| // Copyright 2014 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_BLINK_AX_TREE_SOURCE_H_ |
| #define CONTENT_RENDERER_ACCESSIBILITY_BLINK_AX_TREE_SOURCE_H_ |
| |
| #include <stdint.h> |
| |
| #include "content/common/ax_content_node_data.h" |
| #include "third_party/WebKit/public/web/WebAXObject.h" |
| #include "third_party/WebKit/public/web/WebDocument.h" |
| #include "ui/accessibility/ax_modes.h" |
| #include "ui/accessibility/ax_node_data.h" |
| #include "ui/accessibility/ax_tree_source.h" |
| |
| namespace content { |
| |
| class BlinkAXTreeSource; |
| class RenderFrameImpl; |
| |
| // Create this on the stack to freeze BlinkAXTreeSource and automatically |
| // un-freeze it when it goes out of scope. |
| class ScopedFreezeBlinkAXTreeSource { |
| public: |
| explicit ScopedFreezeBlinkAXTreeSource(BlinkAXTreeSource* tree_source); |
| ~ScopedFreezeBlinkAXTreeSource(); |
| |
| private: |
| BlinkAXTreeSource* tree_source_; |
| |
| DISALLOW_COPY_AND_ASSIGN(ScopedFreezeBlinkAXTreeSource); |
| }; |
| |
| class BlinkAXTreeSource |
| : public ui::AXTreeSource<blink::WebAXObject, |
| AXContentNodeData, |
| AXContentTreeData> { |
| public: |
| BlinkAXTreeSource(RenderFrameImpl* render_frame, ui::AXMode mode); |
| ~BlinkAXTreeSource() override; |
| |
| // Freeze caches the document, accessibility root, and current focused |
| // object for fast retrieval during a batch of operations. Use |
| // ScopedFreezeBlinkAXTreeSource on the stack rather than calling |
| // these directly. |
| void Freeze(); |
| void Thaw(); |
| |
| // It may be necessary to call SetRoot if you're using a WebScopedAXContext, |
| // because BlinkAXTreeSource can't get the root of the tree from the |
| // WebDocument if accessibility isn't enabled globally. |
| void SetRoot(blink::WebAXObject root); |
| |
| // Walks up the ancestor chain to see if this is a descendant of the root. |
| bool IsInTree(blink::WebAXObject node) const; |
| |
| ui::AXMode accessibility_mode() { return accessibility_mode_; } |
| void SetAccessibilityMode(ui::AXMode new_mode); |
| |
| // Set the id of the node to fetch image data for. Normally the content |
| // of images is not part of the accessibility tree, but one node at a |
| // time can be designated as the image data node, which will send the |
| // contents of the image with each accessibility update until another |
| // node is designated. |
| int image_data_node_id() { return image_data_node_id_; } |
| void set_image_data_node_id(int id) { image_data_node_id_ = id; } |
| |
| void set_max_image_data_size(const gfx::Size& size) { |
| max_image_data_size_ = size; |
| } |
| |
| // Set the id of the node with accessibility focus. The node with |
| // accessibility focus will force loading inline text box children, |
| // which aren't always loaded by default on all platforms. |
| int accessibility_focus_id() { return accessibility_focus_id_; } |
| void set_accessibility_focus_id(int id) { accessibility_focus_id_ = id; } |
| |
| // AXTreeSource implementation. |
| bool GetTreeData(AXContentTreeData* tree_data) const override; |
| blink::WebAXObject GetRoot() const override; |
| blink::WebAXObject GetFromId(int32_t id) const override; |
| int32_t GetId(blink::WebAXObject node) const override; |
| void GetChildren( |
| blink::WebAXObject node, |
| std::vector<blink::WebAXObject>* out_children) const override; |
| blink::WebAXObject GetParent(blink::WebAXObject node) const override; |
| void SerializeNode(blink::WebAXObject node, |
| AXContentNodeData* out_data) const override; |
| bool IsValid(blink::WebAXObject node) const override; |
| bool IsEqual(blink::WebAXObject node1, |
| blink::WebAXObject node2) const override; |
| blink::WebAXObject GetNull() const override; |
| |
| blink::WebDocument GetMainDocument() const; |
| |
| private: |
| const blink::WebDocument& document() const { |
| DCHECK(frozen_); |
| return document_; |
| } |
| const blink::WebAXObject& root() const { |
| DCHECK(frozen_); |
| return root_; |
| } |
| const blink::WebAXObject& focus() const { |
| DCHECK(frozen_); |
| return focus_; |
| } |
| |
| blink::WebAXObject ComputeRoot() const; |
| |
| RenderFrameImpl* render_frame_; |
| |
| ui::AXMode accessibility_mode_; |
| |
| // An explicit root to use, otherwise it's taken from the WebDocument. |
| blink::WebAXObject explicit_root_; |
| |
| // The id of the object with accessibility focus. |
| int accessibility_focus_id_ = -1; |
| |
| // The id of the object to fetch image data for. |
| int image_data_node_id_ = -1; |
| |
| gfx::Size max_image_data_size_; |
| |
| // These are updated when calling |Freeze|. |
| bool frozen_ = false; |
| blink::WebDocument document_; |
| blink::WebAXObject root_; |
| blink::WebAXObject focus_; |
| }; |
| |
| } // namespace content |
| |
| #endif // CONTENT_RENDERER_ACCESSIBILITY_BLINK_AX_TREE_SOURCE_H_ |