我正在对页面进行编码,以便在滚动时内容淡入淡出。
当你滚动离开"三部曲"部分,然后向上滚动,再次在顶部时不是100%不透明度。
同样内容在三部曲部分的一半淡出,然后再次淡入。当在视图中时,我需要在顶部(减去绿色标题区域)时的内容为100%不透明度。
代码:
$(document).ready(function() {
$(window).bind('scroll', function(e) {
setParalaxContent();
});
function setParalaxContent() {
var trilogy = {
scrollTop: $(window).scrollTop(),
windowHeight: $(window).height(),
contentTop: $('.trilogy2').position().top,
contentHeight:2200
};
// determine scrollTop's bounds where content enters & exits the window
trilogy.lowerBound = trilogy.contentTop - trilogy.windowHeight;
trilogy.upperBound = trilogy.contentTop + trilogy.contentHeight;
// determine scrollTop's position percentage (x2) in relation to bounds
trilogy.percent = (trilogy.scrollTop - trilogy.lowerBound) / (trilogy.upperBound - trilogy.lowerBound) * 2;
}
$('.trilogy2').animate({
opacity: 1 - Math.abs(trilogy.percent - 1)
}, 1);
请参阅以下全部代码: http://jsfiddle.net/warrior_76/pnr4fdyg/