iOS Rotary Slider Controls – AKA Knobs

We’re now 4 versions into iOS, and Apple still hasn’t brought UISlider up to speed with NSSlider. OS X gets horizontal, vertical, and rotary sliders while iOS is stuck with only horizontal.  There’s probably some UI guideline which states that rotary sliders are no good for touch interfaces but honestly, it is really hard to make an attractive layout with a lot of controls using only horizontal sliders.  Music apps tend to need a lot of controls, and making EQ adjustments using a slider reminds me of the bad old days of generic AudioUnit interfaces.

After a cursory Google search, I couldn’t find any code out there for rotary sliders so I wrote my own UIControl subclass. I tried to stick as closely as possible to the UISlider interface so that it won’t be too hard to switch when Apple gets around to making a standard control. There is a precision property that changes how quickly the knob rotates, this lets you make very accurate adjustments.

XCode Project

Running the marathon – Best App Ever Awards

Thanks to all of your votes, VocaForm is one of ten finalists in two categories in the 2009 Best App Ever Award contest.

The winner in each category will be  selected over the month of January by daily votes from their fans. So go there and help me get the most votes.

Best Musical Instrument: http://bestappever.com/v/miap/325691191

Best Synth App:  http://bestappever.com/v/msap/325691191

I don’t want to spam anyone so if you want to receive a daily reminder follow @VocaForm on Twitter or send an email to timbolstad [at ] gmail.com

Hurt

Nine Inch Nails’ “Hurt” played on my iPhone instrument VocaForm and  acoustic guitar. There is one guitar track, everything else is played on an iPod Touch.

Audio recorded with a PreSonus Firepod and Garageband. Video recorded with a Canon T1i and a Panasonic Lumix DMC-TZ5. Edited in Final Cut Pro.

More info: http://timbolstad.wordpress.com/vocaform
iTunes Link: http://itunes.com/apps/VocaForm