| // 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_RENDERER_ACCESSIBILITY_RENDERER_ACCESSIBILITY_COMPLETE_H_ |
| #define CONTENT_RENDERER_ACCESSIBILITY_RENDERER_ACCESSIBILITY_COMPLETE_H_ |
| |
| #include <set> |
| #include <vector> |
| |
| #include "base/containers/hash_tables.h" |
| #include "base/memory/weak_ptr.h" |
| #include "content/public/renderer/render_view_observer.h" |
| #include "content/renderer/accessibility/blink_ax_tree_source.h" |
| #include "content/renderer/accessibility/renderer_accessibility.h" |
| #include "third_party/WebKit/public/web/WebAXEnums.h" |
| #include "third_party/WebKit/public/web/WebAXObject.h" |
| #include "ui/accessibility/ax_node_data.h" |
| #include "ui/accessibility/ax_tree_serializer.h" |
| |
| namespace blink { |
| class WebDocument; |
| class WebNode; |
| }; |
| |
| namespace content { |
| class RenderViewImpl; |
| |
| // This is the subclass of RendererAccessibility that implements |
| // complete accessibility support for assistive technology. |
| // |
| // This version turns on Blink's accessibility code and sends |
| // a serialized representation of that tree whenever it changes. It also |
| // handles requests from the browser to perform accessibility actions on |
| // nodes in the tree (e.g., change focus, or click on a button). |
| class CONTENT_EXPORT RendererAccessibilityComplete |
| : public RendererAccessibility { |
| public: |
| explicit RendererAccessibilityComplete(RenderFrameImpl* render_frame); |
| ~RendererAccessibilityComplete() override; |
| |
| // RenderFrameObserver implementation. |
| bool OnMessageReceived(const IPC::Message& message) override; |
| |
| // RendererAccessibility. |
| void HandleWebAccessibilityEvent(const blink::WebAXObject& obj, |
| blink::WebAXEvent event) override; |
| RendererAccessibilityType GetType() override; |
| void FocusedNodeChanged(const blink::WebNode& node) override; |
| virtual void DisableAccessibility() override; |
| |
| void HandleAXEvent(const blink::WebAXObject& obj, ui::AXEvent event); |
| |
| protected: |
| // Send queued events from the renderer to the browser. |
| void SendPendingAccessibilityEvents(); |
| |
| // Check the entire accessibility tree to see if any nodes have |
| // changed location, by comparing their locations to the cached |
| // versions. If any have moved, send an IPC with the new locations. |
| void SendLocationChanges(); |
| |
| private: |
| // Handlers for messages from the browser to the renderer. |
| void OnDoDefaultAction(int acc_obj_id); |
| void OnEventsAck(); |
| void OnChangeScrollPosition(int acc_obj_id, int scroll_x, int scroll_y); |
| void OnScrollToMakeVisible(int acc_obj_id, gfx::Rect subfocus); |
| void OnScrollToPoint(int acc_obj_id, gfx::Point point); |
| void OnSetFocus(int acc_obj_id); |
| void OnSetTextSelection(int acc_obj_id, int start_offset, int end_offset); |
| void OnHitTest(gfx::Point point); |
| void OnReset(int reset_token); |
| void OnFatalError(); |
| |
| // Events from Blink are collected until they are ready to be |
| // sent to the browser. |
| std::vector<AccessibilityHostMsg_EventParams> pending_events_; |
| |
| // The adapter that exposes Blink's accessibility tree to AXTreeSerializer. |
| BlinkAXTreeSource tree_source_; |
| |
| // The serializer that sends accessibility messages to the browser process. |
| ui::AXTreeSerializer<blink::WebAXObject> serializer_; |
| |
| // Current location of every object, so we can detect when it moves. |
| base::hash_map<int, gfx::Rect> locations_; |
| |
| // The most recently observed scroll offset of the root document element. |
| // TODO(dmazzoni): remove once https://bugs.webkit.org/show_bug.cgi?id=73460 |
| // is fixed. |
| gfx::Size last_scroll_offset_; |
| |
| // Set if we are waiting for an accessibility event ack. |
| bool ack_pending_; |
| |
| // Nonzero if the browser requested we reset the accessibility state. |
| // We need to return this token in the next IPC. |
| int reset_token_; |
| |
| // So we can queue up tasks to be executed later. |
| base::WeakPtrFactory<RendererAccessibilityComplete> weak_factory_; |
| |
| DISALLOW_COPY_AND_ASSIGN(RendererAccessibilityComplete); |
| }; |
| |
| #endif // CONTENT_RENDERER_ACCESSIBILITY_RENDERER_ACCESSIBILITY_COMPLETE_H_ |
| |
| } // namespace content |