Replace the volume popup with a more subtle way to display the volume when the user changes it with the volume rocker.

The iOS default popover showing the volume status that appears when the user clicks the volume rocker is a big obtrusive glossy view that covers the content shown. This library offers a way to show a more subtle indicator.
To make sure that the popover is not shown there are two conditions that need to be satisfied:

• An AVAudioSession needs to be active
• An MPVolumeView needs to be in the current view's hierarchy, and its alpha needs to be greater than 0

Once a SubtleVolume is added to your view, an audio session is automatically started, and the view's alpha is set to 0.0001 in the hidden state.

Create an instance of SubtleVolume with one of its convenience initializers, and set its position (you can either set the frame or let autolayout handle it):

let volume = SubtleVolume(style: .plain)
volume.frame = CGRect(x: 0, y: 10, width: UIScreen.main.bounds.width, height: 4) // or wherever you like

Set the barTintColor property:

volume.barTintColor = .red

Set the animation type if needed (no animation will result in the indicator being always visible):

volume.animation = .slideDown

Add the view to your hierarchy:

view.addSubview(volume)

To change the volume programmatically:

try? volume.setVolumeLevel(0.5)

Or use the convenience methods:

try? volume.decreaseVolume(by: 0.2, animated: true)
try? volume.increaseVolume(by: 0.2, animated: true)

Once your app goes in background, you'll need to resume the session when it becomes active:

NotificationCenter.default.addObserver(volume, selector: #selector(SubtleVolume.resume), name: NSNotification.Name.UIApplicationDidBecomeActive, object: nil)

SubtleVolume automatically removes the observer on deinit.

• implement styles
• add test coverage

Copyright (c) 2017-2018 Andrea Mazzini. All rights reserved.

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