// Copyright 2013 The Chromium Authors // 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_ANDROID_H_ #define CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_ANDROID_H_ #include #include #include #include #include #include "base/android/scoped_java_ref.h" #include "content/common/content_export.h" #include "ui/accessibility/accessibility_features.h" #include "ui/accessibility/ax_node.h" #include "ui/accessibility/platform/ax_platform_node.h" #include "ui/accessibility/platform/browser_accessibility.h" namespace content { struct AXStyleData; class CONTENT_EXPORT BrowserAccessibilityAndroid : public ui::BrowserAccessibility { public: static BrowserAccessibilityAndroid* GetFromUniqueId(int32_t unique_id); static void ResetLeafCache(); BrowserAccessibilityAndroid(const BrowserAccessibilityAndroid&) = delete; BrowserAccessibilityAndroid& operator=(const BrowserAccessibilityAndroid&) = delete; ~BrowserAccessibilityAndroid() override; // BrowserAccessibility Overrides. using BrowserAccessibility::GetUniqueId; bool CanFireEvents() const override; void OnDataChanged() override; void OnLocationChanged() override; BrowserAccessibility* PlatformGetLowestPlatformAncestor() const override; std::u16string GetLocalizedStringForImageAnnotationStatus( ax::mojom::ImageAnnotationStatus status) const override; bool IsAndroidTextView() const; bool IsCheckable() const; bool IsChecked() const; bool IsClickable() const override; bool IsCollapsed() const; // Android uses the term "collection" instead of "table". These methods are // pass-through methods to the ax_role_properties IsTableLikeOnAndroid and // IsTableItem. For example, a kList will return true for IsCollection and // false for IsCollectionItem, whereas a kListItem will return the opposite. bool IsCollection() const; bool IsCollectionItem() const; bool IsContentInvalid() const; bool IsDisabledDescendant() const; bool IsEnabled() const; bool IsEditable() const; bool IsExpanded() const; bool IsFocusable() const override; bool IsFormDescendant() const; bool IsHeading() const; bool IsHierarchical() const; bool IsMultiLine() const; bool IsMultiselectable() const; bool IsRangeControlWithoutAriaValueText() const; bool IsReportingCheckable() const; bool IsRequired() const; bool IsScrollable() const; bool IsSeekControl() const; bool IsSelected() const; bool IsSlider() const; bool IsSubscript() const; bool IsSuperscript() const; bool IsTableHeader() const; // This property tells Android if the node can be selected using text offsets. // In Blink, WebAXObject::SetSelection() treats offsets as text offsets only // when the target node is a text object (IsTextObject()) or an atomic text // field (IsAtomicTextField()), otherwise it treats them as child indices. bool IsTextSelectable() const; bool IsVisibleToUser() const; bool ShouldUsePaneTitle() const; const std::string& GetMathTag() const; const std::string& GetMathIntent() const; const std::string& GetMathArg() const; // This returns true for all nodes that we should navigate to. // Nodes that have a generic role, no accessible name, and aren't // focusable or clickable aren't interesting. bool IsInterestingOnAndroid() const; // If it's a heading whose only child is a link, or a heading that is inside // a link, returns the link node if it exists; otherwise nullptr. BrowserAccessibilityAndroid* GetHeadingLinkOrLinkHeading() const; // If this node is interesting (IsInterestingOnAndroid() returns true), // returns |this|. If not, it recursively checks all of the // platform children of this node, and if just a single one is // interesting, returns that one. If no descendants are interesting, or // if more than one is interesting, returns nullptr. const BrowserAccessibilityAndroid* GetSoleInterestingNodeFromSubtree() const; // Returns true if the given subtree has inline text box data, or if there // aren't any to load. bool AreInlineTextBoxesLoaded() const; // Returns a relative score of how likely a node is to be clickable. int ClickableScore() const; int ExpandedState() const; bool CanOpenPopup() const; bool HasAriaCurrent() const; bool HasNonEmptyValue() const; bool HasCharacterLocations() const; bool HasImage() const; bool HasLayoutBasedActions() const; const char* GetClassName() const; bool IsChildOfLeaf() const override; bool IsLeaf() const override; std::u16string GetBrailleLabel() const; std::u16string GetBrailleRoleDescription() const; // Note: In the Android accessibility API, the word "text" is used where other // platforms would use "name". The value returned here will appear in dump // tree tests as "name" in the ...-android.txt files, but as "text" in the // ...-android-external.txt files. On other platforms this may be ::GetName(). std::u16string GetTextContentUTF16() const override; // Returns true if this node or its subtree has text content. // Fast because passing min_length=1 allows GetSubstringTextContentUTF16 to // short-circuit as soon as the first character of text is found, avoiding // full subtree traversal and string allocations. bool HasTextContent() const; std::u16string GetValueForControl() const override; int GetTextContentLengthUTF16() const override; // --- Android Property Mappings --- // These methods map directly to properties in the Android // AccessibilityNodeInfo API. They represent the different "slots" where text // content can be placed. // Returns the text content that should be placed in the Android "text" // property. This is often the "deep" text content from the node and its // subtree. std::u16string GetAndroidText() const; // Returns the text content for the Android "contentDescription" property. std::u16string GetAndroidContentDescription() const; // Returns the text content for the Android "hintText" property. std::u16string GetAndroidHint() const; // Returns the text content for the Android "stateDescription" property. std::u16string GetAndroidStateDescription() const; // Returns the text content for the Android "containerTitle" property. std::u16string GetAndroidContainerTitle() const; // Returns the text content for the Android "supplementalDescription" // property. std::u16string GetAndroidSupplementalDescription() const; // Returns the text content for the Android "paneTitle" property. std::u16string GetAndroidPaneTitle() const; // Returns the text content for the Android "tooltipText" property. std::u16string GetAndroidTooltipText() const; // Returns the localized role description (e.g. "heading level 1"). std::u16string GetAndroidRoleDescription() const; // Returns the error message for invalid content. std::u16string GetAndroidContentInvalidErrorMessage() const; // --- End of Android Property Mappings --- typedef base::RepeatingCallback EarlyExitPredicate; // Gets the text content of this node, up to at least `min_length` if given. // If `style_data` is provided, it's populated with styling information. std::u16string GetSubstringTextContentUTF16( std::optional min_length, AXStyleData* style_data = nullptr) const; static EarlyExitPredicate NonEmptyPredicate(); static EarlyExitPredicate LengthAtLeast(size_t length); std::string GetRoleString() const; std::u16string GetComboboxExpandedText() const; std::u16string GetComboboxExpandedTextFallback() const; std::u16string GetMultiselectableStateDescription() const; std::u16string GetSwitchStateDescription() const; std::u16string GetCheckboxStateDescription() const; std::u16string GetAriaCurrentStateDescription() const; std::u16string GetRadioButtonStateDescription() const; std::string GetCSSDisplay() const; // --- Styling Methods --- float GetTextSize() const; int GetTextStyle() const; int GetTextPosition() const; int GetTextColor() const; int GetTextBackgroundColor() const; std::string GetFontFamily() const; std::optional GetItemIndex() const; std::optional GetItemCount() const; int GetSelectedItemCount() const; int GetSelectionMode() const; // --- Scrolling Methods --- bool CanScrollForward() const; bool CanScrollBackward() const; bool CanScrollUp() const; bool CanScrollDown() const; bool CanScrollLeft() const; bool CanScrollRight() const; int GetScrollX() const; int GetScrollY() const; int GetMinScrollX() const; int GetMinScrollY() const; int GetMaxScrollX() const; int GetMaxScrollY() const; bool Scroll(int direction, bool is_page_scroll) const; int GetChecked() const; int GetTextChangeFromIndex() const; int GetTextChangeAddedCount() const; int GetTextChangeRemovedCount() const; std::u16string GetTextChangeBeforeText() const; // Returns ui::kAXAndroidUndefinedSelectionIndex if no selection. int GetSelectionStart() const; // Returns ui::kAXAndroidUndefinedSelectionIndex if no selection. int GetSelectionEnd() const; int GetEditableTextLength() const; int AndroidInputType() const; int AndroidLiveRegionType() const; int AndroidRangeType() const; std::optional RowCount() const; std::optional ColumnCount() const; std::optional RowIndex() const; std::optional RowSpan() const; std::optional ColumnIndex() const; std::optional ColumnSpan() const; // These are enums from // android.view.accessibility.AccessibilityNodeInfo.CollectionItemInfo in // Java: enum AndroidSortDirection { ANDROID_SORT_DIRECTION_NONE = 0, ANDROID_SORT_DIRECTION_ASCENDING = 1, ANDROID_SORT_DIRECTION_DESCENDING = 2, ANDROID_SORT_DIRECTION_OTHER = 3 }; // This method converts from ax::mojom::IntAttribute::kSortDirection to // android values. If this node is not a table header, it will return // ANDROID_SORT_DIRECTION_NONE as Android only can set the sort direction on // this kind of node. AndroidSortDirection GetSortDirection() const; float RangeMin() const; float RangeMax() const; float RangeCurrentValue() const; // Calls GetLineBoundaries or GetWordBoundaries depending on the value // of |granularity|, or fails if anything else is passed in |granularity|. void GetGranularityBoundaries(int granularity, std::vector* starts, std::vector* ends, int offset); // Enumerates all possible mappings of ax::mojom::StringAttribute::kName to // Android accessibility properties. enum class AndroidNameTo { kUnset = 0, kContainerTitle, kContentDescription, kLabeledBy, kSupplementalDescription, kText, }; // Append line start and end indices for the text of this node // (as returned by GetTextContentUTF16()), adding |offset| to each one. void GetLineBoundaries(std::vector* line_starts, std::vector* line_ends, int offset); // Append word start and end indices for the text of this node // (as returned by GetTextContentUTF16()) to |word_starts| and |word_ends|, // adding |offset| to each one. void GetWordBoundaries(std::vector* word_starts, std::vector* word_ends, int offset); // Return the target of a link or the source of an image. std::u16string GetTargetUrl() const; // On Android, spelling errors are returned as "suggestions". Retreive // all of the suggestions for a given text field as vectors of start // and end offsets. void GetSuggestions(std::vector* suggestion_starts, std::vector* suggestion_ends) const; // Used for tree dumps, generate a string representation of the // AccessibilityNodeInfo object for this node by calling through the // manager to the web_contents_accessibility_android JNI. std::u16string GenerateAccessibilityNodeInfoString() const; // Used to determine paint order to see in what order nodes are drawn. // Used by Android XR. int GetPaintOrder() const; // Returns a list of Android IDs that were set on the node using // aria-labelledby. const std::vector GetLabelledByAndroidIds() const; void EraseLeafCacheDataForNode(); protected: BrowserAccessibilityAndroid(ui::BrowserAccessibilityManager* manager, ui::AXNode* node); std::u16string GetLocalizedString(int message_id) const override; friend class BrowserAccessibility; // Needs access to our constructor. private: static size_t CommonPrefixLength(const std::u16string& a, const std::u16string& b); static size_t CommonSuffixLength(const std::u16string& a, const std::u16string& b); static size_t CommonEndLengths(const std::u16string& a, const std::u16string& b); // Computes whether there is an Android-specific reason that the node is a // leaf. The computed value is cached in GetLeafMap() and is used in the // IsLeaf() computation. bool ComputeIsLeaf() const; bool IsLeafConsideringChildren() const; bool HasFocusableChild() const; bool HasOnlyTextChildren() const; bool HasOnlyTextAndImageChildren() const; bool HasListMarkerChild() const; // Central dispatcher that returns the accessible name if it is mapped to the // given target, otherwise returns an empty string. std::u16string GetAccessibleNameForTarget(AndroidNameTo target) const; // This method determines if a node should promote its value to the "text" // property. When the value is promoted, the accessible name is demoted to // the "hint" property instead. bool ShouldPromoteValueToTextProperty(const std::u16string& value) const; int CountChildrenWithRole(ax::mojom::Role role) const; void AppendTextToString(std::u16string extra_text, std::u16string* string) const; // Returns true if the node has int attribute of kDefaultActionVerb and the // default action verb is kSelect. bool HasSelectActionVerb() const; // Returns tree if any child has kSelect action verb. bool HasSelectActionVerbChildren() const; // Helper function that accumulates the text content for the node by // recursively appending text from its subtree. void AppendSubtreeTextRecursive(std::u16string* accumulated_text, std::optional min_length, AXStyleData* style_data) const; // This method determines if a node should expose its editable value. bool ShouldExposeEditableValue() const; // Computes the name-to-property mapping on Android. AndroidNameTo ComputeAndroidNameTo() const; // Get image description string. std::u16string GetImageAnnotationText() const; // Get canvas description string. std::u16string GetCanvasAnnotationText() const; // Returns true if we should inform the user that this image is unlabeled // (e.g., to invite them to enable image descriptions). bool ShouldInformUserAboutUnlabeledImage( ax::mojom::ImageAnnotationStatus status) const; std::optional GetPopupRoleDescription( ax::mojom::HasPopup has_popup) const; std::u16string old_value_; std::u16string new_value_; // A cached value for the result of `ComputeAndroidNameTo`. mutable std::optional name_to_cache_; }; } // namespace content #endif // CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_ANDROID_H_