3 files changed, 14 insertions, 1 deletions
diff --git a/src/plugins/platforms/cocoa/qcocoaaccessibility.mm b/src/plugins/platforms/cocoa/qcocoaaccessibility.mm
index 69ec52afe7..c5e40a4087 100644
--- a/src/plugins/platforms/cocoa/qcocoaaccessibility.mm
+++ b/src/plugins/platforms/cocoa/qcocoaaccessibility.mm
@@ -136,6 +136,7 @@ static void populateRoleMap()
     roleMap[QAccessible::Note] = NSAccessibilityGroupRole;
     roleMap[QAccessible::ComplementaryContent] = NSAccessibilityGroupRole;
     roleMap[QAccessible::Graphic] = NSAccessibilityImageRole;
+    roleMap[QAccessible::Tree] = NSAccessibilityOutlineRole;
 }
 
 /*
diff --git a/src/plugins/platforms/cocoa/qcocoaaccessibilityelement.mm b/src/plugins/platforms/cocoa/qcocoaaccessibilityelement.mm
index d63c0401fd..27fd32f91f 100644
--- a/src/plugins/platforms/cocoa/qcocoaaccessibilityelement.mm
+++ b/src/plugins/platforms/cocoa/qcocoaaccessibilityelement.mm
@@ -292,7 +292,9 @@ static void convertLineOffset(QAccessibleTextInterface *text, int *line, int *of
         QAccessibleTableInterface *table = iface->tableInterface();
         Q_ASSERT(table);
         QAccessibleInterface *cell = table->cellAt(m_rowIndex, m_columnIndex);
-        Q_ASSERT(cell && cell->isValid());
+        if (!cell)
+            return nullptr;
+        Q_ASSERT(cell->isValid());
         iface = cell;
 
         // no longer a placeholder
diff --git a/src/widgets/itemviews/qtreeview.cpp b/src/widgets/itemviews/qtreeview.cpp
index 2280cdaa2e..d4c5d837a8 100644
--- a/src/widgets/itemviews/qtreeview.cpp
+++ b/src/widgets/itemviews/qtreeview.cpp
@@ -3325,6 +3325,16 @@ void QTreeViewPrivate::layout(int i, bool recursiveExpanding, bool afterIsUninit
         return;
     }
 
+    // QAccessibleTree's rowCount implementation uses viewItems.size(), so
+    // we need to invalidate any cached accessibility data structures if
+    // that value changes during the run of this function.
+    const auto resetModelIfNeeded = qScopeGuard([oldViewItemsSize = viewItems.size(), this, q]{
+        if (oldViewItemsSize != viewItems.size() && QAccessible::isActive()) {
+            QAccessibleTableModelChangeEvent event(q, QAccessibleTableModelChangeEvent::ModelReset);
+            QAccessible::updateAccessibility(&event);
+        }
+    });
+
     int count = 0;
     if (model->hasChildren(parent)) {
         if (model->canFetchMore(parent)) {