我收到很多报告，在使用此滚动条类时，鼠标滚轮在不同浏览器中的行为会有所不同。在某些浏览器（如Firefox）中，它非常慢，而在其他浏览器中（大多数是Snow Leopard上的Safari版本），它是完美的。
任何想法在这里发生了什么以及如何解决它？我正在使用Mootools库。这里要注意的一行是wheel: (Browser.firefox) ? 20 : 1行。您可以在此处设置鼠标滚轮的速度或步长。
此处设置为jsFiddle：http://jsfiddle.net/brandondurham/6SUyM/
var ScrollBar = new Class({
Implements: [Events, Options],
options: {
wheel: (Browser.firefox) ? 20 : 1
},
initialize: function(main, options) {
this.setOptions(options);
this.main = $(main);
this.content = this.main.getFirst();
this.vScrollbar = new Element('div', {
'class': 'scrollbar'
}).inject(this.content, 'after');
this.vTrack = new Element('div', {
'class': 'track'
}).inject(this.vScrollbar);
this.vThumb = new Element('div', {
'class': 'handle'
}).inject(this.vTrack);
this.bound = {
'vStart': this.vStart.bind(this),
'end': this.end.bind(this),
'vDrag': this.vDrag.bind(this),
'vTouchDrag': this.vTouchDrag.bind(this),
'wheel': this.wheel.bind(this),
'vPage': this.vPage.bind(this),
};
this.vScrollbar.set('tween', {
duration: 200,
transition: 'cubic:out'
});
this.main.addEvent('mouseenter', function(event){
this.vScrollbar.get('tween').cancel();
this.vScrollbar.tween('width', 12);
}.bind(this));
this.main.addEvent('mouseleave', function(event){
this.vScrollbar.get('tween').cancel();
this.vScrollbar.tween('width', 0);
}.bind(this));
this.vPosition = {};
this.vMouse = {};
this.update();
this.attach();
this.scrollContent = new Fx.Scroll(this.content, {
duration: 800,
transition: Fx.Transitions.Cubic.easeOut,
});
this.scrollThumb = new Fx.Morph(this.vThumb, {
duration: 400,
transition: Fx.Transitions.Cubic.easeOut,
});
},
update: function() {
var panel_id = (this.content.getFirst()) ? this.content.getFirst().get('id') : '';
if ((this.content.scrollHeight <= this.main.offsetHeight) || panel_id == 'random-doodle') this.main.addClass('noscroll');
else this.main.removeClass('noscroll');
this.vContentSize = this.content.offsetHeight;
this.vContentScrollSize = this.content.scrollHeight;
this.vTrackSize = this.vTrack.offsetHeight;
this.vContentRatio = this.vContentSize / this.vContentScrollSize;
this.vThumbSize = (this.vTrackSize * this.vContentRatio).limit(12, this.vTrackSize);
this.vScrollRatio = this.vContentScrollSize / this.vTrackSize;
this.vThumb.setStyle('height', this.vThumbSize);
this.vUpdateThumbFromContentScroll();
this.vUpdateContentFromThumbPosition();
},
vUpdateContentFromThumbPosition: function() {
this.content.scrollTop = this.vPosition.now * this.vScrollRatio;
},
vUpdateContentFromThumbPosition2: function() {
var pos = this.vPosition.now * this.vScrollRatio;
this.scrollContent.start(0, pos);
},
vUpdateThumbFromContentScroll: function() {
this.vPosition.now = (this.content.scrollTop / this.vScrollRatio).limit(0, (this.vTrackSize - this.vThumbSize));
this.vThumb.setStyle('top', this.vPosition.now);
},
vUpdateThumbFromContentScroll2: function(pos) {
this.vPosition.now = (this.content.scrollTopNew / this.vScrollRatio).limit(0, (this.vTrackSize - this.vThumbSize));
this.scrollThumb.start({
'top': this.vPosition.now
});
},
attach: function() {
if (this.options.wheel) this.content.addEvent('mousewheel', this.bound.wheel);
this.content.addEvent('touchstart', this.bound.vStart);
this.vThumb.addEvent('mousedown', this.bound.vStart);
this.vTrack.addEvent('mouseup', this.bound.vPage);
},
wheel: function(event) {
this.content.scrollTop -= event.wheel * this.options.wheel;
this.vUpdateThumbFromContentScroll();
event.stop();
},
scrollTo: function(pos){
myInstance = this;
this.content.scrollTopNew = pos;
this.scrollContent.start(0, this.content.scrollTopNew);
myInstance.vUpdateThumbFromContentScroll2(pos);
},
vPage: function(event) {
// if scrolling up
if (event.page.y > this.vThumb.getPosition().y) {
myInstance = this;
this.content.scrollTopNew = this.content.scrollTop.toInt() + this.content.offsetHeight.toInt();
this.scrollContent.start(0, this.content.scrollTopNew);
}
// if scrolling down
else {
myInstance = this;
this.content.scrollTopNew = this.content.scrollTop.toInt() - this.content.offsetHeight.toInt();
this.scrollContent.start(0, this.content.scrollTopNew);
}
myInstance.vUpdateThumbFromContentScroll2(event.page.y);
event.stop();
},
vStart: function(event) {
this.vMouse.start = event.page.y;
this.vPosition.start = this.vThumb.getStyle('top').toInt();
document.addEvent('touchmove', this.bound.vTouchDrag);
document.addEvent('touchend', this.bound.end);
document.addEvent('mousemove', this.bound.vDrag);
document.addEvent('mouseup', this.bound.end);
this.vThumb.addEvent('mouseup', this.bound.end);
event.stop();
},
end: function(event) {
document.removeEvent('touchmove', this.bound.vTouchDrag);
document.removeEvent('mousemove', this.bound.vDrag);
document.removeEvent('mouseup', this.bound.end);
this.vThumb.removeEvent('mouseup', this.bound.end);
event.stop();
},
vTouchDrag: function(event) {
this.vMouse.now = event.page.y;
this.vPosition.now = (this.vPosition.start - (this.vMouse.now - this.vMouse.start)).limit(0, (this.vTrackSize - this.vThumbSize));
this.vUpdateContentFromThumbPosition();
this.vUpdateThumbFromContentScroll();
event.stop();
},
vDrag: function(event) {
this.vMouse.now = event.page.y;
this.vPosition.now = (this.vPosition.start + (this.vMouse.now - this.vMouse.start)).limit(0, (this.vTrackSize - this.vThumbSize));
this.vUpdateContentFromThumbPosition();
this.vUpdateThumbFromContentScroll();
event.stop();
}
});