Here is a example on how to use Pjax with GridView (yii\grid\GridView) and ActiveForm (yii\widgets\ActiveForm) widgets in Yii2.
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.
Yii2 comes with a charming twitter bootstrap version 3. But if it is less, then you can integrate with web templates that you like. One example is wonderfull template "adminLTE"
You would find having such a need in most Yii Projects. Your database needs a specific format to store date fields, while you may want to display it in different formats to the users on forms and other views.
There is an issue on Yii2 to redirecting / urls to /frontend/web.
In other words we need a way to hidden /frontend/web from addresses.
We will do this without changing Apache configuration and creating virtual host or setting document root (It's good for share hostings that we have not access to apache.conf)
One of the things you will find tricky to implement is the the sorting and filtering of a GridView's column that displays related model data.
There are a few issues with the other solutions I originally used that I found from other wikis. I address the issues I had in this much simpler and shorter way. I am also going to explain what is going into way more detail than others to help people understand what's going on.