content/public/browser/browser_accessibility_state.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CONTENT_PUBLIC_BROWSER_BROWSER_ACCESSIBILITY_STATE_H_
   6 #define CONTENT_PUBLIC_BROWSER_BROWSER_ACCESSIBILITY_STATE_H_
   7
   8 #include "base/callback_forward.h"
   9
  10 #include "content/common/content_export.h"
  11
  12 namespace content {
  13
  14 // The BrowserAccessibilityState class is used to determine if the browser
  15 // should be customized for users with assistive technology, such as screen
  16 // readers.
  17 class CONTENT_EXPORT BrowserAccessibilityState {
  18  public:
  19   virtual ~BrowserAccessibilityState() { }
  20
  21   // Returns the singleton instance.
  22   static BrowserAccessibilityState* GetInstance();
  23
  24   // Enables accessibility for all running tabs.
  25   virtual void EnableAccessibility() = 0;
  26
  27   // Disables accessibility for all running tabs.
  28   virtual void DisableAccessibility() = 0;
  29
  30   // Called when screen reader client is detected.
  31   virtual void OnScreenReaderDetected() = 0;
  32
  33   // Returns true if the browser should be customized for accessibility.
  34   virtual bool IsAccessibleBrowser() = 0;
  35
  36   // Add a callback method that will be called once, a small while after the
  37   // browser starts up, when accessibility state histograms are updated.
  38   // Use this to register a method to update additional accessibility
  39   // histograms.
  40   virtual void AddHistogramCallback(base::Closure callback) = 0;
  41
  42   virtual void UpdateHistogramsForTesting() = 0;
  43 };
  44
  45 }  // namespace content
  46
  47 #endif  // CONTENT_PUBLIC_BROWSER_BROWSER_ACCESSIBILITY_STATE_H_