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author | Zeno Albisser <zeno.albisser@digia.com> | 2013-08-15 21:46:11 +0200 |
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committer | Zeno Albisser <zeno.albisser@digia.com> | 2013-08-15 21:46:11 +0200 |
commit | 679147eead574d186ebf3069647b4c23e8ccace6 (patch) | |
tree | fc247a0ac8ff119f7c8550879ebb6d3dd8d1ff69 /chromium/content/browser/accessibility/browser_accessibility_manager.h | |
download | qtwebengine-chromium-679147eead574d186ebf3069647b4c23e8ccace6.tar.gz |
Initial import.
Diffstat (limited to 'chromium/content/browser/accessibility/browser_accessibility_manager.h')
-rw-r--r-- | chromium/content/browser/accessibility/browser_accessibility_manager.h | 236 |
1 files changed, 236 insertions, 0 deletions
diff --git a/chromium/content/browser/accessibility/browser_accessibility_manager.h b/chromium/content/browser/accessibility/browser_accessibility_manager.h new file mode 100644 index 00000000000..5fac3e5e3f3 --- /dev/null +++ b/chromium/content/browser/accessibility/browser_accessibility_manager.h @@ -0,0 +1,236 @@ +// 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 CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_MANAGER_H_ +#define CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_MANAGER_H_ + +#include <vector> + +#include "base/containers/hash_tables.h" +#include "base/memory/scoped_ptr.h" +#include "build/build_config.h" +#include "content/common/accessibility_node_data.h" +#include "content/common/content_export.h" +#include "ui/gfx/native_widget_types.h" + +struct AccessibilityHostMsg_NotificationParams; + +namespace content { +class BrowserAccessibility; +#if defined(OS_WIN) +class BrowserAccessibilityManagerWin; +#endif + +// Class that can perform actions on behalf of the BrowserAccessibilityManager. +class CONTENT_EXPORT BrowserAccessibilityDelegate { + public: + virtual ~BrowserAccessibilityDelegate() {} + virtual void SetAccessibilityFocus(int acc_obj_id) = 0; + virtual void AccessibilityDoDefaultAction(int acc_obj_id) = 0; + virtual void AccessibilityScrollToMakeVisible( + int acc_obj_id, gfx::Rect subfocus) = 0; + virtual void AccessibilityScrollToPoint( + int acc_obj_id, gfx::Point point) = 0; + virtual void AccessibilitySetTextSelection( + int acc_obj_id, int start_offset, int end_offset) = 0; + virtual bool HasFocus() const = 0; + virtual gfx::Rect GetViewBounds() const = 0; + virtual gfx::Point GetLastTouchEventLocation() const = 0; + virtual void FatalAccessibilityTreeError() = 0; +}; + +class CONTENT_EXPORT BrowserAccessibilityFactory { + public: + virtual ~BrowserAccessibilityFactory() {} + + // Create an instance of BrowserAccessibility and return a new + // reference to it. + virtual BrowserAccessibility* Create(); +}; + +// Manages a tree of BrowserAccessibility objects. +class CONTENT_EXPORT BrowserAccessibilityManager { + public: + // Creates the platform-specific BrowserAccessibilityManager, but + // with no parent window pointer. Only useful for unit tests. + static BrowserAccessibilityManager* Create( + const AccessibilityNodeData& src, + BrowserAccessibilityDelegate* delegate, + BrowserAccessibilityFactory* factory = new BrowserAccessibilityFactory()); + + virtual ~BrowserAccessibilityManager(); + + void Initialize(const AccessibilityNodeData src); + + static AccessibilityNodeData GetEmptyDocument(); + + // Type is enum AccessibilityNotification. + // We pass it as int so that we don't include the message declaration + // header here. + virtual void NotifyAccessibilityEvent( + int type, + BrowserAccessibility* node) { } + + // Return a pointer to the root of the tree, does not make a new reference. + BrowserAccessibility* GetRoot(); + + // Removes a node from the manager. + virtual void RemoveNode(BrowserAccessibility* node); + + // Return a pointer to the object corresponding to the given renderer_id, + // does not make a new reference. + BrowserAccessibility* GetFromRendererID(int32 renderer_id); + + // Called to notify the accessibility manager that its associated native + // view got focused. This implies that it is shown (opposite of WasHidden, + // below). + // The touch_event_context parameter indicates that we were called in the + // context of a touch event. + void GotFocus(bool touch_event_context); + + // Called to notify the accessibility manager that its associated native + // view was hidden. When it's no longer hidden, GotFocus will be called. + void WasHidden(); + + // Called to notify the accessibility manager that a mouse down event + // occurred in the tab. + void GotMouseDown(); + + // Update the focused node to |node|, which may be null. + // If |notify| is true, send a message to the renderer to set focus + // to this node. + void SetFocus(BrowserAccessibility* node, bool notify); + + // Tell the renderer to do the default action for this node. + void DoDefaultAction(const BrowserAccessibility& node); + + // Tell the renderer to scroll to make |node| visible. + // In addition, if it's not possible to make the entire object visible, + // scroll so that the |subfocus| rect is visible at least. The subfocus + // rect is in local coordinates of the object itself. + void ScrollToMakeVisible( + const BrowserAccessibility& node, gfx::Rect subfocus); + + // Tell the renderer to scroll such that |node| is at |point|, + // where |point| is in global coordinates of the WebContents. + void ScrollToPoint( + const BrowserAccessibility& node, gfx::Point point); + + // Tell the renderer to set the text selection on a node. + void SetTextSelection( + const BrowserAccessibility& node, int start_offset, int end_offset); + + // Retrieve the bounds of the parent View in screen coordinates. + gfx::Rect GetViewBounds(); + + // Called when the renderer process has notified us of about tree changes. + // Send a notification to MSAA clients of the change. + void OnAccessibilityNotifications( + const std::vector<AccessibilityHostMsg_NotificationParams>& params); + +#if defined(OS_WIN) + BrowserAccessibilityManagerWin* ToBrowserAccessibilityManagerWin(); +#endif + + // Return the object that has focus, if it's a descandant of the + // given root (inclusive). Does not make a new reference. + BrowserAccessibility* GetFocus(BrowserAccessibility* root); + + // Is the on-screen keyboard allowed to be shown, in response to a + // focus event on a text box? + bool IsOSKAllowed(const gfx::Rect& bounds); + + // True by default, but some platforms want to treat the root + // scroll offsets separately. + virtual bool UseRootScrollOffsetsWhenComputingBounds(); + + // For testing only: update the given nodes as if they were + // received from the renderer process in OnAccessibilityNotifications. + // Takes up to 7 nodes at once so tests don't need to create a vector + // each time. + void UpdateNodesForTesting( + const AccessibilityNodeData& node, + const AccessibilityNodeData& node2 = AccessibilityNodeData(), + const AccessibilityNodeData& node3 = AccessibilityNodeData(), + const AccessibilityNodeData& node4 = AccessibilityNodeData(), + const AccessibilityNodeData& node5 = AccessibilityNodeData(), + const AccessibilityNodeData& node6 = AccessibilityNodeData(), + const AccessibilityNodeData& node7 = AccessibilityNodeData()); + + protected: + BrowserAccessibilityManager( + BrowserAccessibilityDelegate* delegate, + BrowserAccessibilityFactory* factory); + + BrowserAccessibilityManager( + const AccessibilityNodeData& src, + BrowserAccessibilityDelegate* delegate, + BrowserAccessibilityFactory* factory); + + virtual void AddNodeToMap(BrowserAccessibility* node); + + virtual void NotifyRootChanged() {} + + private: + // The following states keep track of whether or not the + // on-screen keyboard is allowed to be shown. + enum OnScreenKeyboardState { + // Never show the on-screen keyboard because this tab is hidden. + OSK_DISALLOWED_BECAUSE_TAB_HIDDEN, + + // This tab was just shown, so don't pop-up the on-screen keyboard if a + // text field gets focus that wasn't the result of an explicit touch. + OSK_DISALLOWED_BECAUSE_TAB_JUST_APPEARED, + + // A touch event has occurred within the window, but focus has not + // explicitly changed. Allow the on-screen keyboard to be shown if the + // touch event was within the bounds of the currently focused object. + // Otherwise we'll just wait to see if focus changes. + OSK_ALLOWED_WITHIN_FOCUSED_OBJECT, + + // Focus has changed within a tab that's already visible. Allow the + // on-screen keyboard to show anytime that a touch event leads to an + // editable text control getting focus. + OSK_ALLOWED + }; + + // Update a set of nodes using data received from the renderer + // process. + bool UpdateNodes(const std::vector<AccessibilityNodeData>& nodes); + + // Update one node from the tree using data received from the renderer + // process. Returns true on success, false on fatal error. + bool UpdateNode(const AccessibilityNodeData& src); + + void SetRoot(BrowserAccessibility* root); + + BrowserAccessibility* CreateNode( + BrowserAccessibility* parent, + int32 renderer_id, + int32 index_in_parent); + + protected: + // The object that can perform actions on our behalf. + BrowserAccessibilityDelegate* delegate_; + + // Factory to create BrowserAccessibility objects (for dependency injection). + scoped_ptr<BrowserAccessibilityFactory> factory_; + + // The root of the tree of accessible objects and the element that + // currently has focus, if any. + BrowserAccessibility* root_; + BrowserAccessibility* focus_; + + // The on-screen keyboard state. + OnScreenKeyboardState osk_state_; + + // A mapping from renderer IDs to BrowserAccessibility objects. + base::hash_map<int32, BrowserAccessibility*> renderer_id_map_; + + DISALLOW_COPY_AND_ASSIGN(BrowserAccessibilityManager); +}; + +} // namespace content + +#endif // CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_MANAGER_H_ |