我具有此功能,该功能将类添加到窗口区域中可见的元素中。它在滚动时按预期工作,但我也想在document..dready上运行它。我该怎么做?
JS:
function isScrolledIntoView(elem) {
var docViewTop = $(window).scrollTop();
var docViewBottom = docViewTop + $(window).height();
var elemTop = $(elem).offset().top;
var elemBottom = elemTop + $(elem).height();
return ((elemBottom <= docViewBottom) && (elemTop >= docViewTop));
}
$(document).bind('ready load scroll', function() {
$('.box').each(function() {
if (isScrolledIntoView(this) === true) {
$(this).addClass('in-view')
} else {
$(this).removeClass('in-view');
}
});
});
html:
<div class="box">Hello</div>
<div class="box">Hello</div>
<div class="box">Hello</div>
<div class="box">Hello</div>
<div class="box">Hello</div>
jsfiddle
绑定 scroll
事件和 .trigger(event)
IT在文档就绪处理程序上。
$(document).ready(function() {
$(document).on('scroll', function() {
$('.box').each(function() {
$(this).toggleClass('in-view', isScrolledIntoView(this));
});
}).trigger('scroll');
});
function isScrolledIntoView(elem) {
var docViewTop = $(window).scrollTop();
var docViewBottom = docViewTop + $(window).height();
var elemTop = $(elem).offset().top;
var elemBottom = elemTop + $(elem).height();
return ((elemBottom <= docViewBottom) && (elemTop >= docViewTop));
}
$(document).ready(function() {
$(document).on('scroll', function() {
$('.box').each(function() {
$(this).toggleClass('in-view', isScrolledIntoView(this));
});
}).trigger('scroll');
});
.box {
opacity: 0;
margin: 50px 0;
padding: 50px;
background-color: #901a1e;
-webkit-box-sizing: border-box;
box-sizing: border-box;
}
.box.in-view {
opacity: 1;
color: #fff;
-webkit-transition: all 0.8s;
transition: all 0.8s;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div class="box">Hello</div>
<div class="box">Hello</div>
<div class="box">Hello</div>
<div class="box">Hello</div>
<div class="box">Hello</div>
<div class="box">Hello</div>
<div class="box">Hello</div>
<div class="box">Hello</div>
<div class="box">Hello</div>
<div class="box">Hello</div>
<div class="box">Hello</div>
我已经对代码进行了以下更改,并得到了我相信您想要的效果。
function isScrolledIntoView(elem) {
var docViewTop = $(window).scrollTop();
var docViewBottom = docViewTop + $(window).height();
var elemTop = $(elem).offset().top;
var elemBottom = elemTop + $(elem).height();
return ((elemBottom <= docViewBottom) && (elemTop >= docViewTop));
}
$(document).ready( function() {
$('.box').each(function() {
if (isScrolledIntoView(this) === true) {
$(this).addClass('in-view')
} else {
$(this).removeClass('in-view');
}
});
});
$(document).bind('load scroll', function() {
$('.box').each(function() {
if (isScrolledIntoView(this) === true) {
$(this).addClass('in-view')
} else {
$(this).removeClass('in-view');
}
});
});
.box {
opacity: 0;
margin: 50px 0;
padding: 50px;
background-color: #901a1e;
-webkit-box-sizing: border-box;
box-sizing: border-box;
}
.box.in-view {
opacity: 1;
color: #fff;
-webkit-transition: all 0.8s;
transition: all 0.8s;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div class="box">Hello</div>
<div class="box">Hello</div>
<div class="box">Hello</div>
<div class="box">Hello</div>
<div class="box">Hello</div>
<div class="box">Hello</div>
<div class="box">Hello</div>
<div class="box">Hello</div>
<div class="box">Hello</div>
<div class="box">Hello</div>
<div class="box">Hello</div>