Changing volume from Android GUI (Quick Settings) - without volume buttons? Is there a way to change volume - or rather to show the volume change screen - without using the volume buttons? I would have thought I could find on Quick Settings dropdown, but there seems to be nothing there related to volume; as example:

How to Customize Android’s Quick Settings Dropdown



Is it possible to have a shortcut to the volume sliders "applet" here?
If your device is rooted, then it is very possible to do so using a third party application. 

If you are not rooted and on stock ROM, then it is only possible to do if your manufacturer supports it in their android overlay.

For example in Android 4.4.2 kitkat on the samsung galaxy note 10.1 2014 edition, there was an option to adjust volume without the buttons, but the option was removed in the android 5.1 lollipop update.

HOWEVER, this app creates a widget instead and works in the same way as adjusting from the notification area

Google this:
Slider Widget - Volumes on Google play 

You should find the app in question.

Edit:
Here is another one: http://nexus5.wonderhowto.com/how-to/control-volume-directly-from-notification-tray-lollipop-0159666/

Cheers!