Get width in percentage from Resizable divs from jQuery UI on load and on resize

Question

So I got these two divs next to each other. Both of the divs can already be resized by using the jQuery UI.

On resizing the divs I grab the width make it into a percentage and output it to the corresponding inputs but something strange happens.

The HTML:

<div id="parent">
   <div id="div1"> My Data1
     <input type="text" class="div1">
   </div> 
   <div id="div2"> My Data2
     <input type="text" class="div2">
   </div> 
</div>

The Javascript:

$("#div1").resizable();
$('#div1').resize(function(){
   $('#div2').width($("#parent").width()-$("#div1").width()); 
});
$(window).resize(function(){

   var div1width = $(".div1").width() / $('.div1').parent().width() * 100;
   // Paste percentage into the inputs
   $('.div1').val(div1width);

   var div2width = $(".div2").width() / $('.div2').parent().width() * 100;
   // Paste percentage into the inputs
   $('.div2').val(div2width);
});

The CSS:

#parent{
    position:absolute;
    height:100%;
    margin:0;
    padding:0;
    width:100%;
}
#div1{
    position:relative;
    float:left;
    height:100%;
    width:50%;
    background-color:#A2A;
}
#div2{
    position:relative;
    float:left;
    height:100%;
    width:50%;
    background-color:#BBB;
}
.ui-resizable-e {
    cursor: e-resize;
    width: 7px;
    right: -5px;
    top: 0;
    height: 100%;
    background: black;
}

The fiddle: https://jsfiddle.net/uvcxfmfy/1/

What happens is that when I make for instance div1 smaller the width percentage goes up even all the way over 800%. When I make it wider the width percentage stops at 20%. So something is wrong but I cant find it where.

What I am trying to achieve.

On page load both divs should have 50% width. When I make div1 smaller it should go all the way to 0% when I make it bigger it should go to 100%.

This means that if div1 is set at 25% that div2 will have 75% When div1 is set at 58% then div2 is 42%.

Thanks everyone for helping.

Answer 1

I hope you find it helpful. You should use this math to get percent:

Math.round(( docWidth - elemWidth ) / docWidth * 100)

---

Im just order your code and change the calc line, look at this example :

$("#div1").resizable();

$('#div1').resize(function(){
   $('#div2').width($("#parent").width()-$("#div1").width()); 
});

$(window).resize(function(){
    elementResize()
});

$(document).ready(function(){
    elementResize()
});

function elementResize(){
   $('#div2').width($("#parent").width()-$("#div1").width()); 
   $('#div1').height($("#parent").height()); 

   var parentwidth = $("#parent").width(),
       div1width = $("#div1").width(),
       div2width = $("#div2").width(),
       div1percentage = Math.round((div1width / parentwidth) * 100),
       div2percentage = Math.round((div2width / parentwidth) * 100);

   $('.div1').val(div1percentage);
   $('.div2').val(div2percentage);
}

Fiddle demo