The sound played when a notification is delivered.
- iOS 10.0+
- macOS 10.14+
- watchOS 3.0+
UNNotification object when you want the delivery of your notification to be accompanied by a specific sound. To play the default system sound, create your sound object using the
default method. If you want to play a custom sound, create a new sound object and specify the name of the audio file that you want to play.
For local notifications, assign the sound object to the
sound property of your
UNMutable object. For a remote notification, assign the name of your sound file to the
sound key in the
aps dictionary. You can also use a notification service app extension to add a sound file to a notification shortly before delivery. In your extension, create a
UNNotification object and add it to your notification content in the same way that you would for a local notification.
Audio files must already be on the user’s device before they can be played. If you use a predefined set of sounds for your notifications, include the audio files in your app’s bundle. For all other sounds, place a copy of the audio file in the
Library/Sounds folder of your app’s container directory. The
UNNotification object looks only in those two locations.
Prepare Sound Resources
The system sound facility plays custom alert sounds, so they must be in one of the following audio data formats:
You can package the audio data in an
caf file. Sound files must be less than 30 seconds in length. If the sound file is longer than 30 seconds, the system plays the default sound instead.
You can use the
afconvert command-line tool to convert sounds. For example, to convert the system sound
Submarine to IMA4 audio in a CAF file, use the following command in Terminal: