| // Copyright 2016 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 UI_ACCESSIBILITY_AX_RANGE_H_ |
| #define UI_ACCESSIBILITY_AX_RANGE_H_ |
| |
| #include <memory> |
| #include <utility> |
| #include <vector> |
| |
| #include "base/strings/string16.h" |
| #include "ui/accessibility/ax_tree_manager_map.h" |
| #include "ui/accessibility/platform/ax_platform_node_delegate.h" |
| |
| namespace ui { |
| |
| // A range of ax positions. |
| // |
| // In order to avoid any confusion regarding whether a deep or a shallow copy is |
| // being performed, this class can be moved but not copied. |
| template <class AXPositionType> |
| class AXRange { |
| public: |
| AXRange() |
| : anchor_(AXPositionType::CreateNullPosition()), |
| focus_(AXPositionType::CreateNullPosition()) {} |
| |
| AXRange(std::unique_ptr<AXPositionType> anchor, |
| std::unique_ptr<AXPositionType> focus) { |
| if (anchor) { |
| anchor_ = std::move(anchor); |
| } else { |
| anchor_ = AXPositionType::CreateNullPosition(); |
| } |
| if (focus) { |
| focus_ = std::move(focus); |
| } else { |
| focus = AXPositionType::CreateNullPosition(); |
| } |
| } |
| |
| AXRange(const AXRange& other) = delete; |
| |
| AXRange(AXRange&& other) : AXRange() { |
| anchor_.swap(other.anchor_); |
| focus_.swap(other.focus_); |
| } |
| |
| AXRange& operator=(const AXRange& other) = delete; |
| |
| AXRange& operator=(const AXRange&& other) { |
| if (this != other) { |
| anchor_ = AXPositionType::CreateNullPosition(); |
| focus_ = AXPositionType::CreateNullPosition(); |
| anchor_.swap(other.anchor_); |
| focus_.swap(other.focus_); |
| } |
| return *this; |
| } |
| |
| virtual ~AXRange() {} |
| |
| bool IsNull() const { |
| return !anchor_ || !focus_ || anchor_->IsNullPosition() || |
| focus_->IsNullPosition(); |
| } |
| |
| AXPositionType* anchor() const { |
| DCHECK(anchor_); |
| return anchor_.get(); |
| } |
| |
| AXPositionType* focus() const { |
| DCHECK(focus_); |
| return focus_.get(); |
| } |
| |
| base::string16 GetText() const { |
| base::string16 text; |
| if (IsNull()) |
| return text; |
| |
| std::unique_ptr<AXPositionType> start, end; |
| if (*anchor_ < *focus_) { |
| start = anchor_->AsLeafTextPosition(); |
| end = focus_->AsLeafTextPosition(); |
| } else { |
| start = focus_->AsLeafTextPosition(); |
| end = anchor_->AsLeafTextPosition(); |
| } |
| |
| int start_offset = start->text_offset(); |
| DCHECK_GE(start_offset, 0); |
| int end_offset = end->text_offset(); |
| DCHECK_GE(end_offset, 0); |
| |
| do { |
| text += start->GetInnerText(); |
| start = start->CreateNextTextAnchorPosition(); |
| } while (!start->IsNullPosition() && *start < *end); |
| |
| if (static_cast<size_t>(start_offset) > text.length()) |
| return base::string16(); |
| |
| text = text.substr(start_offset, base::string16::npos); |
| size_t text_length = text.length() - end->GetInnerText().length() + |
| static_cast<size_t>(end_offset); |
| return text.substr(0, text_length); |
| } |
| |
| // Returns a vector of AXRanges that span from the start of an anchor |
| // to the end of an anchor, all of which are in between anchor_ and focus_ |
| // endpoints of this range. |
| std::vector<AXRange<AXPositionType>> GetAnchors() { |
| DCHECK(*anchor_ <= *focus_); |
| |
| std::vector<AXRange<AXPositionType>> anchors; |
| auto range_start = anchor_->Clone(); |
| auto range_end = focus_->Clone(); |
| |
| // Non-null degenerate ranges span no content, but they do have a single |
| // anchor. |
| auto current_anchor_start = range_start->AsLeafTextPosition(); |
| if (!current_anchor_start->IsNullPosition() && *range_start == *range_end) { |
| anchors.emplace_back(AXRange(current_anchor_start->Clone(), |
| current_anchor_start->Clone())); |
| return anchors; |
| } |
| |
| // If start and end are in the same anchor, use end instead of |
| // CreatePositionAtEndOfAnchor to ensure this doesn't return a range that |
| // spans past end. |
| auto current_anchor_end = |
| current_anchor_start->CreatePositionAtEndOfAnchor(); |
| const auto end = range_end->AsLeafTextPosition(); |
| if (*current_anchor_end > *end && |
| end->GetAnchor() == current_anchor_start->GetAnchor()) |
| current_anchor_end = end->Clone(); |
| |
| while (!current_anchor_start->IsNullPosition() && |
| !current_anchor_end->IsNullPosition() && |
| *current_anchor_start < *current_anchor_end) { |
| if (current_anchor_start->GetAnchor() == |
| current_anchor_end->GetAnchor()) { |
| anchors.emplace_back(AXRange(current_anchor_start->Clone(), |
| current_anchor_end->Clone())); |
| } |
| |
| if (*current_anchor_end >= *end) |
| break; |
| |
| if (current_anchor_end->CreateNextTextAnchorPosition() |
| ->IsNullPosition()) { |
| current_anchor_start = current_anchor_start->CreateNextAnchorPosition() |
| ->AsLeafTextPosition(); |
| } else { |
| current_anchor_start = |
| current_anchor_end->CreateNextTextAnchorPosition(); |
| } |
| |
| current_anchor_end = current_anchor_start->CreatePositionAtEndOfAnchor(); |
| |
| // If CreatePositionAtEndOfAnchor goes past the end anchor, use the end |
| // anchor instead. |
| if (*current_anchor_end > *end && |
| end->GetAnchor() == current_anchor_start->GetAnchor()) |
| current_anchor_end = end->Clone(); |
| } |
| |
| return anchors; |
| } |
| |
| // Appends rects in screen coordinates of all text nodes that span between |
| // anchor_ and focus_. Rects outside of the viewport are skipped. |
| std::vector<gfx::Rect> GetScreenRects() const { |
| DCHECK(*anchor_ <= *focus_); |
| std::vector<gfx::Rect> rectangles; |
| auto current_line_start = anchor_->Clone(); |
| auto range_end = focus_->Clone(); |
| |
| while (*current_line_start < *range_end) { |
| auto current_line_end = current_line_start->CreateNextLineEndPosition( |
| ui::AXBoundaryBehavior::CrossBoundary); |
| |
| if (*current_line_end > *range_end) |
| current_line_end = range_end->Clone(); |
| |
| DCHECK(current_line_end->GetAnchor() == current_line_start->GetAnchor()); |
| int length_of_current_line = |
| current_line_end->text_offset() - current_line_start->text_offset(); |
| |
| if (current_line_start->GetAnchor()->data().role == |
| ax::mojom::Role::kInlineTextBox) { |
| current_line_start = current_line_start->CreateParentPosition(); |
| } |
| |
| AXTreeID current_tree_id = current_line_start->tree_id(); |
| AXTreeManager* manager = |
| AXTreeManagerMap::GetInstance().GetManager(current_tree_id); |
| AXNode* current_anchor = current_line_start->GetAnchor(); |
| AXPlatformNodeDelegate* current_anchor_delegate = |
| manager->GetDelegate(current_tree_id, current_anchor->id()); |
| |
| gfx::Rect current_rect = current_anchor_delegate->GetScreenBoundsForRange( |
| current_line_start->text_offset(), length_of_current_line, |
| /*clipped*/ true); |
| |
| // Only add rects that are within the current viewport. The 'clipped' |
| // parameter for GetScreenBoundsForRange will return an empty rect in |
| // that case. |
| if (!current_rect.IsEmpty()) |
| rectangles.emplace_back(current_rect); |
| |
| current_line_start = current_line_end->CreateNextLineStartPosition( |
| ui::AXBoundaryBehavior::CrossBoundary); |
| } |
| |
| return rectangles; |
| } |
| |
| private: |
| std::unique_ptr<AXPositionType> anchor_; |
| std::unique_ptr<AXPositionType> focus_; |
| }; |
| |
| } // namespace ui |
| |
| #endif // UI_ACCESSIBILITY_AX_RANGE_H_ |