BrowserTab.id

By Opera Software

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Description:

The readonly id attribute a unique identifier for this browser tab. The value is a string of characters determined by the implementation and is unique for each browsing session.

Syntax:

readonly DOMString id

Example:

The following example creates a button on the browser toolbar. When the button is clicked, the ID of the currently selected tab is displayed in the button's badge.

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

// Specify the properties of the button before creating it.
var UIItemProperties = {
  disabled: false,
  title: "Example extension",
  icon: "images/icon_18.png",
  badge: {
    backgroundColor: '#cc0000',
    color: '#ffffff'
  }
};

// Create the button and add it to the toolbar.
var button = opera.contexts.toolbar.createItem( UIItemProperties );
opera.contexts.toolbar.addItem(button);

button.addEventListener('click', handleClick, false);

function handleClick() {
  // Get the currently selected tab
  var thisTab = opera.extension.tabs.getSelected();

  // Display the tab's ID in the button's badge
  button.badge.textContent = thisTab.id;
}

This article is licensed under a Creative Commons Attribution 3.0 Unported license.