Sixteen Nine has many features that make it stand out from the crowd. An elegant design, unique layout, Gravatar support in the header and integration of the popular Backstretch jQuery plugin by Scott Robbin are just a few.
After installing the theme, my first reaction was this thing is cool! I love how the background image stretches to fill the background at all widths. My second reaction was wouldn’t it be “cooler” if the background was a slideshow? Turns out slideshow functionality is already built-in to Backstretch and with a couple of simple mods you can implement it on your copy of Sixteen Nine.
Keep in mind these mods remove support for Backstretch via the get_background_image function. With this approach you upload your background images to your WordPress Media Library then add links to those images within the backstretch-set.js file located in the js folder of the Sixteen Nine Theme. You will no longer add the background image via Appearance > Custom Background.
Step 1 – Modify the Enqueue Scripts Function
Click “view raw” in lower right. Modify the sixteen_nine_enqueue_scripts function by removing some of the original code as seen below.
Step 2 – Modify the backstretch-set.js File
Click “view raw” in lower right. Modify the backstretch-set.js file with links to your images as seen below. Note that the last image entry does not end with a comma.
Your background should now be a slideshow based on the images added to your modified backstretch-set.js file. See my copy of Sixteen Nine installed here. You can experiment with the duration and fade settings to achieve the perfect transition between slides.