1. Mozilla
  2. Add-ons
  3. Browser extensions
  4. JavaScript APIs
  5. devtools
  6. devtools.panels
  7. devtools.panels.ExtensionSidebarPane
  8. devtools.panels.ExtensionSidebarPane.onShown

devtools.panels.ExtensionSidebarPane.onShown

Fired when the sidebar pane becomes visible as a result of the user switching to it.

Syntax

js
browser.devtools.panels.onShown.addListener(listener)
browser.devtools.panels.onShown.removeListener(listener)
browser.devtools.panels.onShown.hasListener(listener)

Events have three functions:

addListener(listener)

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

listener

The function called when this event occurs. The function is passed this argument:

window

object. The window object of the sidebar page, if a page was set with setPage().

Examples

Create a sidebar pane, and log show and hide events.

js
function onCreated(sidebarPane) {
  sidebarPane.onShown.addListener(() => {
    console.log("Shown");
  });

  sidebarPane.onHidden.addListener(() => {
    console.log("Hidden");
  });
}

browser.devtools.panels.elements.createSidebarPane("My pane").then(onCreated);

Browser compatibility

Chrome
Edge
Firefox
Opera
Safari
Firefox for Android
Safari on iOS
onShown
Chrome – Full support
Chrome 18 (Release date: 2012-03-28)
footnote Full support
Edge – Full support
Edge 79 (Release date: 2020-01-15)
footnote Full support
Firefox – Full support
Firefox 57 (Release date: 2017-11-14)
footnote
footnote This event is only fired when the user switches between sidebar panes, not when the user switches between devtools panels. See bug 1412317.
Opera – Full support
Opera 15 (Release date: 2013-07-02)
footnote Full support
Safari – No support
Safari
footnote No support
Firefox for Android – No support
Firefox for Android
footnote No support
Safari on iOS – No support
Safari on iOS
footnote No support

Tip: you can click/tap on a cell for more information.

Full support
No support
See implementation notes.

Note: This API is based on Chromium's chrome.devtools.panels API.

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