Piano keyboard view for iOS in Swift

PianoKeyboard

An iOS piano keyboard view for iPhone or iPad, written in Swift 5.
Has an IBDesignable preview in interface builder with IBInspectable properties for:

Number of keys
Hide/show note names on white keys
Black key height and width
Hightlight keys, with individual colour (optional play note)
Custom key labels

Other features

Latch/Hold key

All images are drawn using Core Graphics.

Installation

CocoaPods

To use via CocoaPods, add the following line to your Podfile:

pod 'PianoKeyboard'

Swift Package Manager

With Xcode 11+ you can add PianoKeyboard to your project using the Swift Package Manager. From the File menu select Swift Packages and then select Add Package Dependency. A dialogue then will request the package repository URL, enter:

https://github.com/garynewby/PianoKeyboard.git

Demo

The Example app demonstrates how to integrate and use PianoKeyboard in your project. It includes a simple AVAudioEngine/AVAudioUnitSampler based sound source.

Delegate Methods

func pianoKeyDown(_ keyNumber: Int) {
  // Called when the key corresponding to midi number keyNumber is pressed
}

func pianoKeyUp(_ keyNumber: Int) {
  // Called when the key corresponding to midi number keyNumber is released
}

Key Labels

A key's label must be assigned a value for it to show:

keyboard.setLabel(for: 60, text: "Do")
keyboard.setLabel(for: 62, text: "Re")
keyboard.setLabel(for: 64, text: "Mi")

for noteNumber in 65...72 {
    keyboard.setLabel(for: noteNumber, text: Note.name(for: noteNumber))
}