我正在使用Skrollr菜单使用以下
按下按钮上的页面HTML
<a href="#End"><div class="trigger-scroll left">></div></a>
... the page i want to reveal, using scrolling ...
<section id="End" class="scroll-here">
<div class="hsContainer bottom"></div>
</section>
的JavaScript
var s = skrollr.init();
skrollr.menu.init(s, {
animate: true,
//How long the animation should take in ms.
duration: function(currentTop, targetTop) {
//By default, the duration is hardcoded at 500ms.
return 18000;
//But you could calculate a value based on the current scroll position (`currentTop`) and the target scroll position (`targetTop`).
//return Math.abs(currentTop - targetTop) * 10;
},
//This event is triggered right before we jump/animate to a new hash.
change: function(newHash, newTopPosition) {
//Do stuff
},
//Add hash link (e.g. `#foo`) to URL or not.
updateUrl: false //defaults to `true`.
});
当我点击按钮时会发生什么，它可以正常工作，这不是问题。
问题在于它似乎改变了速度，因为skrollr-menu为页面设置了动画。它开始很快，这意味着页面上的前几个元素（大约是第一个2000px）闪过不可读。然后速度均匀，直到最后3000px（大约），其中skrollr菜单非常慢。我想要的是单击按钮类似于按住键盘或滚动侧边栏上的向下箭头，默认情况下skrollr菜单似乎没有。
我尝试使用数学公式来改变速度，但无论我尝试什么，问题仍然存在，而且似乎没有任何“简单”方式来改变加速度，我怀疑问题出在某处在Skrollr.menu.js文件中，但我看不到哪里。
有什么方法可以使滚动速度均匀，而不是在开始时快速而在结束时减慢？
注意：我在JavaScript或jQuery方面不是很有经验，所以它可能是我忽略的一些简单。
github上的skrollr菜单 https://github.com/Prinzhorn/skrollr-menu
Skrollr.menu.js
/*!
* Plugin for skrollr.
* This plugin makes hashlinks scroll nicely to their target position.
*
* Alexander Prinzhorn - https://github.com/Prinzhorn/skrollr
*
* Free to use under terms of MIT license
*/
(function(document, window) {
'use strict';
var DEFAULT_DURATION = 500;
var DEFAULT_EASING = 'sqrt';
var DEFAULT_SCALE = 1;
var MENU_TOP_ATTR = 'data-menu-top';
var MENU_OFFSET_ATTR = 'data-menu-offset';
var MENU_DURATION_ATTR = 'data-menu-duration';
var MENU_IGNORE_ATTR = 'data-menu-ignore';
var skrollr = window.skrollr;
var history = window.history;
var supportsHistory = !!history.pushState;
/*
Since we are using event bubbling, the element that has been clicked
might not acutally be the link but a child.
*/
var findParentLink = function(element) {
//We reached the top, no link found.
if(element === document) {
return false;
}
//Yay, it's a link!
if(element.tagName.toUpperCase() === 'A') {
return element;
}
//Maybe the parent is a link.
return findParentLink(element.parentNode);
};
/*
Handle the click event on the document.
*/
var handleClick = function(e) {
//Only handle left click.
if(e.which !== 1 && e.button !== 0) {
return;
}
var link = findParentLink(e.target);
//The click did not happen inside a link.
if(!link) {
return;
}
if(handleLink(link)) {
e.preventDefault();
}
};
/*
Handles the click on a link. May be called without an actual click event.
When the fake flag is set, the link won't change the url and the position won't be animated.
*/
var handleLink = function(link, fake) {
var hash;
//When complexLinks is enabled, we also accept links which do not just contain a simple hash.
if(_complexLinks) {
//The link points to something completely different.
if(link.hostname !== window.location.hostname) {
return false;
}
//The link does not link to the same page/path.
if(link.pathname !== document.location.pathname) {
return false;
}
hash = link.hash;
} else {
//Don't use the href property (link.href) because it contains the absolute url.
hash = link.getAttribute('href');
}
//Not a hash link.
if(!/^#/.test(hash)) {
return false;
}
//The link has the ignore attribute.
if(!fake && link.getAttribute(MENU_IGNORE_ATTR) !== null) {
return false;
}
//Now get the targetTop to scroll to.
var targetTop;
var menuTop;
//If there's a handleLink function, it overrides the actual anchor offset.
if(_handleLink) {
menuTop = _handleLink(link);
}
//If there's a data-menu-top attribute and no handleLink function, it overrides the actual anchor offset.
else {
menuTop = link.getAttribute(MENU_TOP_ATTR);
}
if(menuTop !== null) {
//Is it a percentage offset?
if(/p$/.test(menuTop)) {
targetTop = (menuTop.slice(0, -1) / 100) * document.documentElement.clientHeight;
} else {
targetTop = +menuTop * _scale;
}
} else {
var scrollTarget = document.getElementById(hash.substr(1));
//Ignore the click if no target is found.
if(!scrollTarget) {
return false;
}
targetTop = _skrollrInstance.relativeToAbsolute(scrollTarget, 'top', 'top');
var menuOffset = scrollTarget.getAttribute(MENU_OFFSET_ATTR);
if(menuOffset !== null) {
targetTop += +menuOffset;
}
}
if(supportsHistory && _updateUrl && !fake) {
history.pushState({top: targetTop}, '', hash);
}
var menuDuration = parseInt(link.getAttribute(MENU_DURATION_ATTR), 10);
var animationDuration = _duration(_skrollrInstance.getScrollTop(), targetTop);
if(!isNaN(menuDuration)) {
animationDuration = menuDuration;
}
//Trigger the change if event if there's a listener.
if(_change) {
_change(hash, targetTop);
}
//Now finally scroll there.
if(_animate && !fake) {
_skrollrInstance.animateTo(targetTop, {
duration: animationDuration,
easing: _easing
});
} else {
defer(function() {
_skrollrInstance.setScrollTop(targetTop);
});
}
return true;
};
var jumpStraightToHash = function() {
if(window.location.hash && document.querySelector) {
var link = document.querySelector('a[href="' + window.location.hash + '"]');
if(!link) {
// No link found on page, so we create one and then activate it
link = document.createElement('a');
link.href = window.location.hash;
}
handleLink(link, true);
}
};
var defer = function(fn) {
window.setTimeout(fn, 1);
};
/*
Global menu function accessible through window.skrollr.menu.init.
*/
skrollr.menu = {};
skrollr.menu.init = function(skrollrInstance, options) {
_skrollrInstance = skrollrInstance;
options = options || {};
_easing = options.easing || DEFAULT_EASING;
_animate = options.animate !== false;
_duration = options.duration || DEFAULT_DURATION;
_handleLink = options.handleLink;
_scale = options.scale || DEFAULT_SCALE;
_complexLinks = options.complexLinks === true;
_change = options.change;
_updateUrl = options.updateUrl !== false;
if(typeof _duration === 'number') {
_duration = (function(duration) {
return function() {
return duration;
};
}(_duration));
}
//Use event bubbling and attach a single listener to the document.
skrollr.addEvent(document, 'click', handleClick);
if(supportsHistory) {
skrollr.addEvent(window, 'popstate', function(e) {
var state = e.state || {};
var top = state.top || 0;
defer(function() {
_skrollrInstance.setScrollTop(top);
});
}, false);
}
jumpStraightToHash();
};
//Expose the handleLink function to be able to programmatically trigger clicks.
skrollr.menu.click = function(link) {
//We're not assigning it directly to `click` because of the second ("private") parameter.
handleLink(link);
};
//Private reference to the initialized skrollr.
var _skrollrInstance;
var _easing;
var _duration;
var _animate;
var _handleLink;
var _scale;
var _complexLinks;
var _change;
var _updateUrl;
//In case the page was opened with a hash, prevent jumping to it.
//http://stackoverflow.com/questions/3659072/jquery-disable-anchor-jump-when-loading-a-page
defer(function() {
if(window.location.hash) {
window.scrollTo(0, 0);
}
});
}(document, window));
答案 0 :(得分：0)
问题在于此处的缓动功能
//Now finally scroll there.
if(_animate && !fake) {
_skrollrInstance.animateTo(targetTop, {
duration: animationDuration,
easing: _easing
});
} else {
defer(function() {
_skrollrInstance.setScrollTop(targetTop);
});
}
return true;
看起来，尽管Skrollr声称缓和的默认值是线性的（没有缓和），但默认值是ACTUALLY设置为sqrt（或者至少在我的情况下）。可以通过在skrollr.menu.init中强制缓和为线性或者修改skrollr.menu.js文件以从函数中删除缓动来解决此问题。这两种解决方案中的第一种解决方案更清晰，后来不会引起问题。
skrollr.menu.init(s, {
duration: function(currentTop, targetTop) {return 20000;},
easing: 'linear'
});