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tabs.onActivated - Mozilla | MDN
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tabs.onActivated
Fires when the active tab in a window changes. Note that the tab's URL may not be set at the time this event fired, but you can listen to tabs.onUpdated events to be notified when a URL is set.
Syntax
js
browser.tabs.onActivated.addListener(listener)
browser.tabs.onActivated.removeListener(listener)
browser.tabs.onActivated.hasListener(listener)
Events have three functions:
addListener(listener)-
Adds a listener to this event.
removeListener(listener)-
Stop listening to this event. The
listenerargument is the listener to remove. hasListener(listener)-
Check whether
listeneris registered for this event. Returnstrueif it is listening,falseotherwise.
addListener syntax
Parameters
listener-
The function called when this event occurs. The function is passed this argument:
activeInfo-
object. ID of the tab that was made active, and ID of its window. See the activeInfo section for more details.
Additional objects
activeInfo
previousTabId-
integer. The ID of the previous activated tab, if that tab is still open. tabId-
integer. The ID of the tab that has become active. windowId-
integer. The ID of the tab's window.
Examples
Listen for and log tab activation events:
js
function handleActivated(activeInfo) {
console.log(`Tab ${activeInfo.tabId} was activated`);
}
browser.tabs.onActivated.addListener(handleActivated);
Example extensions
Browser compatibility
Loading…
Note:
This API is based on Chromium's chrome.tabs API. This documentation is derived from tabs.json in the Chromium code.