/** * Processes the touch-action css property for an Ext.dom.Element, and provides * compatible behavior on devices that do not support pointer events. * @private */Ext.define('Ext.dom.TouchAction', { singleton: true, requires: [ 'Ext.dom.Element', 'Ext.util.Point' ], lastTouchStartTime: 0, /** * @property * The minimum distance a touch must move before being cancelled (only applicable * on browsers that use touch events). Allows the direction of movement to be detected * so that panX and panY can be separately cancelled. * @private */ minMoveDistance: 8, spaceRe: /\s+/, preventSingle: null, preventMulti: null, disabledOverflowDom: null, panXCls: Ext.baseCSSPrefix + 'touch-action-pan-x', panYCls: Ext.baseCSSPrefix + 'touch-action-pan-y', cssValues: [ 'none', 'pan-x', 'pan-y', 'pan-x pan-y', 'pinch-zoom', 'pan-x pinch-zoom', 'pan-y pinch-zoom', 'pan-x pan-y pinch-zoom', 'double-tap-zoom', 'pan-x double-tap-zoom', 'pan-y double-tap-zoom', 'pan-x pan-y double-tap-zoom', 'pinch-zoom double-tap-zoom', 'pan-x pinch-zoom double-tap-zoom', 'pan-y pinch-zoom double-tap-zoom', '' ], objectValues: [ { panX: false, panY: false, pinchZoom: false, doubleTapZoom: false }, { panX: true, panY: false, pinchZoom: false, doubleTapZoom: false }, { panX: false, panY: true, pinchZoom: false, doubleTapZoom: false }, { panX: true, panY: true, pinchZoom: false, doubleTapZoom: false }, { panX: false, panY: false, pinchZoom: true, doubleTapZoom: false }, { panX: true, panY: false, pinchZoom: true, doubleTapZoom: false }, { panX: false, panY: true, pinchZoom: true, doubleTapZoom: false }, { panX: true, panY: true, pinchZoom: true, doubleTapZoom: false }, { panX: false, panY: false, pinchZoom: false, doubleTapZoom: true }, { panX: true, panY: false, pinchZoom: false, doubleTapZoom: true }, { panX: false, panY: true, pinchZoom: false, doubleTapZoom: true }, { panX: true, panY: true, pinchZoom: false, doubleTapZoom: true }, { panX: false, panY: false, pinchZoom: true, doubleTapZoom: true }, { panX: true, panY: false, pinchZoom: true, doubleTapZoom: true }, { panX: false, panY: true, pinchZoom: true, doubleTapZoom: true }, { panX: true, panY: true, pinchZoom: true, doubleTapZoom: true } ], attributeName: 'data-extTouchAction', constructor: function() { var me = this, supports = Ext.supports; if (supports.TouchAction) { me.cssProp = 'touch-action'; } else if (supports.MSPointerEvents) { me.cssProp = '-ms-touch-action'; } if (supports.TouchEvents) { Ext.getWin().on({ touchstart: 'onTouchStart', touchmove: 'onTouchMove', touchend: 'onTouchEnd', scope: me, translate: false, capture: true, priority: 5000 }); Ext.on({ scroll: 'onScroll', scope: me, destroyable: true }); } //<debug> if (Ext.isFunction(Object.freeze)) { var objectValues = me.objectValues; for (var i = 0, ln = objectValues.length; i < ln; i++) { Object.freeze(objectValues[i]); } } //</debug> }, /** * Returns true if all of the event's targets are contained within the element * @param {HTMLElement} dom * @param {Ext.event.Event} e * @private * @return {Boolean} */ containsTargets: function(dom, e) { var contains = true, touches = e.type === 'touchend' ? e.changedTouches : e.touches, i, ln; for (i = 0, ln = touches.length; i < ln; i++) { if (!dom.contains(touches[i].target)) { contains = false; break; } } return contains; }, /** * Forces overflow to 'hidden' on the x or y axis starting with the "el" and ascending * upward to all ancestors that have overflow 'auto' or 'scroll' on the given axis. * The added classes will remain in place until the end of the current gesture (when * the final touchend event is received) at which point they will be removed by invoking * {@link #resetOverflow}. * * This is invoked at the beginning of a gesture when we make the initial determination * that we are disabling scrolling on one of the axes (because touch-action contains * pan-x or pan-y in the value, but not both). Dynamically manipulating the overflow * in this way vs just adding a static class ensures that the non-touch-scrolling axis * can still be scrolled using the mouse. * * We only do this on browsers that do not have space-consuming scrollbars (e.g. on * android, but not on chrome desktop) to avoid a situation where scrollbars disappear * during the gesture and re-appear afterwards. * * We also skip this on iOS because of the following bugs in safari (already filed with apple): * 1. Dynamically setting scroll position to hidden on either axis resets visual scroll * position to 0: * https://gist.github.com/pguerrant/105e8d91e3ffcb1b6e2eed7ecc0571d3 * 2. Scrolling an element that has overflow set to hidden on either axis causes scroll * position to be reset to 0 on the hidden axis: * https://gist.github.com/pguerrant/e959c47a6b1d4b841cc3267a61950f33 * * The downside is that on iOS, and on desktop-touch hybrid browsers such as chrome once * the user initiates scrolling in an allowed direction, it cannot be disabled in the * disallowed direction, This trade-off seems better than the alternatives - * vanishing/reappearing scrollbars on desktop, and scroll positions resetting to 0 on iOS. * * @param {HTMLElement} dom * @param {Boolean} [vertical=false] `true` to disable scrolling on the y axis, `false` * to disable scrolling on the x axis * * @private */ disableOverflow: function(dom, vertical) { var me = this, overflowName = vertical ? 'overflow-y' : 'overflow-x', overflowStyle, cls; if (!me.disabledOverflowDom && !Ext.isiOS && !Ext.getScrollbarSize().width) { me.disabledOverflowDom = dom; cls = vertical ? me.panXCls : me.panYCls; while (dom) { overflowStyle = Ext.fly(dom).getStyle(overflowName); if (overflowStyle === 'auto' || overflowStyle === 'scroll') { Ext.fly(dom).addCls(cls); } dom = dom.parentNode; } } }, /** * Returns the touch action for the passed HTMLElement * @param {HTMLElement} dom * @return {Object} */ get: function(dom) { var flags = dom.getAttribute(this.attributeName), ret = null; if (flags != null) { ret = this.objectValues[flags]; } return ret; }, /** * Accepts a touch action in the object form accepted by * {@link Ext.Component}, and converts it to a number representing the desired touch action(s). * * All touchActions absent from the passed object are defaulted to true. * * @param {Object} touchAction * @returns {Number} A number representing the touch action using the following mapping: * * panX 1 "00000001" * panY 2 "00000010" * pinchZoom 4 "00000100" * doubleTapZoom 8 "00001000" * * 0 represents a css value of "none" and all bits on is the same as "auto" * @private */ getFlags: function(touchAction) { var flags; if (typeof touchAction === 'number') { flags = touchAction; } else { flags = 0; if (touchAction.panX !== false) { flags |= 1; } if (touchAction.panY !== false) { flags |= 2; } if (touchAction.pinchZoom !== false) { flags |= 4; } if (touchAction.doubleTapZoom !== false) { flags |= 8; } } return flags; }, isScrollable: function(el, vertical, forward) { var overflowStyle = Ext.fly(el).getStyle(vertical ? 'overflow-y': 'overflow-x'), isScrollable = (overflowStyle === 'auto' || overflowStyle === 'scroll'); if (isScrollable) { if (vertical) { isScrollable = forward ? (el.scrollTop + el.clientHeight) < el.scrollHeight : el.scrollTop > 0; } else { isScrollable = forward ? (el.scrollLeft + el.clientWidth) < el.scrollWidth : el.scrollLeft > 0; } } return isScrollable; }, lookupFlags: function(dom) { return parseInt((dom.getAttribute && dom.getAttribute(this.attributeName)) || 15, 10); }, onScroll: function() { // This flag tracks whether or not a scroll has occurred since the last touchstart event this.scrollOccurred = true; // once scrolling begins we cannot attempt to preventDefault on the touchend event // or chrome will issue warnings in the console. this.isDoubleTap = false; }, onTouchEnd: function(e) { var me = this, dom = e.target, touchCount, flags, doubleTapZoom; touchCount = e.touches.length; if (touchCount === 0) { if (me.isDoubleTap) { while (dom) { flags = me.lookupFlags(dom); if (flags != null) { doubleTapZoom = flags & 8; if (!doubleTapZoom) { e.preventDefault(); } } dom = dom.parentNode; } } me.isDoubleTap = false; me.preventSingle = null; me.preventMulti = null; me.resetOverflow(); } }, onTouchMove: function(e) { var me = this, prevent = null, dom = e.target, flags, touchCount, panX, panY, point, startPoint, isVertical, scale, distance, deltaX, deltaY, preventSingle, preventMulti; preventSingle = me.preventSingle; preventMulti = me.preventMulti; touchCount = e.touches.length; // Don't check for touchCount here when checking for preventMulti. // This ensures that if we determined not to cancel the multi-touch gesture // previously we will not attempt to start canceling once touch count is // reduced to one (If we do attempt to start canceling at that point chrome // will issue warnings in the console because scrolling has already started). if ((touchCount === 1 && (preventSingle === false)) || (preventMulti === false)) { return; } if ((touchCount > 1 && (preventMulti === true)) || (touchCount === 1 && (preventSingle === true))) { prevent = true; } else { if (touchCount === 1) { point = e.getPoint(); startPoint = me.startPoint; scale = Ext.Element.getViewportScale(); // account for scale so that move distance is actual screen pixels, not page pixels distance = point.getDistanceTo(me.startPoint) * scale; deltaX = point.x - startPoint.x; deltaY = point.y - startPoint.y; isVertical = Math.abs(deltaY) >= Math.abs(deltaX); } while (dom && (dom.nodeType === 1)) { flags = me.lookupFlags(dom); if (flags & 0) { // touch-action: none prevent = true; } else if (touchCount === 1) { panX = !!(flags & 1); panY = !!(flags & 2); if (panX && panY) { prevent = false; } else if (!panX && !panY) { prevent = true; } else if (distance >= me.minMoveDistance) { prevent = !!((panX && isVertical) || (panY && !isVertical)); } // if the element itself is scrollable, and has no touch action // preventing it from scrolling, allow it to scroll - do // not allow an ancestor's touchAction to prevent scrolling if (!prevent && me.isScrollable(dom, isVertical, (isVertical ? deltaY : deltaX) < 0)) { break; } } else if (me.containsTargets(dom, e)) { // multi-touch, all targets contained prevent = !(flags & 4); } else { // multi-touch and not all targets contained within element prevent = false; } if (prevent) { break; } dom = dom.parentNode; } } // In chrome preventing a touchmove event does not prevent the defualt // action such as scrolling from taking place on subsequent touchmove // events. Setting these flags tells us to prevent the touchmove event // for the remainder of the gesture. // explicitly setting these flags to false means do not prevent this gesture // going forward. This prevents chrome from complaining because we // called preventDefault() after scrolling has already started if (touchCount === 1) { me.preventSingle = prevent; } else if (touchCount > 1) { me.preventMulti = prevent; } if (prevent) { e.preventDefault(); } }, onTouchStart: function(e) { var me = this, time, flags, dom, panX, panY; if (e.touches.length === 1) { time = e.time; // Use a time of 500ms between touchstart events to detecting a double tap that // might possibly cause the screen to zoom. Although in reality this is usually // 300ms iOS can sometimes take a bit longer so 500 seems safe. // Can't be a double tap if a scroll occurred in between this touch and the previous // one. if (!me.scrollOccurred && ((time - me.lastTouchStartTime) <= 500)) { me.isDoubleTap = true; } me.lastTouchStartTime = time; me.scrollOccurred = false; me.startPoint = e.getPoint(); dom = e.target; while (dom) { flags = me.lookupFlags(dom); if (flags != null) { panX = !!(flags & 1); panY = !!(flags & 2); if (panX !== panY) { me.disableOverflow(dom, panX); break; } } dom = dom.parentNode; } } else { // multi touch is never a double tap me.isDoubleTap = false; } }, /** * Removes any classes that were added using {@link #disableOverflow} */ resetOverflow: function() { var me = this, dom = me.disabledOverflowDom; while (dom) { Ext.fly(dom).removeCls([me.panXCls, me.panYCls]); dom = dom.parentNode; } me.disabledOverflowDom = null; }, /** * Sets the touch action value for an element * @param {HTMLElement} dom The dom element * @param {Object/Number} value The touch action as an object with touch action names * as keys and boolean values, or as a bit flag (see {@link #getFlags}) * * For example the following two calls are equivalent: * * Ext.dom.TouchAction.set(domElement, { * panX: false, * pinchZoom: false * }); * * Ext.dom.TouchAction.set(domElement, 5); * * valid touch action names are: * * - `'panX'` * - `'panY'` * - `'pinchZoom'` * - `'doubleTapZoom'` * * @private */ set: function(dom, value) { var me = this, cssProp = me.cssProp, flags = me.getFlags(value), // We can only set values for CSS touch-action in the dom if they are supported // by the browser, otherwise the entire touch-action property is ignored. supportedFlags = (flags & Ext.supports.TouchAction), attributeName = me.attributeName; if (cssProp) { Ext.fly(dom).setStyle(cssProp, me.cssValues[supportedFlags]); } if (flags === 15) { dom.removeAttribute(attributeName); } else { dom.setAttribute(attributeName, flags); } }});