Delete function and stop it from functioning

Question

I am experimenting with this a library which is called StickySidebar.

It works fine. The only things is, on mobile I don't want this function to be active and do its thing.

This if statement is within a window.resize()

if (window.width() >= desktopSize) {
    var sidebar = new StickySidebar('.side-column', {
        containerSelector: '#maintable',
        innerWrapperSelector: '.sidebar__inner',
        topSpacing: 20,
        bottomSpacing: 20
    });
} else {
    //tried this: var sidebar = undefined;
    //tried this: sidebar.delete();
    //thied this:   var sidebar = new StickySidebar('.side-column', {
                        containerSelector: '.side-column',
                        innerWrapperSelector: '.sidebar__inner',
                        topSpacing: 20,
                        bottomSpacing: 20
                    });
}

So my question is, how do I delete a function from the dom/memory so it wont work anymore?

Answer 1

You need to use the internal methood for destroying stickySidebar.destroy(); which should look like this;

// set up a boolean before running any events

var hasSidebar = false;

// and now execute the below code on every resize event.
window.onresize = function() {

  if ( window.width() >= desktopSize ) {
    if ( !hasSidebar ) {
      // we only want to initialise the sidebar if it's not already
      var sidebar = new StickySidebar('.side-column',  optionsObject );
      hasSidebar = true;

    }
  } else {
    if ( hasSidebar ) { 
      // if sidebar is initialised, we can destroy it safely without error
      sidebar.destroy();
      hasSidebar = false;

    }
  }

}

This will track if the sidebar is initialised or not, because if we do not do this then the program will throw error trying to destroy() a sidebar which doesn't exist.

Answer 2

var sidebar;    
if (window.width() >= desktopSize) {
       sidebar = new StickySidebar('.side-column', {
            containerSelector: '#maintable',
            innerWrapperSelector: '.sidebar__inner',
            topSpacing: 20,
            bottomSpacing: 20
        });
    } else {
        sidebar.destroy();
    }

Sticky sidebar has a destroy method which will destroy it whenever you want. Refer this : https://abouolia.github.io/sticky-sidebar/#usage

Answer 3

Alternate you can detect weather it is a mobile device or not and stop execution of code as per it

var isMobile = false;
// device detection
if(/(android|bb\d+|meego).+mobile|avantgo|bada\/|blackberry|blazer|compal|elaine|fennec|hiptop|iemobile|ip(hone|od)|ipad|iris|kindle|Android|Silk|lge |maemo|midp|mmp|netfront|opera m(ob|in)i|palm( os)?|phone|p(ixi|re)\/|plucker|pocket|psp|series(4|6)0|symbian|treo|up\.(browser|link)|vodafone|wap|windows (ce|phone)|xda|xiino/i.test(navigator.userAgent) 
    || /1207|6310|6590|3gso|4thp|50[1-6]i|770s|802s|a wa|abac|ac(er|oo|s\-)|ai(ko|rn)|al(av|ca|co)|amoi|an(ex|ny|yw)|aptu|ar(ch|go)|as(te|us)|attw|au(di|\-m|r |s )|avan|be(ck|ll|nq)|bi(lb|rd)|bl(ac|az)|br(e|v)w|bumb|bw\-(n|u)|c55\/|capi|ccwa|cdm\-|cell|chtm|cldc|cmd\-|co(mp|nd)|craw|da(it|ll|ng)|dbte|dc\-s|devi|dica|dmob|do(c|p)o|ds(12|\-d)|el(49|ai)|em(l2|ul)|er(ic|k0)|esl8|ez([4-7]0|os|wa|ze)|fetc|fly(\-|_)|g1 u|g560|gene|gf\-5|g\-mo|go(\.w|od)|gr(ad|un)|haie|hcit|hd\-(m|p|t)|hei\-|hi(pt|ta)|hp( i|ip)|hs\-c|ht(c(\-| |_|a|g|p|s|t)|tp)|hu(aw|tc)|i\-(20|go|ma)|i230|iac( |\-|\/)|ibro|idea|ig01|ikom|im1k|inno|ipaq|iris|ja(t|v)a|jbro|jemu|jigs|kddi|keji|kgt( |\/)|klon|kpt |kwc\-|kyo(c|k)|le(no|xi)|lg( g|\/(k|l|u)|50|54|\-[a-w])|libw|lynx|m1\-w|m3ga|m50\/|ma(te|ui|xo)|mc(01|21|ca)|m\-cr|me(rc|ri)|mi(o8|oa|ts)|mmef|mo(01|02|bi|de|do|t(\-| |o|v)|zz)|mt(50|p1|v )|mwbp|mywa|n10[0-2]|n20[2-3]|n30(0|2)|n50(0|2|5)|n7(0(0|1)|10)|ne((c|m)\-|on|tf|wf|wg|wt)|nok(6|i)|nzph|o2im|op(ti|wv)|oran|owg1|p800|pan(a|d|t)|pdxg|pg(13|\-([1-8]|c))|phil|pire|pl(ay|uc)|pn\-2|po(ck|rt|se)|prox|psio|pt\-g|qa\-a|qc(07|12|21|32|60|\-[2-7]|i\-)|qtek|r380|r600|raks|rim9|ro(ve|zo)|s55\/|sa(ge|ma|mm|ms|ny|va)|sc(01|h\-|oo|p\-)|sdk\/|se(c(\-|0|1)|47|mc|nd|ri)|sgh\-|shar|sie(\-|m)|sk\-0|sl(45|id)|sm(al|ar|b3|it|t5)|so(ft|ny)|sp(01|h\-|v\-|v )|sy(01|mb)|t2(18|50)|t6(00|10|18)|ta(gt|lk)|tcl\-|tdg\-|tel(i|m)|tim\-|t\-mo|to(pl|sh)|ts(70|m\-|m3|m5)|tx\-9|up(\.b|g1|si)|utst|v400|v750|veri|vi(rg|te)|vk(40|5[0-3]|\-v)|vm40|voda|vulc|vx(52|53|60|61|70|80|81|83|85|98)|w3c(\-| )|webc|whit|wi(g |nc|nw)|wmlb|wonu|x700|yas\-|your|zeto|zte\-/i.test(navigator.userAgent.substr(0,4))) { 
    isMobile = true;
}
console.log("mobile device detected " + isMobile);

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>

Answer 4

You can set the function's reference to undefined. But be careful, once the function is deleted, you cannot get it back without redeclaring it.

function test() {
	console.log("test");
}

test();

test = undefined;

test(); //Error: test is not a function

Answer 5

You can use $('div').addClass("yourClassName")on some event and $('div').removeClass("yourClassName") if you want to remove on some event. Working in this way can help.