Make JavaScript change background image every 5 seconds

Question

I am trying to change my background image every 5 seconds. How should I go about this?

window.onload = function () {

  function Timer() {
    window.setInterval         


        

Answer 1

You can make few changes

1.Not sure from where you are calling Timer function (better if have camelCase)

function Timer() {
    window.setInterval("changeImage()", 5000);
  }

Instead you can directly use

setInterval(changeImage, 5000);

changeImage is a callback

2.Could not make out what is this line mean

var bgImg = document.body.style.backgroundImage();

Unsure if can attach a function to style property.

Anyway this below snippet can be useful

window.onload = function () {
     // Array of Images
      var backgroundImg=["https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcRyB57zuc4bms-hDtWMa-4BZvscIlJDm4r7a9WLaO4SAxUvKM-DDA",
                        "https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcQBinSpWOvAtkxjmkf709O3rjH2ObRbWAEn9s0JcWaeL6LMtCbOrQ",
                        "https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcRKY4J2qIFqkuDnABMzeypywbMSZL1cleS8vpySz0KD02wOYORU1g",
                        "https://encrypted-tbn1.gstatic.com/images?q=tbn:ANd9GcRQkdQT0zN0xDVP-VuvwojSbS5dOstX14eZvJCOWNPxKJ5dWTIc"
                        ]

        setInterval(changeImage, 5000);
       function changeImage() {   
        var i = Math.floor((Math.random() * 3));

        document.body.style.backgroundImage = "url('"+backgroundImg[i]+"')";

      }
    }

DEMO