system back-button closes the app

[GoogleCodeExporter]

Steps to reproduce

1. start the app
2. open a random folder
3. tap the system back-button (left lower corner of the screen)

Expected result:
app should list the initial folder

Actual result:
app closes

Original issue reported on code.google.com by imnother...@gmail.com on 21 Sep 2012 at 9:12

[GoogleCodeExporter]

I experienced this, and I thought it was by design. After checking code, I 
noticed there was a preference for this, but when I went back to app to set it, 
found it was already set and that back did navigate up to parent now, but I 
can't reproduce this original issue.

What is the intended functionality be if the setting is not checked? Opening 
the last folder (not necessarily parent) makes most sense to me.

Original comment by timberwo...@gmail.com on 13 Apr 2013 at 5:19