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This API is available on Firefox OS for internal applications only.


The onsettingchange property lets you set an event handler to be called for all setting changes.


SettingsManager.onsettingchange = funcRef;

Where funcRef is a function to be called when a setting state change. This function will receive as input a MozSettingsEvent describing the setting that changed.


// Listen to changes on any settings
navigator.mozSettings.onsettingchange = function (event) {
  console.log(event.settingName + ": " + event.settingValue);


Not part of any specification yet; however, this API will be discussed at W3C as part of the System Applications Working Group.

See also

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 Contributors to this page: chrisdavidmills, teoli, abhishekp, kscarfone, Sheppy, Jeremie
 Last updated by: chrisdavidmills,