tabs.onZoomChange

Fired when a tab is zoomed.

Syntax

browser.tabs.onZoomChange.addListener(listener)
browser.tabs.onZoomChange.removeListener(listener)
browser.tabs.onZoomChange.hasListener(listener)

Events have three functions:

addListener(callback)
Adds a listener to this event.
removeListener(listener)
Stop listening to this event. The listener argument is the listener to remove.
hasListener(listener)
Check whether listener is registered for this event. Returns true if it is listening, false otherwise.

addListener syntax

Parameters

callback

Function that will be called when this event occurs. The function will be passed the following arguments:

ZoomChangeInfo
object. Information about the zoom event.

Additional objects

ZoomChangeInfo

tabId
integer. ID of the tab that was zoomed.
oldZoomFactor
number. The previous zoom factor.
newZoomFactor
number. The new zoom factor.
zoomSettings
tabs.ZoomSettings. Zoom settings for the tab.

Browser compatibility

Chrome Edge Firefox Firefox for Android Opera
Basic support Yes No 45.0 No 33

Examples

Listen for zoom events and log the info:

function handleZoomed(zoomChangeInfo) {
  console.log("Tab: " + zoomChangeInfo.tabId + " zoomed");
  console.log("Old zoom: " + zoomChangeInfo.oldZoomFactor);
  console.log("New zoom: " + zoomChangeInfo.newZoomFactor);
}

browser.tabs.onZoomChange.addListener(handleZoomed);

Acknowledgements

This API is based on Chromium's chrome.tabs API. This documentation is derived from tabs.json in the Chromium code.

Microsoft Edge compatibility data is supplied by Microsoft Corporation and is included here under the Creative Commons Attribution 3.0 United States License.

Document Tags and Contributors

 Contributors to this page: wbamberg, Makyen
 Last updated by: wbamberg,