I want the user to be able to change the system volume with a slider, and I realized the only way to do this is with an MPVolumeView.
But I can't find any example code for it, and every method I try to implement won't show up.
So what is the easiest and correct, working way of implementing a MPVolumeView?
Place it as a generic UIView, then use the inspector to set the class to MPVolumeView (ensuring that you also link the MediaPlayer framework). It'll still be shown as a regular slider in IB, but at runtime, it will be an instance of MPVolumeView and will have the necessary styles and behavior. Note that this may not work as expected in the iOS Simulator, which doesn't permit volume control.