iwmlib/3rdparty/inobounce.min.js

1 line
2.1 KiB
JavaScript

(function(global){var startY=0;var enabled=false;var supportsPassiveOption=false;try{var opts=Object.defineProperty({},"passive",{get:function(){supportsPassiveOption=true}});window.addEventListener("test",null,opts)}catch(e){}var handleTouchmove=function(evt){var el=evt.target;while(el!==document.body&&el!==document){var style=window.getComputedStyle(el);if(!style){break}if(el.nodeName==="INPUT"&&el.getAttribute("type")==="range"){return}var scrolling=style.getPropertyValue("-webkit-overflow-scrolling");var overflowY=style.getPropertyValue("overflow-y");var height=parseInt(style.getPropertyValue("height"),10);var isScrollable=scrolling==="touch"&&(overflowY==="auto"||overflowY==="scroll");var canScroll=el.scrollHeight>el.offsetHeight;if(isScrollable&&canScroll){var curY=evt.touches?evt.touches[0].screenY:evt.screenY;var isAtTop=startY<=curY&&el.scrollTop===0;var isAtBottom=startY>=curY&&el.scrollHeight-el.scrollTop===height;if(isAtTop||isAtBottom){evt.preventDefault()}return}el=el.parentNode}evt.preventDefault()};var handleTouchstart=function(evt){startY=evt.touches?evt.touches[0].screenY:evt.screenY};var enable=function(){window.addEventListener("touchstart",handleTouchstart,supportsPassiveOption?{passive:false}:false);window.addEventListener("touchmove",handleTouchmove,supportsPassiveOption?{passive:false}:false);enabled=true};var disable=function(){window.removeEventListener("touchstart",handleTouchstart,false);window.removeEventListener("touchmove",handleTouchmove,false);enabled=false};var isEnabled=function(){return enabled};var testDiv=document.createElement("div");document.documentElement.appendChild(testDiv);testDiv.style.WebkitOverflowScrolling="touch";var scrollSupport="getComputedStyle"in window&&window.getComputedStyle(testDiv)["-webkit-overflow-scrolling"]==="touch";document.documentElement.removeChild(testDiv);if(scrollSupport){enable()}var iNoBounce={enable:enable,disable:disable,isEnabled:isEnabled};if(typeof module!=="undefined"&&module.exports){module.exports=iNoBounce}if(typeof global.define==="function"){(function(define){define("iNoBounce",[],function(){return iNoBounce})})(global.define)}else{global.iNoBounce=iNoBounce}})(this);