// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// 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_ACCESSIBILITY_ACCESSIBILITY_EVENT_ROUTER_VIEWS_H_
#define CHROME_BROWSER_UI_VIEWS_ACCESSIBILITY_ACCESSIBILITY_EVENT_ROUTER_VIEWS_H_
#include <string>
#include "base/basictypes.h"
#include "base/gtest_prod_util.h"
#include "base/strings/string16.h"
#include "chrome/browser/accessibility/accessibility_events.h"
#include "content/public/browser/notification_observer.h"
#include "content/public/browser/notification_registrar.h"
#include "ui/accessibility/ax_enums.h"
class Profile;
template <typename T> struct DefaultSingletonTraits;
namespace views {
class View;
}
// NOTE: This class is part of the Accessibility Extension API, which lets
// extensions receive accessibility events. It's distinct from code that
// implements platform accessibility APIs like MSAA or ATK.
//
// Singleton class that adds listeners to many views, then sends an
// accessibility notification whenever a relevant event occurs in an
// accessible view.
//
// Views are not accessible by default. When you register a root widget,
// that widget and all of its descendants will start sending accessibility
// event notifications. You can then override the default behavior for
// specific descendants using other methods.
//
// You can use Profile::PauseAccessibilityEvents to prevent a flurry
// of accessibility events when a window is being created or initialized.
class AccessibilityEventRouterViews : public content::NotificationObserver {
public:
// Get the single instance of this class.
static AccessibilityEventRouterViews* GetInstance();
// Handle an accessibility event generated by a view.
void HandleAccessibilityEvent(
views::View* view, ui::AXEvent event_type);
// Handle a menu item being focused (separate because a menu item is
// not necessarily its own view).
void HandleMenuItemFocused(const base::string16& menu_name,
const base::string16& menu_item_name,
int item_index,
int item_count,
bool has_submenu);
// NotificationObserver implementation.
virtual void Observe(int type,
const content::NotificationSource& source,
const content::NotificationDetails& details) OVERRIDE;
private:
friend struct DefaultSingletonTraits<AccessibilityEventRouterViews>;
FRIEND_TEST_ALL_PREFIXES(AccessibilityEventRouterViewsTest,
TestFocusNotification);
FRIEND_TEST_ALL_PREFIXES(AccessibilityEventRouterViewsTest,
MenuIndexAndCountForInvisibleMenu);
AccessibilityEventRouterViews();
virtual ~AccessibilityEventRouterViews();
// Call DispatchAccessibilityEvent using a view storage id.
static void DispatchEventOnViewStorageId(
int view_storage_id,
ui::AXEvent event);
// Checks the type of the view and calls one of the more specific
// Send*Notification methods, below.
void DispatchAccessibilityEvent(
views::View* view,
ui::AXEvent event);
// Each of these methods constructs an AccessibilityControlInfo object
// and sends a notification of a specific accessibility event.
static void SendButtonNotification(
views::View* view,
ui::AXEvent event,
Profile* profile);
static void SendLinkNotification(
views::View* view,
ui::AXEvent event,
Profile* profile);
static void SendMenuNotification(
views::View* view,
ui::AXEvent event,
Profile* profile);
static void SendMenuItemNotification(
views::View* view,
ui::AXEvent event,
Profile* profile);
static void SendTreeNotification(
views::View* view,
ui::AXEvent event,
Profile* profile);
static void SendTreeItemNotification(
views::View* view,
ui::AXEvent event,
Profile* profile);
static void SendTextfieldNotification(
views::View* view,
ui::AXEvent event,
Profile* profile);
static void SendComboboxNotification(
views::View* view,
ui::AXEvent event,
Profile* profile);
static void SendCheckboxNotification(
views::View* view,
ui::AXEvent event,
Profile* profile);
static void SendWindowNotification(
views::View* view,
ui::AXEvent event,
Profile* profile);
static void SendSliderNotification(
views::View* view,
ui::AXEvent event,
Profile* profile);
static void SendAlertControlNotification(
views::View* view,
ui::AXEvent event,
Profile* profile);
// Return the name of a view.
static std::string GetViewName(views::View* view);
// Get the context of a view - the name of the enclosing group, toolbar, etc.
static std::string GetViewContext(views::View* view);
// Return a descendant of this view with a given accessible role, if found.
static views::View* FindDescendantWithAccessibleRole(
views::View* view,
ui::AXRole role);
// Recursively explore all menu items of |menu| and return in |count|
// the total number of items, and in |index| the 0-based index of
// |item|, if found. Initialize |count| to zero before calling this
// method. |index| will be unchanged if the item is not found, so
// initialize it to -1 to detect this case.
static void RecursiveGetMenuItemIndexAndCount(views::View* menu,
views::View* item,
int* index,
int* count);
// Recursively explore the subviews and return the text from the first
// subview with a role of STATIC_TEXT.
static std::string RecursiveGetStaticText(views::View* view);
// The profile associated with the most recent window event - used to
// figure out where to route a few events that can't be directly traced
// to a window with a profile (like menu events).
Profile* most_recent_profile_;
// Notification registrar so we can clear most_recent_profile_ when a
// profile is destroyed.
content::NotificationRegistrar registrar_;
DISALLOW_COPY_AND_ASSIGN(AccessibilityEventRouterViews);
};
#endif // CHROME_BROWSER_UI_VIEWS_ACCESSIBILITY_ACCESSIBILITY_EVENT_ROUTER_VIEWS_H_