在手机浏览器中，先window.scroll滚动到一定的位置,再用手滑动页面，页面会回顶部，从顶部跟随手指移动
if(!!sessionStorage.getItem("scrollTop")){
window.scrollBy(0,sessionStorage.getItem("scrollTop"));
}
childBox.addEventListener('touchstart', function (e) {
lastY = startY = e.touches[0].clientY; //觸摸點相對瀏覽器的位置
//console.log("currY" + currY)
//起始時間和位置
lastMoveStart = lastY;
lastMoveTime = Date.now();
stopInertiaMove = true;
});
childBox.addEventListener('touchmove', function (e) {
e.preventDefault(); //防止打開連接
moveY = e.touches[0].clientY;
distanceY = moveY - startY;
Com.removeTransition();
if (distanceY <= 0) {
Com.setTranslateY(currY + distanceY);
//超過30時，顯示滑動信息
if ((currY + distanceY) >= maxSwipe - 30) {
LeXinIntance.find(".LexinSlideDown").show();
} else if ((currY + distanceY) <= minSwipe + 30) {
LeXinIntance.find(".LexinSlideUp").show();
}
if (!IsPc) {
var pare_h = LeXinIntance.height();
var wrap_h = $("body").height() - 50;
var CanScrollHeight = wrap_h - pare_h;
//matrix(1, 0, 0, 1, 0, -11) //獲取已經異動的高度
scrollTop = document.documentElement.scrollTop || window.pageYOffset || document.body.scrollTop;
//console.log("scrollTop" + scrollTop + "," + CanScrollHeight);
if (Number(scrollTop) >= (Math.abs(CanScrollHeight) - 30)) {
//LeXinIntance.find(".LexinSlideUp>span:nth-of-type(2)").text("laoding next page")
LeXinIntance.find(".LexinSlideUp").show();
} else if (scrollTop > 10) {
LeXinIntance.find(".LexinSlideDown").show();
//LeXinIntance.find(".LexinSlideDown>span:nth-of-type(2)").text("laoding prepage")
} else {
//LeXinIntance.find(".LexinSlideDown>span:nth-of-type(2)").text("Click or slide down Load prepage");
//LeXinIntance.find(".LexinSlideUp>span:nth-of-type(2)").text("Click or slide up Load next page");
}
}
}
ismove = true;
/**
* 缓动代码
*/
var nowTime = Date.now(); //滑動當前時間
stopInertiaMove = true; //表示滑動過
//滑動時間超過0.3秒重置起始時間和位置
if (nowTime - lastMoveTime > 300) {
lastMoveTime = nowTime;
lastMoveStart = moveY;
}
});
childBox.addEventListener('touchend', function (e) {
//console.log("ismove" + ismove)
if (ismove) {
/*记录当前的定位 上一次当前的定位 + 这一次改变的定位*/
currY = currY + distanceY;
if (!IsPc) {
var pare_h = LeXinIntance.height();
var wrap_h = $("body").height() - 50;
var CanScrollHeight = wrap_h - pare_h;
scrollTop = document.documentElement.scrollTop || window.pageYOffset || document.body.scrollTop;
if (Number(scrollTop) >= (Math.abs(CanScrollHeight) - 30)) {
LeXinIntance.find(".LexinSlideUp").hide();
//LeXinIntance.find(".LexinSlideUp>span:nth-of-type(2)").text("Click or slide up Load next page");
//var comLi = LeXinIntance.find(".on").find("*").length;
SliderupLoad();
//if (comLi == LeXinIntance.find(".on").find("*").length) {
// LeXinIntance.find(".LexinSlideUp>span:nth-of-type(2)").text("is bottom");
}
else {
//慣性滾動
var nowY = e.changedTouches[0].clientY;
var nowTime = Date.now();
var v = (nowY - lastMoveStart) / (nowTime - lastMoveTime); //最后一段时间手指划动速度
stopInertiaMove = false; //停止滑動
(function (v, startTime) {
var dir = v > 0 ? -1 : 1; //加速度方向 向下滑動v>0加速度dir<0,向上滑v<0加速度dir>0
var deceleration = dir * 0.002; //每次速度減少量
var duration = v / deceleration; // 速度消减至0所需时间
var dist = v * duration / 2; //最终移动多少 0~V的平均速度 移動duration長時間的距離
//console.log("v" + v);
//console.log("inertiaMove" + dir + "," + deceleration + "," + duration + "," + dist + "," + currY + "," + startTime);
Com.removeTransition(); //取消動畫效果,採用setTimeout取代
function inertiaMove() {
if (stopInertiaMove)
return;
var nT = Date.now();
var t = nT - startTime;
var nowV = v + t * deceleration;
// 速度方向变化表示速度达到0了
if (v * nowV <= 0) {
return;
}
var mY = (v + nowV) / 2 * t;
//console.log("t" + t + "," + currY + "," + CanScrollHeight + "," +v + "," + nowV + "," +mY);
//console.log("mY" + mY);
if (currY <= 0) {
if (currY + mY > 0 && dir == -1) {
//已到頂
//console.log("已到頂");
currY = 0;
Com.setTranslateY(currY);
return;
} else if (currY + mY < CanScrollHeight && dir == 1) {
//已到底 -200<-135
//console.log("已到底" + CanScrollHeight);
currY = CanScrollHeight;
//Com.addTransition();
Com.setTranslateY(CanScrollHeight);
return;
} else {
currY = currY + mY;
Com.setTranslateY(currY);
setTimeout(inertiaMove, 10);
}
}
}
inertiaMove();
})(v, nowTime);
}
}
/*重置所有的参数 不重置currY */
startY = 0;
moveY = 0;
distanceY = 0;
ismove = false;
}
});
setTranslateY: function (y) {
window.scrollTo(0, Math.abs(y));
}
