Page was rendered correctly but it display the following error message:
Strict warning: Only variables should be passed by reference in include() (line 31 of C:\xampp\htdocs\mysite\sites\all\themes\mytheme\templates\page.tpl.php).
I have a image field name field_header_image and I want to used the image as the header background image in my page.tpl.php. here is my code
<div id="hero-container" class="hero-container" style="background:linear-gradient(rgba(0, 0, 0, 0.35), rgba(0, 0, 0, 0.35)), url('<?php echo render(file_create_url($node->field_header_image['und']['uri'])); ?>');">
It display correctly and I can use the field image as my header background but it display the above error. Is there a better way to get rid of this error without using a module.