With the adoption of PJax on Yii2 things have change quite a bit with GridView when it comes to work with them in AJAX mode. It will probably be confusing at the beginning, but then you will soon realize how powerful the new approach is.
We all know how to upload the content and images at the same time with refreshing the page. And uploading the images using Ajax we have faced some issues, here i have fixed the issues and both content and photos are uploaded using Ajax. And both content and images are stored in the different tables
I am writing this guide because I struggled to find a resource that included ALL of the necessary steps to completely separate the frontend from the backend. After reading guides like Configuring different sessions for backend and frontend in yii-advanced-app and yii2 configuring different sessions for backend and frontend in yii advanced application template, there are still steps missing. It is funny how the 2nd one says it is an extension of the first one's article. So I guess, my wiki guide here is yet a 3rd and more complete extension of both of them. I also found a few StackOverflow questions and blog posts regarding this topic. None of them fully worked, and must be missing some magic sauce!