I have seen several solutions which determine when an element is visible in the viewport whilst scrolling the page, but I haven't seen any which do this for elements that are contained in a scrolling container div
as in the example here.
How would I detect the items as they scroll into view via the scrolling div? And by contrast how would I detect them if they fell out of view. In all cases the overflow elements are not hidden at the outset.
HTML
<div id="mainContainer" class="main">
<div id="scrollContainer"class="scroller">
<div id="picturesContainer"class="holder">
<div id="pictureContainer1" class="picture position1">
pictureContainer1</div>
<div id="pictureContainer2" class="picture position2">
pictureContainer2</div>
<div id="pictureContainer3" class="picture position3">
pictureContainer3</div>
<div id="pictureContainer4" class="picture position4">
pictureContainer4</div>
<div id="pictureContainer5" class="picture position5">
pictureContainer5</div>
<div id="pictureContainer6" class="picture position6">
pictureContainer6</div>
<div id="pictureContainer7" class="picture position7">
pictureContainer7</div>
<div id="pictureContainer8" class="picture position8">
pictureContainer8</div>
<div id="pictureContainer9" class="picture position9">
pictureContainer9</div>
</div>
</div>
</div>
CSS
.main{
position:absolute;
top:0px;
left:0px;
height: 200px;
width:200px;
background-color: grey;
border: 1px solid black;
}
.scroller{
position:absolute;
top:0px;
left:0px;
height: 250px;
width:250px;
background-color: lightblue;
border: 1px solid black;
overflow: scroll;
}
.picture{
position:absolute;
height: 200px;
width: 200px;
background-color: lightyellow;
border: 1px solid black;
}
.position1{
top:0px;
left:0px;
}
.position2{
top:0px;
left:200px;
}
.position3{
top:0px;
left:400px;
}
.position4{
top:200px;
left:0px;
}
.position5{
top:200px;
left:200px;
}
.position6{
top:200px;
left:400px;
}
.position7{
top:400px;
left:0px;
}
.position8{
top:400px;
left:200px;
}
.position9{
top:400px;
left:400px;
}
.holder{
position:absolute;
top:0px;
left:0px;
width:600px;
height:600px;
background-color:lightgreen;
}
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