Unable to update header value using hook_views_pre_render?
$view-&gt;display['page']-&gt;handler-&gt;handlers['header']
             ['area_1']-&gt;options['content'] = $my_values;


please change the value of the area_1 if anyone want change the header value programmatically . 

Just hover the Global: Unfiltered text (Global: Unfiltered text) header value and you will get the area_1 value .