I'm designing an interface for an Android app that would allow the user to control the pitch, tempo, volume, etc. of some music playing in the background.
Here's what I've sketched so far:
I avoided using sliders in an attempt to make the UI less cluttered. However, I still want users to be able to change the values of parameters by sliding horizontally across any of them (in addition to being able to click on a +/- button).
E.g., to increase the Volume, you would place a finger on 34% and slide towards the right.
Is there a way to ensure that the user knows about this 'hidden' affordance? Or has anyone seen something similar implemented on an existing application (iOS or Android)?
+
or-
buttons? Will there be multiple increments? If you want slider style control you can't do that, as it's a conflict of what holding the finger in one place might mean. Fresh users might nonetheless do a long press of control button, and that's your opportunity to reveal the sliding affordance. The only confusing part is that the slider-thumb won't usually be where the user is pressing, and so could be confusing. It would likely have to look different from a normal slider (i.e. a bar with a nub on it).