// Copyright 2013 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CHROME_BROWSER_UI_VIEWS_TABS_SHARED_TAB_STRIP_OBSERVER_H_
#define CHROME_BROWSER_UI_VIEWS_TABS_SHARED_TAB_STRIP_OBSERVER_H_

#include "chrome/browser/ui/views/chrome_views_export.h"

class TabStrip;

////////////////////////////////////////////////////////////////////////////////
//
// TabStripObserver
//
//  An object implements this interface when it wishes to be notified of changes
//  to the TabStrip.
//
//  Register a TabStripObserver with the TabStrip using its SetTabStripObserver
//  method.
//
////////////////////////////////////////////////////////////////////////////////
class CHROME_VIEWS_EXPORT TabStripObserver {
 public:
  // Sent when a new tab has been added at `index`.
  virtual void OnTabAdded(int index);

  // Sent when the tab at `from_index` has been moved to `to_index`.
  virtual void OnTabMoved(int from_index, int to_index);

  // Sent when the tab at `index` has been removed.
  virtual void OnTabRemoved(int index);

 protected:
  virtual ~TabStripObserver() = default;
};

#endif  // CHROME_BROWSER_UI_VIEWS_TABS_SHARED_TAB_STRIP_OBSERVER_H_