (>2/3) so that no subpixel value should
+ // get us confused about whether we reached the end.
+ const EPSILON = 0.7;
+ if (start) {
+ return scrollEdge <= elementEdge + EPSILON;
+ }
+ return elementEdge <= scrollEdge + EPSILON;
+ };
+
+ let elements = this._getScrollableElements();
+ let [startElement, endElement] = [
+ elements[0],
+ elements[elements.length - 1],
+ ];
+ if (this.isRTLScrollbox) {
+ [startElement, endElement] = [endElement, startElement];
+ }
+ scrolledToStart =
+ startElement && isAtEdge(startElement, /* start = */ true);
+ scrolledToEnd =
+ endElement && isAtEdge(endElement, /* start = */ false);
+ if (this.isRTLScrollbox) {
+ [scrolledToStart, scrolledToEnd] = [
+ scrolledToEnd,
+ scrolledToStart,
+ ];
+ }
+ }
+
+ if (scrolledToEnd) {
+ this.setAttribute("scrolledtoend", "true");
+ } else {
+ this.removeAttribute("scrolledtoend");
+ }
+
+ if (scrolledToStart) {
+ this.setAttribute("scrolledtostart", "true");
+ } else {
+ this.removeAttribute("scrolledtostart");
+ }
+ }, 0);
+ });
+ }
+
+ disconnectedCallback() {
+ // Release timer to avoid reference cycles.
+ if (this._scrollTimer) {
+ this._scrollTimer.cancel();
+ this._scrollTimer = null;
+ }
+ }
+
+ on_wheel(event) {
+ // Don't consume the event if we can't scroll.
+ if (!this.hasAttribute("overflowing")) {
+ return;
+ }
+
+ const { deltaMode } = event;
+ let doScroll = false;
+ let instant;
+ let scrollAmount = 0;
+ if (this.getAttribute("orient") == "vertical") {
+ doScroll = true;
+ scrollAmount = event.deltaY;
+ } else {
+ // We allow vertical scrolling to scroll a horizontal scrollbox
+ // because many users have a vertical scroll wheel but no
+ // horizontal support.
+ // Because of this, we need to avoid scrolling chaos on trackpads
+ // and mouse wheels that support simultaneous scrolling in both axes.
+ // We do this by scrolling only when the last two scroll events were
+ // on the same axis as the current scroll event.
+ // For diagonal scroll events we only respect the dominant axis.
+ let isVertical = Math.abs(event.deltaY) > Math.abs(event.deltaX);
+ let delta = isVertical ? event.deltaY : event.deltaX;
+ let scrollByDelta = isVertical && this.isRTLScrollbox ? -delta : delta;
+
+ if (this._prevMouseScrolls.every(prev => prev == isVertical)) {
+ doScroll = true;
+ scrollAmount = scrollByDelta;
+ if (deltaMode == event.DOM_DELTA_PIXEL) {
+ instant = true;
+ }
+ }
+
+ if (this._prevMouseScrolls.length > 1) {
+ this._prevMouseScrolls.shift();
+ }
+ this._prevMouseScrolls.push(isVertical);
+ }
+
+ if (doScroll) {
+ let direction = scrollAmount < 0 ? -1 : 1;
+
+ if (deltaMode == event.DOM_DELTA_PAGE) {
+ scrollAmount *= this.scrollClientSize;
+ } else if (deltaMode == event.DOM_DELTA_LINE) {
+ // Try to not scroll by more than one page when using line scrolling,
+ // so that all elements are scrollable.
+ let lineAmount = this.lineScrollAmount;
+ let clientSize = this.scrollClientSize;
+ if (Math.abs(scrollAmount * lineAmount) > clientSize) {
+ // NOTE: This still tries to scroll a non-fractional amount of
+ // items per line scrolled.
+ scrollAmount =
+ Math.max(1, Math.floor(clientSize / lineAmount)) * direction;
+ }
+ scrollAmount *= lineAmount;
+ } else {
+ // DOM_DELTA_PIXEL, leave scrollAmount untouched.
+ }
+ let startPos = this.scrollPosition;
+
+ if (!this._isScrolling || this._direction != direction) {
+ this._destination = startPos + scrollAmount;
+ this._direction = direction;
+ } else {
+ // We were already in the process of scrolling in this direction
+ this._destination = this._destination + scrollAmount;
+ scrollAmount = this._destination - startPos;
+ }
+ this.scrollByPixels(scrollAmount, instant);
+ }
+
+ event.stopPropagation();
+ event.preventDefault();
+ }
+
+ on_touchstart(event) {
+ if (event.touches.length > 1) {
+ // Multiple touch points detected, abort. In particular this aborts
+ // the panning gesture when the user puts a second finger down after
+ // already panning with one finger. Aborting at this point prevents
+ // the pan gesture from being resumed until all fingers are lifted
+ // (as opposed to when the user is back down to one finger).
+ this._touchStart = -1;
+ } else {
+ this._touchStart =
+ this.getAttribute("orient") == "vertical"
+ ? event.touches[0].screenY
+ : event.touches[0].screenX;
+ }
+ }
+
+ on_touchmove(event) {
+ if (event.touches.length == 1 && this._touchStart >= 0) {
+ var touchPoint =
+ this.getAttribute("orient") == "vertical"
+ ? event.touches[0].screenY
+ : event.touches[0].screenX;
+ var delta = this._touchStart - touchPoint;
+ if (Math.abs(delta) > 0) {
+ this.scrollByPixels(delta, true);
+ this._touchStart = touchPoint;
+ }
+ event.preventDefault();
+ }
+ }
+
+ on_touchend(event) {
+ this._touchStart = -1;
+ }
+
+ on_underflow(event) {
+ // Ignore underflow events:
+ // - from nested scrollable elements
+ // - corresponding to an overflow event that we ignored
+ if (event.target != this.scrollbox || !this.hasAttribute("overflowing")) {
+ return;
+ }
+
+ // Ignore events that doesn't match our orientation.
+ // Scrollport event orientation:
+ // 0: vertical
+ // 1: horizontal
+ // 2: both
+ if (this.getAttribute("orient") == "vertical") {
+ if (event.detail == 1) {
+ return;
+ }
+ } else if (event.detail == 0) {
+ // horizontal scrollbox
+ return;
+ }
+
+ this.removeAttribute("overflowing");
+ this._updateScrollButtonsDisabledState();
+ }
+
+ on_overflow(event) {
+ // Ignore overflow events:
+ // - from nested scrollable elements
+ if (event.target != this.scrollbox) {
+ return;
+ }
+
+ // Ignore events that doesn't match our orientation.
+ // Scrollport event orientation:
+ // 0: vertical
+ // 1: horizontal
+ // 2: both
+ if (this.getAttribute("orient") == "vertical") {
+ if (event.detail == 1) {
+ return;
+ }
+ } else if (event.detail == 0) {
+ // horizontal scrollbox
+ return;
+ }
+
+ this.setAttribute("overflowing", "true");
+ this._updateScrollButtonsDisabledState();
+ }
+
+ on_scroll(event) {
+ this._isScrolling = true;
+ this._updateScrollButtonsDisabledState();
+ }
+
+ on_scrollend(event) {
+ this._isScrolling = false;
+ this._destination = 0;
+ this._direction = 0;
+ }
+
+ on_click(event) {
+ if (
+ event.originalTarget != this._scrollButtonUp &&
+ event.originalTarget != this._scrollButtonDown
+ ) {
+ return;
+ }
+ this._onButtonClick(event);
+ }
+
+ on_mousedown(event) {
+ if (event.originalTarget == this._scrollButtonUp) {
+ this._onButtonMouseDown(event, -1);
+ }
+ if (event.originalTarget == this._scrollButtonDown) {
+ this._onButtonMouseDown(event, 1);
+ }
+ }
+
+ on_mouseup(event) {
+ if (
+ event.originalTarget != this._scrollButtonUp &&
+ event.originalTarget != this._scrollButtonDown
+ ) {
+ return;
+ }
+ this._onButtonMouseUp(event);
+ }
+
+ on_mouseover(event) {
+ if (event.originalTarget == this._scrollButtonUp) {
+ this._onButtonMouseOver(-1);
+ }
+ if (event.originalTarget == this._scrollButtonDown) {
+ this._onButtonMouseOver(1);
+ }
+ }
+
+ on_mouseout(event) {
+ if (
+ event.originalTarget != this._scrollButtonUp &&
+ event.originalTarget != this._scrollButtonDown
+ ) {
+ return;
+ }
+ this._onButtonMouseOut();
+ }
+ }
+
+ customElements.define("arrowscrollbox", MozArrowScrollbox);
+}