The CreateMIDIAccess interface of the Web MIDI API provides methods for listing MIDI input and output devices, and obtaining access to those devices.
You can an instance of the music object when you need it like this:
midi = music.CreateMIDIAccess()
Example
function OnStart()
{
var music = app.CreateMusic()
var midi = music.CreateMIDIAccess()
midi.SetOnAccess(devices => app.Alert("Finded " + devices.length + " device"), "Access")
midi.SetOnMessage(msg => app.Alert("input: " + msg.data.input + ", value: " + msg.data.value, "Message"))
midi.SetOnError((err, code) => app.Alert(err, "Error"))
midi.RequestAccess()
}
Methods:
Is access available, list devices and access object
Listen if MIDI send message.
Catch MIDI errors.
midi.RequestAccess()
Start operations.