我想要我的"回到顶部"当用户在网页显示后不立即向下滚动网页的一半时显示按钮。你怎么能用HTML和CSS做到这一点?
元素我希望大约一半出现,然后点击返回顶部:
<a href="#topPage"><img id="upArrow" src="Images/arrow-up.png" alt="Up arrow"></a>
答案 0 :(得分:0)
让我知道这是否有效:
编辑:添加动画以将用户返回到顶部.click
<script>
$(window).scroll(function () {
if ($(window).scrollTop() > $('body').height() / 2) {
$('#upArrow').fadeTo(500, 1);
}
});
$('#upArrow').click(function(){
$("html, body").animate({ scrollTop: 0 }, "slow");
});
</script>
将upArrow设置为:
<img id="upArrow" style="opacity: 0;" src="Images/arrow-up.png" alt="Up arrow"/>
替代.js:
$(document).ready(function(){
$(window).on('scroll', function() {
var y_scroll_pos = window.pageYOffset;
var scroll_pos_test = 500 // Edit this number to define how far down the page the div fades in.
if(y_scroll_pos > scroll_pos_test) {
$('#upArrow').fadeTo(500, 1);
}
});
});
$('#upArrow').on("click",function(){
$("html, body").animate({ scrollTop: 0 }, "slow");
});