MIDIAccess: statechange event

Secure context: This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.

The statechange event of the MIDIAccess interface is fired when a new MIDI port is added or when an existing port changes state.

Syntax

Use the event name in methods like addEventListener(), or set an event handler property.

addEventListener('statechange', event => { });

onstatechange = event => { };

Event type

Event properties

MIDIConnectionEvent.portRead only

Returns a reference to a MIDIPort instance for a port that has been connected or disconnected.

Example

The Navigator.requestMIDIAccess() method returns a promise that resolves with a MIDIAccess object. When a port changes state, information about that port is printed to the console.

navigator.requestMIDIAccess()
  .then(function(access) {
     access.onstatechange = event => {
       console.log(event.port.name, event.port.manufacturer, event.port.state);
     };
  });

Specifications

Specification
Web MIDI API
# dom-midiaccess-onstatechange

Browser compatibility

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