WebMIDI | Simple Web MIDI API in and out for some Livid Controllers | Audio Utils library

WebMidi.enable is an asynchronous function, meaning it allows you to specify what to do once WebMidi is enabled. The problem is that you're not using this functionality to full power.

Imagine you're the guy who shoots the gun to start a race: your code is the equivalent of shooting and turning your eyes away from the race but still wanting to know when the race ends. If you want to do something right after the race ends, better look at the race, right?

Right now, the constructor function starts the WebMidi.enable race and immediately tries to fill the dropdown. That's not what you want - you want to fill the dropdown when the race ends.

To resolve your problem, make MidiListener.enable take a callback function that gets executed when WebMidi.enable is done without errors. This will allow you to do something right when WebMidi.enable finishes.

You can use set!.

You have various options: then is just a function, so you can just use (.then ..). If the thenable is a Promise object, promesa https://cljdoc.org/d/funcool/promesa/5.1.0/doc/user-guide has a nice interop story.

It's also pretty simple to add some macro syntax sugar around promises, as I've done here: https://gist.github.com/beders/06eeb1d8f49de715c6bd2b84f634cff6

navigator.requestMIDIAccess() is only available in a secure context, which means your remote host must serve your resources via HTTPS.

Resources served from localhost are considered to be in a secure context, whether delivered via HTTPS or HTTP.

Connect to your remote host using HTTPS instead of HTTP and that should resolve the problem.

It is indeed not yet available. You can follow this issue to get updated of any advancements.

Note that Firefox has a flag to allow the Web Midi API, might worth a try to see if they do handle it.

I've used web-midi with Chromium and Opera on 10.12.6, so I wouldn't say that Chrome is the only browser that has web-midi.

With Opera I think I had to enable experimental features:

The only way to do this I found was to create a virtual midi device as output, and use this virtual midi device as input in my daw. Then use the code above but select the output as this new virtual midi device.

Steps on Mac:
1. Audio Midi Setup -> Window -> Show Midi Studio. 2. In Midi Studio Double Click IAC Driver -> Create New Virtual Midi device with + Button on bottom left corner of screen. Check "Device is Online".

Go to DAW of your choice and change the input to this new midi device. Now in javascript, using the code above, change to the new output:

To use MIDI outputs to play a sound you would need to have a hardware or a software MIDI synthesizer with virtual MIDI ports running. You probably want to use AudioContext instead:

Midi Through Port-0 is a dummy sequencer that doesn't make any sound. I assume you are running on a Linux machine - try the command aconnect -o to see a list of available MIDI outputs, find the device you are trying to play the MIDI notes through and select that one as your output.