Accessibility: Multiple table fixes

- Fixes an off-by-one error when navigating by rows, caused by treating
  the table header as a row. The table header now has the header
  accessibility role.
- Fixes a bug where reordering table columns would cause the table to
  become inaccessible.
- Fixes a bug where the screen reader would try to navigate hidden table
  columns.
- Fixes an issue where moving the VoiceOver cursor to a partially hidden
  cell would cause the focus to move to the table itself, rather than to
  the cell.

modules/juce_gui_basics/accessibility/interfaces/juce_AccessibilityTableInterface.h

@@ -49,6 +49,21 @@ public:
         nullptr if there is no cell at the specified position.
     */
     virtual const AccessibilityHandler* getCellHandler (int row, int column) const = 0;
+
+    /** Returns the AccessibilityHandler for a row in the table, or nullptr if there is
+        no row at this index.
+
+        The row component should have a child component for each column in the table.
+    */
+    virtual const AccessibilityHandler* getRowHandler (int row) const = 0;
+
+    /** Returns the AccessibilityHandler for the header, or nullptr if there is
+        no header.
+
+        If you supply a header, it must have exactly the same number of children
+        as there are columns in the table.
+    */
+    virtual const AccessibilityHandler* getHeaderHandler() const = 0;
 };
 
 } // namespace juce

modules/juce_gui_basics/native/accessibility/juce_mac_Accessibility.mm

@@ -116,9 +116,7 @@ private:
             addMethod (@selector (accessibilitySelectedRows),        getAccessibilitySelectedRows);
             addMethod (@selector (setAccessibilitySelectedRows:),    setAccessibilitySelectedRows);
             addMethod (@selector (accessibilityColumnCount),         getAccessibilityColumnCount);
-            addMethod (@selector (accessibilityColumns),             getAccessibilityColumns);
+            addMethod (@selector (accessibilityHeader),              getAccessibilityHeader);
-            addMethod (@selector (accessibilitySelectedColumns),     getAccessibilitySelectedColumns);
-            addMethod (@selector (setAccessibilitySelectedColumns:), setAccessibilitySelectedColumns);
 
             addMethod (@selector (accessibilityRowIndexRange),    getAccessibilityRowIndexRange);
             addMethod (@selector (accessibilityColumnIndexRange), getAccessibilityColumnIndexRange);
@@ -166,26 +164,30 @@ private:
             return selected;
         }
 
+        static void setSelected (id item, bool selected)
+        {
+            auto* handler = getHandler (item);
+
+            if (handler == nullptr)
+                return;
+
+            const auto currentState = handler->getCurrentState();
+
+            if (isSelectable (currentState))
+            {
+                if (currentState.isSelected() != selected)
+                    handler->getActions().invoke (AccessibilityActionType::toggle);
+            }
+            else if (currentState.isFocusable())
+            {
+                [item setAccessibilityFocused: selected];
+            }
+        }
+
         static void setSelectedChildren (NSArray* children, NSArray* selected)
         {
             for (id child in children)
-            {
+                setSelected (child, [selected containsObject: child]);
-                if (auto* handler = getHandler (child))
-                {
-                    const auto currentState = handler->getCurrentState();
-                    const BOOL isSelected = [selected containsObject: child];
-
-                    if (isSelectable (currentState))
-                    {
-                        if (currentState.isSelected() != isSelected)
-                            handler->getActions().invoke (AccessibilityActionType::toggle);
-                    }
-                    else if (currentState.isFocusable())
-                    {
-                        [child setAccessibilityFocused: isSelected];
-                    }
-                }
-            }
         }
 
         //==============================================================================
@@ -218,15 +220,15 @@ private:
                         if (auto* modalHandler = modal->getAccessibilityHandler())
                         {
                             if (auto* focusChild = modalHandler->getChildFocus())
-                                return (id) focusChild->getNativeImplementation();
+                                return static_cast<id> (focusChild->getNativeImplementation());
 
-                            return (id) modalHandler->getNativeImplementation();
+                            return static_cast<id> (modalHandler->getNativeImplementation());
                         }
                     }
                 }
 
                 if (auto* focusChild = handler->getChildFocus())
-                    return (id) focusChild->getNativeImplementation();
+                    return static_cast<id> (focusChild->getNativeImplementation());
             }
 
             return nil;
@@ -237,7 +239,7 @@ private:
             if (auto* handler = getHandler (self))
             {
                 if (auto* child = handler->getChildAt (roundToIntPoint (flippedScreenPoint (point))))
-                    return (id) child->getNativeImplementation();
+                    return static_cast<id> (child->getNativeImplementation());
 
                 return self;
             }
@@ -250,9 +252,9 @@ private:
             if (auto* handler = getHandler (self))
             {
                 if (auto* parentHandler = handler->getParent())
-                    return NSAccessibilityUnignoredAncestor ((id) parentHandler->getNativeImplementation());
+                    return NSAccessibilityUnignoredAncestor (static_cast<id> (parentHandler->getNativeImplementation()));
 
-                return NSAccessibilityUnignoredAncestor ((id) handler->getComponent().getWindowHandle());
+                return NSAccessibilityUnignoredAncestor (static_cast<id> (handler->getComponent().getWindowHandle()));
             }
 
             return nil;
@@ -267,7 +269,7 @@ private:
                 auto* accessibleChildren = [NSMutableArray arrayWithCapacity: (NSUInteger) children.size()];
 
                 for (auto* childHandler : children)
-                    [accessibleChildren addObject: (id) childHandler->getNativeImplementation()];
+                    [accessibleChildren addObject: static_cast<id> (childHandler->getNativeImplementation())];
 
                 return accessibleChildren;
             }
@@ -581,27 +583,29 @@ private:
         //==============================================================================
         static NSArray* getAccessibilityRows (id self, SEL)
         {
-            NSMutableArray* rows = [[NSMutableArray new] autorelease];
-
             if (auto* tableInterface = getTableInterface (self))
             {
-                for (int row = 0; row < tableInterface->getNumRows(); ++row)
+                auto* rows = [[NSMutableArray new] autorelease];
+
+                for (int row = 0, numRows = tableInterface->getNumRows(); row < numRows; ++row)
                 {
-                    if (auto* handler = tableInterface->getCellHandler (row, 0))
+                    if (auto* rowHandler = tableInterface->getRowHandler (row))
                     {
-                        [rows addObject: (id) handler->getNativeImplementation()];
+                        [rows addObject: static_cast<id> (rowHandler->getNativeImplementation())];
                     }
                     else
                     {
                         [rows addObject: [NSAccessibilityElement accessibilityElementWithRole: NSAccessibilityRowRole
-                                                                                         frame: NSZeroRect
+                                                                                        frame: NSZeroRect
-                                                                                         label: @"Offscreen Row"
+                                                                                        label: @"Offscreen Row"
-                                                                                        parent: self]];
+                                                                                       parent: self]];
                     }
                 }
+
+                return rows;
             }
 
-            return rows;
+            return nil;
         }
 
         static NSArray* getAccessibilitySelectedRows (id self, SEL)
@@ -614,39 +618,13 @@ private:
             setSelectedChildren ([self accessibilityRows], selected);
         }
 
-        static NSArray* getAccessibilityColumns (id self, SEL)
+        static id getAccessibilityHeader (id self, SEL)
         {
-            NSMutableArray* columns = [[NSMutableArray new] autorelease];
-
             if (auto* tableInterface = getTableInterface (self))
-            {
+                if (auto* handler = tableInterface->getHeaderHandler())
-                for (int column = 0; column < tableInterface->getNumColumns(); ++column)
+                    return static_cast<id> (handler->getNativeImplementation());
-                {
-                    if (auto* handler = tableInterface->getCellHandler (0, column))
-                    {
-                        [columns addObject: (id) handler->getNativeImplementation()];
-                    }
-                    else
-                    {
-                        [columns addObject: [NSAccessibilityElement accessibilityElementWithRole: NSAccessibilityColumnRole
-                                                                                            frame: NSZeroRect
-                                                                                            label: @"Offscreen Column"
-                                                                                           parent: self]];
-                    }
-                }
-            }
 
-            return columns;
+            return nil;
-        }
-
-        static NSArray* getAccessibilitySelectedColumns (id self, SEL)
-        {
-            return getSelectedChildren ([self accessibilityColumns]);
-        }
-
-        static void setAccessibilitySelectedColumns (id self, SEL, NSArray* selected)
-        {
-            setSelectedChildren ([self accessibilityColumns], selected);
         }
 
         //==============================================================================
@@ -743,8 +721,7 @@ private:
                                             @selector (accessibilityRows),
                                             @selector (accessibilitySelectedRows),
                                             @selector (accessibilityColumnCount),
-                                            @selector (accessibilityColumns),
+                                            @selector (accessibilityHeader) })
-                                            @selector (accessibilitySelectedColumns) })
                 {
                     if (selector == tableSelector)
                         return handler->getTableInterface() != nullptr;
@@ -881,7 +858,7 @@ static void sendHandlerNotification (const AccessibilityHandler& handler,
 
     if (@available (macOS 10.9, *))
     {
-        if (id accessibilityElement = (id) handler.getNativeImplementation())
+        if (id accessibilityElement = static_cast<id> (handler.getNativeImplementation()))
         {
             sendAccessibilityEvent (accessibilityElement, notification,
                                     (notification == NSAccessibilityLayoutChangedNotification
@@ -966,7 +943,7 @@ void AccessibilityHandler::postAnnouncement (const String& announcementString, A
             JUCE_END_IGNORE_WARNINGS_GCC_LIKE
         }();
 
-        sendAccessibilityEvent ((id) [NSApp mainWindow],
+        sendAccessibilityEvent (static_cast<id> ([NSApp mainWindow]),
                                 NSAccessibilityAnnouncementRequestedNotification,
                                 @{ NSAccessibilityAnnouncementKey: juceStringToNS (announcementString),
                                    NSAccessibilityPriorityKey:     @(nsPriority) });

modules/juce_gui_basics/native/accessibility/juce_mac_AccessibilitySharedCode.mm

@@ -46,7 +46,9 @@ public:
     using Holder = std::unique_ptr<Base, AccessibleObjCClassDeleter>;
 
 protected:
-    AccessibleObjCClass()  : ObjCClass<Base> ("JUCEAccessibilityElement_")
+    AccessibleObjCClass() : AccessibleObjCClass ("JUCEAccessibilityElement_") {}
+
+    explicit AccessibleObjCClass (const char* name)  : ObjCClass<Base> (name)
     {
         ObjCClass<Base>::template addIvar<AccessibilityHandler*> ("handler");
     }

modules/juce_gui_basics/widgets/juce_ListBox.cpp

@@ -246,12 +246,7 @@ public:
 
             int getRowIndex() const override
             {
-                const auto index = handler.rowComponent.row;
+                return handler.rowComponent.row;
-
-                if (handler.rowComponent.owner.hasAccessibleHeaderComponent())
-                    return index + 1;
-
-                return index;
             }
 
             int getRowSpan() const override          { return 1; }
@@ -300,23 +295,14 @@ public:
         setViewedComponent (content.release());
     }
 
-    RowComponent* getComponentForRow (int row) const noexcept
+    int getIndexOfFirstVisibleRow() const { return jmax (0, firstIndex - 1); }
-    {
-        if (isPositiveAndBelow (row, rows.size()))
-            return rows[row];
-
-        return nullptr;
-    }
-
-    RowComponent* getComponentForRowWrapped (int row) const noexcept
-    {
-        return rows[row % jmax (1, rows.size())];
-    }
 
     RowComponent* getComponentForRowIfOnscreen (int row) const noexcept
     {
-        return (row >= firstIndex && row < firstIndex + rows.size())
+        const auto startIndex = getIndexOfFirstVisibleRow();
-                 ? getComponentForRowWrapped (row) : nullptr;
+
+        return (startIndex <= row && row < startIndex + rows.size())
+                 ? rows[row % jmax (1, rows.size())] : nullptr;
     }
 
     int getRowNumberOfComponent (Component* const rowComponent) const noexcept
@@ -384,17 +370,20 @@ public:
             firstWholeIndex = (y + rowH - 1) / rowH;
             lastWholeIndex = (y + getMaximumVisibleHeight() - 1) / rowH;
 
-            auto startIndex = jmax (0, firstIndex - 1);
+            const auto startIndex = getIndexOfFirstVisibleRow();
+            const auto lastIndex = startIndex + rows.size();
 
-            for (int i = 0; i < numNeeded; ++i)
+            for (auto row = startIndex; row < lastIndex; ++row)
             {
-                const int row = i + startIndex;
+                if (auto* rowComp = getComponentForRowIfOnscreen (row))
-
-                if (auto* rowComp = getComponentForRowWrapped (row))
                 {
                     rowComp->setBounds (0, row * rowH, w, rowH);
                     rowComp->update (row, owner.isRowSelected (row));
                 }
+                else
+                {
+                    jassertfalse;
+                }
             }
         }
 
@@ -1155,15 +1144,8 @@ std::unique_ptr<AccessibilityHandler> ListBox::createAccessibilityHandler()
         {
             listBox.checkModelPtrIsValid();
 
-            if (listBox.model == nullptr)
+            return listBox.model != nullptr ? listBox.model->getNumRows()
-                return 0;
+                                            : 0;
-
-            const auto numRows = listBox.model->getNumRows();
-
-            if (listBox.hasAccessibleHeaderComponent())
-                return numRows + 1;
-
-            return numRows;
         }
 
         int getNumColumns() const override
@@ -1171,24 +1153,7 @@ std::unique_ptr<AccessibilityHandler> ListBox::createAccessibilityHandler()
             return 1;
         }
 
-        const AccessibilityHandler* getCellHandler (int row, int) const override
+        const AccessibilityHandler* getHeaderHandler() const override
-        {
-            if (auto* headerHandler = getHeaderHandler())
-            {
-                if (row == 0)
-                    return headerHandler;
-
-                --row;
-            }
-
-            if (auto* rowComponent = listBox.viewport->getComponentForRow (row))
-                return rowComponent->getAccessibilityHandler();
-
-            return nullptr;
-        }
-
-    private:
-        const AccessibilityHandler* getHeaderHandler() const
         {
             if (listBox.hasAccessibleHeaderComponent())
                 return listBox.headerComponent->getAccessibilityHandler();
@@ -1196,6 +1161,20 @@ std::unique_ptr<AccessibilityHandler> ListBox::createAccessibilityHandler()
             return nullptr;
         }
 
+        const AccessibilityHandler* getRowHandler (int row) const override
+        {
+            if (auto* rowComponent = listBox.viewport->getComponentForRowIfOnscreen (row))
+                return rowComponent->getAccessibilityHandler();
+
+            return nullptr;
+        }
+
+        const AccessibilityHandler* getCellHandler (int, int) const override
+        {
+            return nullptr;
+        }
+
+    private:
         ListBox& listBox;
 
         JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (TableInterface)

modules/juce_gui_basics/widgets/juce_TableHeaderComponent.cpp

@@ -50,6 +50,7 @@ public:
 //==============================================================================
 TableHeaderComponent::TableHeaderComponent()
 {
+    setFocusContainerType (FocusContainerType::focusContainer);
 }
 
 TableHeaderComponent::~TableHeaderComponent()
@@ -86,7 +87,7 @@ int TableHeaderComponent::getNumColumns (const bool onlyCountVisibleColumns) con
 String TableHeaderComponent::getColumnName (const int columnId) const
 {
     if (auto* ci = getInfoForId (columnId))
-        return ci->name;
+        return ci->getTitle();
 
     return {};
 }
@@ -95,9 +96,9 @@ void TableHeaderComponent::setColumnName (const int columnId, const String& newN
 {
     if (auto* ci = getInfoForId (columnId))
     {
-        if (ci->name != newName)
+        if (ci->getTitle() != newName)
         {
-            ci->name = newName;
+            ci->setTitle (newName);
             sendColumnsChanged();
         }
     }
@@ -116,7 +117,7 @@ void TableHeaderComponent::addColumn (const String& columnName,
     jassert (width > 0);
 
     auto ci = new ColumnInfo();
-    ci->name = columnName;
+    ci->setTitle (columnName);
     ci->id = columnId;
     ci->width = width;
     ci->lastDeliberateWidth = width;
@@ -125,7 +126,11 @@ void TableHeaderComponent::addColumn (const String& columnName,
     jassert (ci->maximumWidth >= ci->minimumWidth);
     ci->propertyFlags = propertyFlags;
 
-    columns.insert (insertIndex, ci);
+    auto* added = columns.insert (insertIndex, ci);
+    addChildComponent (added);
+    added->setVisible ((propertyFlags & visible) != 0);
+
+    resized();
     sendColumnsChanged();
 }
 
@@ -197,6 +202,7 @@ void TableHeaderComponent::setColumnWidth (const int columnId, const int newWidt
                 }
             }
 
+            resized();
             repaint();
             columnsResized = true;
             triggerAsyncUpdate();
@@ -340,6 +346,7 @@ void TableHeaderComponent::resizeColumnsToFit (int firstColumnIndex, int targetT
             if (newWidth != ci->width)
             {
                 ci->width = newWidth;
+                resized();
                 repaint();
                 columnsResized = true;
                 triggerAsyncUpdate();
@@ -354,11 +361,7 @@ void TableHeaderComponent::setColumnVisible (const int columnId, const bool shou
     {
         if (shouldBeVisible != ci->isVisible())
         {
-            if (shouldBeVisible)
+            ci->setVisible (shouldBeVisible);
-                ci->propertyFlags |= visible;
-            else
-                ci->propertyFlags &= ~visible;
-
             sendColumnsChanged();
             resized();
         }
@@ -409,6 +412,7 @@ bool TableHeaderComponent::isSortedForwards() const
 void TableHeaderComponent::reSortTable()
 {
     sortChanged = true;
+    resized();
     repaint();
     triggerAsyncUpdate();
 }
@@ -485,7 +489,7 @@ void TableHeaderComponent::addMenuItems (PopupMenu& menu, const int /*columnIdCl
 {
     for (auto* ci : columns)
         if ((ci->propertyFlags & appearsOnColumnMenu) != 0)
-            menu.addItem (ci->id, ci->name,
+            menu.addItem (ci->id, ci->getTitle(),
                           (ci->propertyFlags & (sortedForwards | sortedBackwards)) == 0,
                           isColumnVisible (ci->id));
 }
@@ -502,28 +506,42 @@ void TableHeaderComponent::paint (Graphics& g)
 
     lf.drawTableHeaderBackground (g, *this);
 
-    auto clip = g.getClipBounds();
+    for (auto* ci : columns)
+    {
+        if (ci->isVisible() && ci->getWidth() > 0)
+        {
+            Graphics::ScopedSaveState ss (g);
+
+            g.setOrigin (ci->getX(), ci->getY());
+            g.reduceClipRegion (0, 0, ci->getWidth(), ci->getHeight());
+
+            lf.drawTableHeaderColumn (g, *this, ci->getTitle(), ci->id, ci->width, getHeight(),
+                                      ci->id == columnIdUnderMouse,
+                                      ci->id == columnIdUnderMouse && isMouseButtonDown(),
+                                      ci->propertyFlags);
+        }
+    }
+}
+
+void TableHeaderComponent::resized()
+{
+    auto clip = getBounds();
 
     int x = 0;
 
+    for (auto* ci : columns)
+        ci->setBounds (0, 0, 0, 0);
+
     for (auto* ci : columns)
     {
         if (ci->isVisible())
         {
             if (x + ci->width > clip.getX()
-                 && (ci->id != columnIdBeingDragged
+                && (ci->id != columnIdBeingDragged
-                      || dragOverlayComp == nullptr
+                    || dragOverlayComp == nullptr
-                      || ! dragOverlayComp->isVisible()))
+                    || ! dragOverlayComp->isVisible()))
             {
-                Graphics::ScopedSaveState ss (g);
+                ci->setBounds (x, 0, ci->width, getHeight());
-
-                g.setOrigin (x, 0);
-                g.reduceClipRegion (0, 0, ci->width, getHeight());
-
-                lf.drawTableHeaderColumn (g, *this, ci->name, ci->id, ci->width, getHeight(),
-                                          ci->id == columnIdUnderMouse,
-                                          ci->id == columnIdUnderMouse && isMouseButtonDown(),
-                                          ci->propertyFlags);
             }
 
             x += ci->width;
@@ -540,6 +558,7 @@ void TableHeaderComponent::mouseExit  (const MouseEvent&)    { setColumnUnderMou
 
 void TableHeaderComponent::mouseDown (const MouseEvent& e)
 {
+    resized();
     repaint();
     columnIdBeingResized = 0;
     columnIdBeingDragged = 0;
@@ -716,6 +735,7 @@ void TableHeaderComponent::endDrag (const int finalIndex)
         moveColumn (columnIdBeingDragged, finalIndex);
 
         columnIdBeingDragged = 0;
+        resized();
         repaint();
 
         for (int i = listeners.size(); --i >= 0;)
@@ -735,6 +755,7 @@ void TableHeaderComponent::mouseUp (const MouseEvent& e)
             c->lastDeliberateWidth = c->width;
 
     columnIdBeingResized = 0;
+    resized();
     repaint();
 
     endDrag (getIndexOfColumnId (columnIdBeingDragged, true));
@@ -756,10 +777,6 @@ MouseCursor TableHeaderComponent::getMouseCursor()
 }
 
 //==============================================================================
-bool TableHeaderComponent::ColumnInfo::isVisible() const
-{
-    return (propertyFlags & TableHeaderComponent::visible) != 0;
-}
 
 TableHeaderComponent::ColumnInfo* TableHeaderComponent::getInfoForId (int id) const
 {
@@ -793,6 +810,7 @@ void TableHeaderComponent::sendColumnsChanged()
     if (stretchToFit && lastDeliberateWidth > 0)
         resizeAllColumnsToFit (lastDeliberateWidth);
 
+    resized();
     repaint();
     columnsChanged = true;
     triggerAsyncUpdate();
@@ -903,4 +921,9 @@ std::unique_ptr<AccessibilityHandler> TableHeaderComponent::createAccessibilityH
     return std::make_unique<AccessibilityHandler> (*this, AccessibilityRole::tableHeader);
 }
 
+std::unique_ptr<AccessibilityHandler> TableHeaderComponent::ColumnInfo::createAccessibilityHandler()
+{
+    return std::make_unique<AccessibilityHandler> (*this, AccessibilityRole::tableHeader);
+}
+
 } // namespace juce

modules/juce_gui_basics/widgets/juce_TableHeaderComponent.h

@@ -403,6 +403,8 @@ public:
     /** @internal */
     void paint (Graphics&) override;
     /** @internal */
+    void resized() override;
+    /** @internal */
     void mouseMove (const MouseEvent&) override;
     /** @internal */
     void mouseEnter (const MouseEvent&) override;
@@ -421,13 +423,13 @@ public:
     virtual void showColumnChooserMenu (int columnIdClicked);
 
 private:
-    struct ColumnInfo
+    struct ColumnInfo : public Component
     {
-        String name;
+        ColumnInfo() { setInterceptsMouseClicks (false, false); }
+        std::unique_ptr<AccessibilityHandler> createAccessibilityHandler() override;
+
         int id, propertyFlags, width, minimumWidth, maximumWidth;
         double lastDeliberateWidth;
-
-        bool isVisible() const;
     };
 
     OwnedArray<ColumnInfo> columns;

modules/juce_gui_basics/widgets/juce_TableListBox.cpp

@@ -26,6 +26,9 @@
 namespace juce
 {
 
+static const Identifier tableColumnProperty { "_tableColumnId" };
+static const Identifier tableAccessiblePlaceholderProperty { "_accessiblePlaceholder" };
+
 class TableListBox::RowComp   : public Component,
                                 public TooltipClient
 {
@@ -48,7 +51,7 @@ public:
 
             for (int i = 0; i < numColumns; ++i)
             {
-                if (columnComponents[i] == nullptr)
+                if (columnComponents[(size_t) i]->getProperties().contains (tableAccessiblePlaceholderProperty))
                 {
                     auto columnRect = headerComp.getColumnPosition (i).withHeight (getHeight());
 
@@ -86,33 +89,48 @@ public:
 
         if (tableModel != nullptr && row < owner.getNumRows())
         {
-            const Identifier columnProperty ("_tableColumnId");
+            const auto numColumns = owner.getHeader().getNumColumns (true);
-            auto numColumns = owner.getHeader().getNumColumns (true);
+            columnComponents.resize ((size_t) numColumns);
 
             for (int i = 0; i < numColumns; ++i)
             {
                 auto columnId = owner.getHeader().getColumnIdOfIndex (i, true);
-                auto* comp = columnComponents[i];
+                auto originalComp = std::move (columnComponents[(size_t) i]);
+                auto oldCustomComp = originalComp != nullptr && ! originalComp->getProperties().contains (tableAccessiblePlaceholderProperty)
+                                   ? std::move (originalComp)
+                                   : nullptr;
+                auto compToRefresh = oldCustomComp != nullptr && columnId == static_cast<int> (oldCustomComp->getProperties()[tableColumnProperty])
+                                   ? std::move (oldCustomComp)
+                                   : nullptr;
+                auto newCustomComp = rawToUniquePtr (tableModel->refreshComponentForCell (row, columnId, isSelected, compToRefresh.release()));
 
-                if (comp != nullptr && columnId != static_cast<int> (comp->getProperties() [columnProperty]))
+                auto columnComp = [&]
                 {
-                    columnComponents.set (i, nullptr);
+                    // We got a result from refreshComponentForCell, so use that
-                    comp = nullptr;
+                    if (newCustomComp != nullptr)
-                }
+                        return std::move (newCustomComp);
 
-                comp = tableModel->refreshComponentForCell (row, columnId, isSelected, comp);
+                    // There was already a placeholder component for this column
-                columnComponents.set (i, comp, false);
+                    if (originalComp != nullptr)
+                        return std::move (originalComp);
 
-                if (comp != nullptr)
+                    // Create a new placeholder component to use
-                {
+                    auto comp = std::make_unique<Component>();
-                    comp->getProperties().set (columnProperty, columnId);
+                    comp->setInterceptsMouseClicks (false, false);
+                    comp->getProperties().set (tableAccessiblePlaceholderProperty, true);
+                    return comp;
+                }();
 
-                    addAndMakeVisible (comp);
+                // In order for navigation to work correctly on macOS, the number of child
-                    resizeCustomComp (i);
+                // accessibility elements on each row must match the number of header accessibility
-                }
+                // elements.
+                columnComp->setFocusContainerType (FocusContainerType::focusContainer);
+                columnComp->getProperties().set (tableColumnProperty, columnId);
+                addAndMakeVisible (*columnComp);
+
+                columnComponents[(size_t) i] = std::move (columnComp);
+                resizeCustomComp (i);
             }
-
-            columnComponents.removeRange (numColumns, columnComponents.size());
         }
         else
         {
@@ -122,15 +140,19 @@ public:
 
     void resized() override
     {
-        for (int i = columnComponents.size(); --i >= 0;)
+        for (auto i = (int) columnComponents.size(); --i >= 0;)
             resizeCustomComp (i);
     }
 
     void resizeCustomComp (int index)
     {
-        if (auto* c = columnComponents.getUnchecked (index))
+        if (auto& c = columnComponents[(size_t) index])
-            c->setBounds (owner.getHeader().getColumnPosition (index)
+        {
-                            .withY (0).withHeight (getHeight()));
+            c->setBounds (owner.getHeader()
+                               .getColumnPosition (index)
+                               .withY (0)
+                               .withHeight (getHeight()));
+        }
     }
 
     void mouseDown (const MouseEvent& e) override
@@ -220,7 +242,12 @@ public:
 
     Component* findChildComponentForColumn (int columnId) const
     {
-        return columnComponents [owner.getHeader().getIndexOfColumnId (columnId, true)];
+        const auto index = (size_t) owner.getHeader().getIndexOfColumnId (columnId, true);
+
+        if (isPositiveAndBelow (index, columnComponents.size()))
+            return columnComponents[index].get();
+
+        return nullptr;
     }
 
     std::unique_ptr<AccessibilityHandler> createAccessibilityHandler() override
@@ -298,7 +325,7 @@ public:
 
     //==============================================================================
     TableListBox& owner;
-    OwnedArray<Component> columnComponents;
+    std::vector<std::unique_ptr<Component>> columnComponents;
     int row = -1;
     bool isSelected = false, isDragging = false, selectRowOnMouseUp = false;
 
@@ -567,17 +594,28 @@ std::unique_ptr<AccessibilityHandler> TableListBox::createAccessibilityHandler()
             return tableListBox.getHeader().getNumColumns (false);
         }
 
-        const AccessibilityHandler* getCellHandler (int row, int column) const override
+        const AccessibilityHandler* getRowHandler (int row) const override
         {
             if (isPositiveAndBelow (row, getNumRows()))
-            {
-                if (isPositiveAndBelow (column, getNumColumns()))
-                    if (auto* cellComponent = tableListBox.getCellComponent (tableListBox.getHeader().getColumnIdOfIndex (column, false), row))
-                        return cellComponent->getAccessibilityHandler();
-
                 if (auto* rowComp = tableListBox.getComponentForRowNumber (row))
                     return rowComp->getAccessibilityHandler();
-            }
+
+            return nullptr;
+        }
+
+        const AccessibilityHandler* getCellHandler (int row, int column) const override
+        {
+            if (isPositiveAndBelow (row, getNumRows()) && isPositiveAndBelow (column, getNumColumns()))
+                if (auto* cellComponent = tableListBox.getCellComponent (tableListBox.getHeader().getColumnIdOfIndex (column, false), row))
+                    return cellComponent->getAccessibilityHandler();
+
+            return nullptr;
+        }
+
+        const AccessibilityHandler* getHeaderHandler() const override
+        {
+            if (tableListBox.hasAccessibleHeaderComponent())
+                return tableListBox.headerComponent->getAccessibilityHandler();
 
             return nullptr;
         }

modules/juce_gui_basics/widgets/juce_TreeView.cpp

@@ -1448,7 +1448,12 @@ std::unique_ptr<AccessibilityHandler> TreeView::createAccessibilityHandler()
         int getNumRows() const override     { return treeView.getNumRowsInTree(); }
         int getNumColumns() const override  { return 1; }
 
-        const AccessibilityHandler* getCellHandler (int row, int) const override
+        const AccessibilityHandler* getHeaderHandler() const override
+        {
+            return nullptr;
+        }
+
+        const AccessibilityHandler* getRowHandler (int row) const override
         {
             if (auto* itemComp = treeView.getItemComponent (treeView.getItemOnRow (row)))
                 return itemComp->getAccessibilityHandler();
@@ -1456,6 +1461,11 @@ std::unique_ptr<AccessibilityHandler> TreeView::createAccessibilityHandler()
             return nullptr;
         }
 
+        const AccessibilityHandler* getCellHandler (int, int) const override
+        {
+            return nullptr;
+        }
+
     private:
         TreeView& treeView;