opera.contexts.menu.length

This functionality has not landed in a stable Opera version yet, but you can use it already in Opera Next.

Description

This attribute contains the number of items held by the MenuContext.

Note: This is the menu length for the extension only and doesn't include the browser's other existing menu items.

Example:

This example gets the context menu length to confirm that an item was successfully created and added to the menu.

<!-- 
  The configuration file ('config.xml').
-->
<?xml version='1.0' encoding='utf-8'?>
<widget xmlns="http://www.w3.org/ns/widgets">
    ...
    <feature name="opera:contextmenus"/>
    ...
</widget>

//
// The background process (e.g. index.html)
//

if (opera.contexts.menu) {
  var menu = opera.contexts.menu;
  
  // Create a menu item properties object
  var itemProps = {
    title: 'Context Menu Example'
  }

  // Create a menu item with the specified properties
  var item = menu.createItem(itemProps);
  // Add the menu item to the context menu
  menu.addItem(item);
  
  // Check the length of the menu
  if (menu.length > 0) {
    console.log('Menu item successfully created and added.');
  }
}