Symptoms

 I have created a editable list view. Is there a way to prompt the user that they have changes that have not been saved when they close the form or navigate away from the page?

Diagnoses

As there is not an "Event" that check if the form is closing, there is not a direct way to configure this behavior.

Resolution 

 One possible way to configure a similar behavior is to perhaps commit the changes on item add or item edit on the editable list view rules, such that the editable list view will save the changes if the user ever adds a new row or edit an existing row by adding the "then on view], execute the Save method for all items that have been Changed" or "then on "view], execute the Save method for all items that have been Added".

Of course, this action will only execute if the user clicks away from the item so there will be some scenarios where the changes will not be save (such as if the user add an item, and closes the form without adding a new item or clicking away from it).

To handle these situations, one additional configuration that you can make is to open this editable list as a subview or as a subform that way the "when subform is closing" event or "when subview is closing" event will be available. So that when the user adds/edit a row and closes the subview/subform, you can call an additional "then on osubform] subform, on ]view] view, using ]Smartobject] Smartobject, execute the Save method for all items that have been changed/Add" to handle any situation where there subview/subform is closed.