The MediaTrackSupportedConstraints
dictionary's volume
property is a read-only Boolean value which is present (and set to true
) in the object returned by MediaDevices.getSupportedConstraints()
if and only if the user agent supports the volume
constraint. If the constraint isn't supported, it's not included in the list, so this value will never be false
.
You can access the supported constraints dictionary by calling navigator.mediaDevices.getSupportedConstraints()
.
Syntax
volumeConstraintSupported = supportedConstraintsDictionary["volume"];
Value
This property is present in the dictionary (and its value is always true
) if the user agent supports the volume
constraint. If the property isn't present, this property is missing from the supported constraints dictionary, and you'll get undefined
if you try to look at its value.
Example
HTML content
<div id="result"> </div>
CSS content
#result { font: 14px "Arial", sans-serif; }
JavaScript content
let result = document.getElementById("result"); if (navigator.mediaDevices.getSupportedConstraints()["volume"]) { result.innerHTML = "Supported!"; } else { result.innerHTML = "Not supported!"; }
Result
Specifications
Specification | Status | Comment |
---|---|---|
Media Capture and Streams The definition of 'volume' in that specification. |
Editor's Draft | Initial specification. |
Browser compatibility
Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari |
---|---|---|---|---|---|
Basic support | (Yes) | 50 (50) | No support | (Yes) | ? |
Feature | Android | Android Webview | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile | Chrome for Android |
---|---|---|---|---|---|---|---|
Basic support | ? | (Yes) | 50.0 (50) | No support | ? | ? | (Yes) |