jQuery: How to detect window width on the fly?

Solution 1:

Changing a variable doesn't magically execute code within the if-block. Place the common code in a function, then bind the event, and call the function:

$(document).ready(function() {
    // Optimalisation: Store the references outside the event handler:
    var $window = $(window);
    var $pane = $('#pane1');

    function checkWidth() {
        var windowsize = $window.width();
        if (windowsize > 440) {
            //if the window is greater than 440px wide then turn on jScrollPane..
            $pane.jScrollPane({
               scrollbarWidth:15, 
               scrollbarMargin:52
            });
        }
    }
    // Execute on load
    checkWidth();
    // Bind event listener
    $(window).resize(checkWidth);
});

Solution 2:

Put your if condition inside resize function:

var windowsize = $(window).width();

$(window).resize(function() {
  windowsize = $(window).width();
  if (windowsize > 440) {
    //if the window is greater than 440px wide then turn on jScrollPane..
      $('#pane1').jScrollPane({
         scrollbarWidth:15, 
         scrollbarMargin:52
      });
  }
});

Solution 3:

Below is what i did to hide some Id element when screen size is below 768px, and show up when is above 768px. It works great.

var screensize= $( window ).width();

if(screensize<=768){
        if($('#column-d0f6e77c699556473e4ff2967e9c0251').length>0)
            {
                $('#column-d0f6e77c699556473e4ff2967e9c0251').css('display','none');
            }
}
else{
        if($('#column-d0f6e77c699556473e4ff2967e9c0251').length>0)
            {
                $('#column-d0f6e77c699556473e4ff2967e9c0251').removeAttr( "style" );
            }

}
changething = function(screensize){
        if(screensize<=768){
            if($('#column-d0f6e77c699556473e4ff2967e9c0251').length>0)
            {
                $('#column-d0f6e77c699556473e4ff2967e9c0251').css('display','none');
            }
        }
        else{
        if($('#column-d0f6e77c699556473e4ff2967e9c0251').length>0)
            {
                $('#column-d0f6e77c699556473e4ff2967e9c0251').removeAttr( "style" );
            }

        }
}
$( window ).resize(function() {
 var screensize= $( window ).width();
  changething(screensize);
});