/* This Source Code Form is subject to the terms of the Mozilla Public * License, v. 2.0. If a copy of the MPL was not distributed with this * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ #include "AccGroupInfo.h" #include "nsAccUtils.h" #include "Role.h" #include "States.h" using namespace mozilla::a11y; AccGroupInfo::AccGroupInfo(Accessible* aItem, role aRole) : mPosInSet(0), mSetSize(0), mParent(nullptr), mItem(aItem), mRole(aRole) { MOZ_COUNT_CTOR(AccGroupInfo); Update(); } void AccGroupInfo::Update() { Accessible* parent = mItem->Parent(); if (!parent) return; int32_t indexInParent = mItem->IndexInParent(); uint32_t siblingCount = parent->ChildCount(); if (indexInParent == -1 || indexInParent >= static_cast<int32_t>(siblingCount)) { NS_ERROR("Wrong index in parent! Tree invalidation problem."); return; } int32_t level = nsAccUtils::GetARIAOrDefaultLevel(mItem); // Compute position in set. mPosInSet = 1; for (int32_t idx = indexInParent - 1; idx >= 0 ; idx--) { Accessible* sibling = parent->GetChildAt(idx); roles::Role siblingRole = sibling->Role(); // If the sibling is separator then the group is ended. if (siblingRole == roles::SEPARATOR) break; // If sibling is not visible and hasn't the same base role. if (BaseRole(siblingRole) != mRole || sibling->State() & states::INVISIBLE) continue; // Check if it's hierarchical flatten structure, i.e. if the sibling // level is lesser than this one then group is ended, if the sibling level // is greater than this one then the group is split by some child elements // (group will be continued). int32_t siblingLevel = nsAccUtils::GetARIAOrDefaultLevel(sibling); if (siblingLevel < level) { mParent = sibling; break; } // Skip subset. if (siblingLevel > level) continue; // If the previous item in the group has calculated group information then // build group information for this item based on found one. if (sibling->mBits.groupInfo) { mPosInSet += sibling->mBits.groupInfo->mPosInSet; mParent = sibling->mBits.groupInfo->mParent; mSetSize = sibling->mBits.groupInfo->mSetSize; return; } mPosInSet++; } // Compute set size. mSetSize = mPosInSet; for (uint32_t idx = indexInParent + 1; idx < siblingCount; idx++) { Accessible* sibling = parent->GetChildAt(idx); roles::Role siblingRole = sibling->Role(); // If the sibling is separator then the group is ended. if (siblingRole == roles::SEPARATOR) break; // If sibling is visible and has the same base role if (BaseRole(siblingRole) != mRole || sibling->State() & states::INVISIBLE) continue; // and check if it's hierarchical flatten structure. int32_t siblingLevel = nsAccUtils::GetARIAOrDefaultLevel(sibling); if (siblingLevel < level) break; // Skip subset. if (siblingLevel > level) continue; // If the next item in the group has calculated group information then // build group information for this item based on found one. if (sibling->mBits.groupInfo) { mParent = sibling->mBits.groupInfo->mParent; mSetSize = sibling->mBits.groupInfo->mSetSize; return; } mSetSize++; } if (mParent) return; roles::Role parentRole = parent->Role(); if (ShouldReportRelations(mRole, parentRole)) mParent = parent; // ARIA tree and list can be arranged by using ARIA groups to organize levels. if (parentRole != roles::GROUPING) return; // Way #1 for ARIA tree (not ARIA treegrid): previous sibling of a group is a // parent. In other words the parent of the tree item will be a group and // the previous tree item of the group is a conceptual parent of the tree // item. if (mRole == roles::OUTLINEITEM) { Accessible* parentPrevSibling = parent->PrevSibling(); if (parentPrevSibling && parentPrevSibling->Role() == mRole) { mParent = parentPrevSibling; return; } } // Way #2 for ARIA list and tree: group is a child of an item. In other words // the parent of the item will be a group and containing item of the group is // a conceptual parent of the item. if (mRole == roles::LISTITEM || mRole == roles::OUTLINEITEM) { Accessible* grandParent = parent->Parent(); if (grandParent && grandParent->Role() == mRole) mParent = grandParent; } } Accessible* AccGroupInfo::FirstItemOf(Accessible* aContainer) { // ARIA tree can be arranged by ARIA groups case #1 (previous sibling of a // group is a parent) or by aria-level. a11y::role containerRole = aContainer->Role(); Accessible* item = aContainer->NextSibling(); if (item) { if (containerRole == roles::OUTLINEITEM && item->Role() == roles::GROUPING) item = item->FirstChild(); if (item) { AccGroupInfo* itemGroupInfo = item->GetGroupInfo(); if (itemGroupInfo && itemGroupInfo->ConceptualParent() == aContainer) return item; } } // ARIA list and tree can be arranged by ARIA groups case #2 (group is // a child of an item). item = aContainer->LastChild(); if (!item) return nullptr; if (item->Role() == roles::GROUPING && (containerRole == roles::LISTITEM || containerRole == roles::OUTLINEITEM)) { item = item->FirstChild(); if (item) { AccGroupInfo* itemGroupInfo = item->GetGroupInfo(); if (itemGroupInfo && itemGroupInfo->ConceptualParent() == aContainer) return item; } } // Otherwise, it can be a direct child if the container is a list or tree. item = aContainer->FirstChild(); if (ShouldReportRelations(item->Role(), containerRole)) return item; return nullptr; } Accessible* AccGroupInfo::NextItemTo(Accessible* aItem) { AccGroupInfo* groupInfo = aItem->GetGroupInfo(); if (!groupInfo) return nullptr; // If the item in middle of the group then search next item in siblings. if (groupInfo->PosInSet() >= groupInfo->SetSize()) return nullptr; Accessible* parent = aItem->Parent(); uint32_t childCount = parent->ChildCount(); for (uint32_t idx = aItem->IndexInParent() + 1; idx < childCount; idx++) { Accessible* nextItem = parent->GetChildAt(idx); AccGroupInfo* nextGroupInfo = nextItem->GetGroupInfo(); if (nextGroupInfo && nextGroupInfo->ConceptualParent() == groupInfo->ConceptualParent()) { return nextItem; } } NS_NOTREACHED("Item in the middle of the group but there's no next item!"); return nullptr; } bool AccGroupInfo::ShouldReportRelations(role aRole, role aParentRole) { // We only want to report hierarchy-based node relations for items in tree or // list form. ARIA level/owns relations are always reported. if (aParentRole == roles::OUTLINE && aRole == roles::OUTLINEITEM) return true; if (aParentRole == roles::TREE_TABLE && aRole == roles::ROW) return true; if (aParentRole == roles::LIST && aRole == roles::LISTITEM) return true; return false; }