Added an option for Viewport subclasses to create custom scrollbars. Also modified Viewport::getVerticalScrollBar() and ListBox::getVerticalScrollBar() to return references instead of pointers

examples/audio plugin host/Source/FilterIOConfiguration.cpp

@@ -23,15 +23,18 @@
 
   ==============================================================================
 */
+
 #include "../JuceLibraryCode/JuceHeader.h"
 #include "GraphEditorPanel.h"
 #include "InternalFilters.h"
 #include "MainHostWindow.h"
-
 #include "FilterIOConfiguration.h"
 
+
 //==============================================================================
-class NumberedBoxes : public TableListBox, private TableListBoxModel, private Button::Listener
+class NumberedBoxes   : public TableListBox,
+                        private TableListBoxModel,
+                        private Button::Listener
 {
 public:
     struct Listener
@@ -56,21 +59,19 @@ public:
           canAddColumn (canCurrentlyAddColumn),
           canRemoveColumn (canCurrentlyRemoveColumn)
     {
-        TableHeaderComponent& tableHeader = getHeader();
+        auto& tableHeader = getHeader();
 
         for (int i = 0; i < 16; ++i)
             tableHeader.addColumn (String (i + 1), i + 1, 40);
 
         setHeaderHeight (0);
         setRowHeight (40);
-
-        if (ScrollBar* scrollbar = getHorizontalScrollBar())
-            scrollbar->setAutoHide (false);
+        getHorizontalScrollBar().setAutoHide (false);
     }
 
     void setSelected (int columnId)
     {
-        if (TextButton* button = dynamic_cast<TextButton*> (getCellComponent (columnId, 0)))
+        if (auto* button = dynamic_cast<TextButton*> (getCellComponent (columnId, 0)))
             button->setToggleState (true, NotificationType::dontSendNotification);
     }
 
@@ -80,7 +81,7 @@ public:
         {
             canAddColumn = canCurrentlyAdd;
 
-            if (TextButton* button = dynamic_cast<TextButton*> (getCellComponent (plusButtonColumnId, 0)))
+            if (auto* button = dynamic_cast<TextButton*> (getCellComponent (plusButtonColumnId, 0)))
                 button->setEnabled (true);
         }
     }
@@ -91,7 +92,7 @@ public:
         {
             canRemoveColumn = canCurrentlyRemove;
 
-            if (TextButton* button = dynamic_cast<TextButton*> (getCellComponent (minusButtonColumnId, 0)))
+            if (auto* button = dynamic_cast<TextButton*> (getCellComponent (minusButtonColumnId, 0)))
                 button->setEnabled (true);
         }
     }
@@ -105,9 +106,10 @@ private:
     Component* refreshComponentForCell (int, int columnId, bool,
                                         Component* existingComponentToUpdate) override
     {
-        TextButton* textButton = dynamic_cast<TextButton*> (existingComponentToUpdate);
+        auto* textButton = dynamic_cast<TextButton*> (existingComponentToUpdate);
+
         if (textButton == nullptr)
-            textButton = new TextButton ("");
+            textButton = new TextButton();
 
         textButton->setButtonText (getButtonName (columnId));
         textButton->setConnectedEdges (Button::ConnectedOnLeft | Button::ConnectedOnRight |
@@ -124,7 +126,7 @@ private:
             textButton->setRadioGroupId (1, NotificationType::dontSendNotification);
             textButton->setClickingTogglesState (true);
 
-            Colour busColour = Colours::green.withRotatedHue (static_cast<float> (columnId) / 5.0f);
+            auto busColour = Colours::green.withRotatedHue (static_cast<float> (columnId) / 5.0f);
             textButton->setColour (TextButton::buttonColourId, busColour);
             textButton->setColour (TextButton::buttonOnColourId, busColour.withMultipliedBrightness (2.0f));
         }
@@ -145,17 +147,18 @@ private:
 
     void buttonClicked (Button* btn) override
     {
-        const String& text = btn->getButtonText();
+        auto text = btn->getButtonText();
 
-        if      (text == "+") listener.addColumn();
-        else if (text == "-") listener.removeColumn();
+        if (text == "+") listener.addColumn();
+        if (text == "-") listener.removeColumn();
     }
 
     void buttonStateChanged (Button* btn) override
     {
-        const String& text = btn->getButtonText();
+        auto text = btn->getButtonText();
 
-        if (text == "+" || text == "-") return;
+        if (text == "+" || text == "-")
+            return;
 
         if (btn->getToggleState())
             listener.columnSelected (text.getIntValue());
@@ -167,8 +170,10 @@ private:
 };
 
 //==============================================================================
-class FilterIOConfigurationWindow::InputOutputConfig
-     : public Component, private ComboBox::Listener, private Button::Listener, private NumberedBoxes::Listener
+class FilterIOConfigurationWindow::InputOutputConfig  : public Component,
+                                                        private ComboBox::Listener,
+                                                        private Button::Listener,
+                                                        private NumberedBoxes::Listener
 {
 public:
     InputOutputConfig (FilterIOConfigurationWindow& parent, bool direction)
@@ -208,7 +213,7 @@ public:
 
     void resized() override
     {
-        Rectangle<int> r = getLocalBounds().reduced (10);
+        auto r = getLocalBounds().reduced (10);
 
         ioTitle.setBounds (r.removeFromTop (14));
         r.reduce (10, 0);
@@ -217,7 +222,7 @@ public:
         ioBuses.setBounds (r.removeFromTop (60));
 
         {
-            Rectangle<int> label = r.removeFromTop (24);
+            auto label = r.removeFromTop (24);
 
             nameLabel.setBounds (label.removeFromLeft (100));
             enabledToggle.setBounds (label.removeFromRight (80));
@@ -225,7 +230,7 @@ public:
         }
 
         {
-            Rectangle<int> label = r.removeFromTop (24);
+            auto label = r.removeFromTop (24);
 
             layoutLabel.setBounds (label.removeFromLeft (100));
             layouts.setBounds (label);
@@ -235,12 +240,13 @@ public:
 private:
     void updateBusButtons()
     {
-        if (AudioProcessor* filter = owner.getAudioProcessor())
+        if (auto* filter = owner.getAudioProcessor())
         {
-            TableHeaderComponent& header = ioBuses.getHeader();
+            auto& header = ioBuses.getHeader();
             header.removeAllColumns();
 
             const int n = filter->getBusCount (isInput);
+
             for (int i = 0; i < n; ++i)
                 header.addColumn ("", i + 1, 40);
 
@@ -256,14 +262,13 @@ private:
 
     void updateBusLayout()
     {
-        if (AudioProcessor* filter = owner.getAudioProcessor())
+        if (auto* filter = owner.getAudioProcessor())
         {
-            if (AudioProcessor::Bus* bus = filter->getBus (isInput, currentBus))
+            if (auto* bus = filter->getBus (isInput, currentBus))
             {
                 name.setText (bus->getName(), NotificationType::dontSendNotification);
 
                 int i;
-
                 for (i = 1; i < AudioChannelSet::maxChannelsOfNamedLayout; ++i)
                     if ((layouts.indexOfItemId(i) == -1) != bus->supportedLayoutWithChannels (i).isDisabled())
                         break;
@@ -275,7 +280,8 @@ private:
 
                     for (i = 1; i < AudioChannelSet::maxChannelsOfNamedLayout; ++i)
                     {
-                        AudioChannelSet set = bus->supportedLayoutWithChannels (i);
+                        auto set = bus->supportedLayoutWithChannels (i);
+
                         if (! set.isDisabled())
                             layouts.addItem (set.getDescription(), i);
                     }
@@ -298,18 +304,18 @@ private:
     {
         if (combo == &layouts)
         {
-            if (AudioProcessor* filter = owner.getAudioProcessor())
+            if (auto* processor = owner.getAudioProcessor())
             {
-                if (AudioProcessor::Bus* bus = filter->getBus (isInput, currentBus))
+                if (auto* bus = processor->getBus (isInput, currentBus))
                 {
-                    const int selectedNumChannels = layouts.getSelectedId();
+                    auto selectedNumChannels = layouts.getSelectedId();
 
                     if (selectedNumChannels != bus->getLastEnabledLayout().size())
                     {
                         if (isPositiveAndBelow (selectedNumChannels, (int) AudioChannelSet::maxChannelsOfNamedLayout)
-                         && bus->setCurrentLayoutWithoutEnabling (bus->supportedLayoutWithChannels (selectedNumChannels)))
+                             && bus->setCurrentLayoutWithoutEnabling (bus->supportedLayoutWithChannels (selectedNumChannels)))
                         {
-                            if (InputOutputConfig* config = owner.getConfig (! isInput))
+                            if (auto* config = owner.getConfig (! isInput))
                                 config->updateBusLayout();
 
                             owner.update();
@@ -326,9 +332,9 @@ private:
     {
         if (btn == &enabledToggle && enabledToggle.isEnabled())
         {
-            if (AudioProcessor* filter = owner.getAudioProcessor())
+            if (auto* processor = owner.getAudioProcessor())
             {
-                if (AudioProcessor::Bus* bus = filter->getBus (isInput, currentBus))
+                if (auto* bus = processor->getBus (isInput, currentBus))
                 {
                     if (bus->isEnabled() != enabledToggle.getToggleState())
                     {
@@ -362,16 +368,16 @@ private:
     //==============================================================================
     void addColumn() override
     {
-        if (AudioProcessor* filter = owner.getAudioProcessor())
+        if (auto* processor = owner.getAudioProcessor())
         {
-            if (filter->canAddBus (isInput))
+            if (processor->canAddBus (isInput))
             {
-                if (filter->addBus (isInput))
+                if (processor->addBus (isInput))
                 {
                     updateBusButtons();
                     updateBusLayout();
 
-                    if (InputOutputConfig* config = owner.getConfig (! isInput))
+                    if (auto* config = owner.getConfig (! isInput))
                     {
                         config->updateBusButtons();
                         config->updateBusLayout();
@@ -385,18 +391,18 @@ private:
 
     void removeColumn() override
     {
-        if (AudioProcessor* filter = owner.getAudioProcessor())
+        if (auto* processor = owner.getAudioProcessor())
         {
-            if (filter->getBusCount (isInput) > 1 && filter->canRemoveBus (isInput))
+            if (processor->getBusCount (isInput) > 1 && processor->canRemoveBus (isInput))
             {
-                if (filter->removeBus (isInput))
+                if (processor->removeBus (isInput))
                 {
-                    currentBus = jmin (filter->getBusCount (isInput) - 1, currentBus);
+                    currentBus = jmin (processor->getBusCount (isInput) - 1, currentBus);
 
                     updateBusButtons();
                     updateBusLayout();
 
-                    if (InputOutputConfig* config = owner.getConfig (! isInput))
+                    if (auto* config = owner.getConfig (! isInput))
                     {
                         config->updateBusButtons();
                         config->updateBusLayout();
@@ -411,6 +417,7 @@ private:
     void columnSelected (int columnId) override
     {
         const int newBus = columnId - 1;
+
         if (currentBus != newBus)
         {
             currentBus = newBus;
@@ -460,9 +467,9 @@ FilterIOConfigurationWindow::FilterIOConfigurationWindow (AudioProcessor* const
 
 FilterIOConfigurationWindow::~FilterIOConfigurationWindow()
 {
-    if (AudioProcessorGraph* graph = getGraph())
+    if (auto* graph = getGraph())
     {
-        if (AudioProcessor* p = getAudioProcessor())
+        if (auto* p = getAudioProcessor())
         {
             ScopedLock renderLock (graph->getCallbackLock());
 
@@ -485,7 +492,7 @@ void FilterIOConfigurationWindow::paint (Graphics& g)
 
 void FilterIOConfigurationWindow::resized()
 {
-    Rectangle<int> r = getLocalBounds().reduced (10);
+    auto r = getLocalBounds().reduced (10);
 
     title.setBounds (r.removeFromTop (14));
     r.reduce (10, 0);
@@ -499,25 +506,25 @@ void FilterIOConfigurationWindow::resized()
 
 void FilterIOConfigurationWindow::update()
 {
-    const int32 nodeId = getNodeId();
+    auto nodeId = getNodeId();
 
-    if (AudioProcessorGraph* graph = getGraph())
+    if (auto* graph = getGraph())
         if (nodeId != -1)
             graph->disconnectNode (static_cast<uint32> (nodeId));
 
-    if (GraphDocumentComponent* graphEditor = getGraphEditor())
-        if (GraphEditorPanel* panel = graphEditor->graphPanel)
+    if (auto* graphEditor = getGraphEditor())
+        if (auto* panel = graphEditor->graphPanel)
             panel->updateComponents();
 }
 
 int32 FilterIOConfigurationWindow::getNodeId() const
 {
-    if (AudioProcessorGraph* graph = getGraph())
+    if (auto* graph = getGraph())
     {
         const int n = graph->getNumNodes();
 
         for (int i = 0; i < n; ++i)
-            if (AudioProcessorGraph::Node* node = graph->getNode (i))
+            if (auto* node = graph->getNode (i))
                 if (node->getProcessor() == getAudioProcessor())
                     return static_cast<int32> (node->nodeId);
     }
@@ -530,7 +537,7 @@ MainHostWindow* FilterIOConfigurationWindow::getMainWindow() const
     Component* comp;
 
     for (int idx = 0; (comp = Desktop::getInstance().getComponent(idx)) != nullptr; ++idx)
-        if (MainHostWindow* mainWindow = dynamic_cast<MainHostWindow*> (comp))
+        if (auto* mainWindow = dynamic_cast<MainHostWindow*> (comp))
             return mainWindow;
 
     return nullptr;
@@ -538,20 +545,18 @@ MainHostWindow* FilterIOConfigurationWindow::getMainWindow() const
 
 GraphDocumentComponent* FilterIOConfigurationWindow::getGraphEditor() const
 {
-    if (MainHostWindow* mainWindow = getMainWindow())
-    {
-        if (GraphDocumentComponent* graphEditor = mainWindow->getGraphEditor())
+    if (auto* mainWindow = getMainWindow())
+        if (auto* graphEditor = mainWindow->getGraphEditor())
             return graphEditor;
-    }
 
     return nullptr;
 }
 
 AudioProcessorGraph* FilterIOConfigurationWindow::getGraph() const
 {
-    if (GraphDocumentComponent* graphEditor = getGraphEditor())
-        if (FilterGraph* filterGraph = graphEditor->graph)
-            return &filterGraph->getGraph();
+    if (auto* graphEditor = getGraphEditor())
+        if (auto* graph = graphEditor->graph.get())
+            return &graph->getGraph();
 
     return nullptr;
 }

modules/juce_gui_basics/filebrowser/juce_FileListComponent.cpp

@@ -61,7 +61,7 @@ void FileListComponent::deselectAllFiles()
 
 void FileListComponent::scrollToTop()
 {
-    getVerticalScrollBar()->setCurrentRangeStart (0);
+    getVerticalScrollBar().setCurrentRangeStart (0);
 }
 
 void FileListComponent::setSelectedFile (const File& f)

modules/juce_gui_basics/filebrowser/juce_FileTreeComponent.cpp

@@ -91,7 +91,7 @@ public:
                 {
                     jassert (parentContentsList != nullptr);
 
-                    DirectoryContentsList* const l = new DirectoryContentsList (parentContentsList->getFilter(), thread);
+                    auto l = new DirectoryContentsList (parentContentsList->getFilter(), thread);
 
                     l->setDirectory (file,
                                      parentContentsList->isFindingDirectories(),
@@ -299,7 +299,7 @@ void FileTreeComponent::deselectAllFiles()
 
 void FileTreeComponent::scrollToTop()
 {
-    getViewport()->getVerticalScrollBar()->setCurrentRangeStart (0);
+    getViewport()->getVerticalScrollBar().setCurrentRangeStart (0);
 }
 
 void FileTreeComponent::setDragAndDropDescription (const String& description)

modules/juce_gui_basics/layout/juce_Viewport.cpp

@@ -35,11 +35,11 @@ Viewport::Viewport (const String& name)  : Component (name)
 
     scrollBarThickness = getLookAndFeel().getDefaultScrollbarWidth();
 
-    addChildComponent (verticalScrollBar);
-    addChildComponent (horizontalScrollBar);
+    addChildComponent (verticalScrollBar   = createScrollBarComponent (true));
+    addChildComponent (horizontalScrollBar = createScrollBarComponent (false));
 
-    verticalScrollBar.addListener (this);
-    horizontalScrollBar.addListener (this);
+    getVerticalScrollBar().addListener (this);
+    getHorizontalScrollBar().addListener (this);
 
     setInterceptsMouseClicks (false, true);
     setWantsKeyboardFocus (true);
@@ -140,7 +140,7 @@ bool Viewport::autoScroll (const int mouseX, const int mouseY, const int activeB
     {
         int dx = 0, dy = 0;
 
-        if (horizontalScrollBar.isVisible() || canScrollHorizontally())
+        if (getHorizontalScrollBar().isVisible() || canScrollHorizontally())
         {
             if (mouseX < activeBorderThickness)
                 dx = activeBorderThickness - mouseX;
@@ -153,7 +153,7 @@ bool Viewport::autoScroll (const int mouseX, const int mouseY, const int activeB
                 dx = jmin (dx, maximumSpeed, -contentComp->getX());
         }
 
-        if (verticalScrollBar.isVisible() || canScrollVertically())
+        if (getVerticalScrollBar().isVisible() || canScrollVertically())
         {
             if (mouseY < activeBorderThickness)
                 dy = activeBorderThickness - mouseY;
@@ -223,7 +223,7 @@ struct Viewport::DragToScrollListener   : private MouseListener,
     {
         if (numTouches == 1 && ! isViewportDragBlocked)
         {
-            Point<float> totalOffset = e.getOffsetFromDragStart().toFloat();
+            auto totalOffset = e.getOffsetFromDragStart().toFloat();
 
             if (! isDragging && totalOffset.getDistanceFromOrigin() > 8.0f)
             {
@@ -326,8 +326,8 @@ void Viewport::updateVisibleArea()
 
     for (int i = 3; --i >= 0;)
     {
-        hBarVisible = canShowHBar && ! horizontalScrollBar.autoHides();
-        vBarVisible = canShowVBar && ! verticalScrollBar.autoHides();
+        hBarVisible = canShowHBar && ! getHorizontalScrollBar().autoHides();
+        vBarVisible = canShowVBar && ! getVerticalScrollBar().autoHides();
         contentArea = getLocalBounds();
 
         if (contentComp != nullptr && ! contentArea.contains (contentComp->getBounds()))
@@ -371,27 +371,30 @@ void Viewport::updateVisibleArea()
 
     auto visibleOrigin = -contentBounds.getPosition();
 
-    horizontalScrollBar.setBounds (0, contentArea.getHeight(), contentArea.getWidth(), scrollbarWidth);
-    horizontalScrollBar.setRangeLimits (0.0, contentBounds.getWidth());
-    horizontalScrollBar.setCurrentRange (visibleOrigin.x, contentArea.getWidth());
-    horizontalScrollBar.setSingleStepSize (singleStepX);
-    horizontalScrollBar.cancelPendingUpdate();
+    auto& hbar = getHorizontalScrollBar();
+    auto& vbar = getVerticalScrollBar();
+
+    hbar.setBounds (0, contentArea.getHeight(), contentArea.getWidth(), scrollbarWidth);
+    hbar.setRangeLimits (0.0, contentBounds.getWidth());
+    hbar.setCurrentRange (visibleOrigin.x, contentArea.getWidth());
+    hbar.setSingleStepSize (singleStepX);
+    hbar.cancelPendingUpdate();
 
     if (canShowHBar && ! hBarVisible)
         visibleOrigin.setX (0);
 
-    verticalScrollBar.setBounds (contentArea.getWidth(), 0, scrollbarWidth, contentArea.getHeight());
-    verticalScrollBar.setRangeLimits (0.0, contentBounds.getHeight());
-    verticalScrollBar.setCurrentRange (visibleOrigin.y, contentArea.getHeight());
-    verticalScrollBar.setSingleStepSize (singleStepY);
-    verticalScrollBar.cancelPendingUpdate();
+    vbar.setBounds (contentArea.getWidth(), 0, scrollbarWidth, contentArea.getHeight());
+    vbar.setRangeLimits (0.0, contentBounds.getHeight());
+    vbar.setCurrentRange (visibleOrigin.y, contentArea.getHeight());
+    vbar.setSingleStepSize (singleStepY);
+    vbar.cancelPendingUpdate();
 
     if (canShowVBar && ! vBarVisible)
         visibleOrigin.setY (0);
 
     // Force the visibility *after* setting the ranges to avoid flicker caused by edge conditions in the numbers.
-    horizontalScrollBar.setVisible (hBarVisible);
-    verticalScrollBar.setVisible (vBarVisible);
+    hbar.setVisible (hBarVisible);
+    vbar.setVisible (vBarVisible);
 
     if (contentComp != nullptr)
     {
@@ -414,8 +417,8 @@ void Viewport::updateVisibleArea()
         visibleAreaChanged (visibleArea);
     }
 
-    horizontalScrollBar.handleUpdateNowIfNeeded();
-    verticalScrollBar.handleUpdateNowIfNeeded();
+    hbar.handleUpdateNowIfNeeded();
+    vbar.handleUpdateNowIfNeeded();
 }
 
 //==============================================================================
@@ -480,11 +483,11 @@ void Viewport::scrollBarMoved (ScrollBar* scrollBarThatHasMoved, double newRange
 {
     const int newRangeStartInt = roundToInt (newRangeStart);
 
-    if (scrollBarThatHasMoved == &horizontalScrollBar)
+    if (scrollBarThatHasMoved == horizontalScrollBar)
     {
         setViewPosition (newRangeStartInt, getViewPositionY());
     }
-    else if (scrollBarThatHasMoved == &verticalScrollBar)
+    else if (scrollBarThatHasMoved == verticalScrollBar)
     {
         setViewPosition (getViewPositionX(), newRangeStartInt);
     }
@@ -511,8 +514,8 @@ bool Viewport::useMouseWheelMoveIfNeeded (const MouseEvent& e, const MouseWheelD
 {
     if (! (e.mods.isAltDown() || e.mods.isCtrlDown() || e.mods.isCommandDown()))
     {
-        const bool canScrollVert = (allowScrollingWithoutScrollbarV || verticalScrollBar.isVisible());
-        const bool canScrollHorz = (allowScrollingWithoutScrollbarH || horizontalScrollBar.isVisible());
+        const bool canScrollVert = (allowScrollingWithoutScrollbarV || getVerticalScrollBar().isVisible());
+        const bool canScrollHorz = (allowScrollingWithoutScrollbarH || getHorizontalScrollBar().isVisible());
 
         if (canScrollHorz || canScrollVert)
         {
@@ -566,13 +569,13 @@ bool Viewport::keyPressed (const KeyPress& key)
 {
     const bool isUpDownKey = isUpDownKeyPress (key);
 
-    if (verticalScrollBar.isVisible() && isUpDownKey)
-        return verticalScrollBar.keyPressed (key);
+    if (getVerticalScrollBar().isVisible() && isUpDownKey)
+        return getVerticalScrollBar().keyPressed (key);
 
     const bool isLeftRightKey = isLeftRightKeyPress (key);
 
-    if (horizontalScrollBar.isVisible() && (isUpDownKey || isLeftRightKey))
-        return horizontalScrollBar.keyPressed (key);
+    if (getHorizontalScrollBar().isVisible() && (isUpDownKey || isLeftRightKey))
+        return getHorizontalScrollBar().keyPressed (key);
 
     return false;
 }
@@ -582,4 +585,9 @@ bool Viewport::respondsToKey (const KeyPress& key)
     return isUpDownKeyPress (key) || isLeftRightKeyPress (key);
 }
 
+ScrollBar* Viewport::createScrollBarComponent (bool isVertical)
+{
+    return new ScrollBar (isVertical);
+}
+
 } // namespace juce

modules/juce_gui_basics/layout/juce_Viewport.h

@@ -231,12 +231,12 @@ public:
     /** Returns a pointer to the scrollbar component being used.
         Handy if you need to customise the bar somehow.
     */
-    ScrollBar* getVerticalScrollBar() noexcept                  { return &verticalScrollBar; }
+    ScrollBar& getVerticalScrollBar() noexcept                  { return *verticalScrollBar; }
 
     /** Returns a pointer to the scrollbar component being used.
         Handy if you need to customise the bar somehow.
     */
-    ScrollBar* getHorizontalScrollBar() noexcept                { return &horizontalScrollBar; }
+    ScrollBar& getHorizontalScrollBar() noexcept                { return *horizontalScrollBar; }
 
     /** True if there's any off-screen content that could be scrolled vertically,
         or false if everything is currently visible.
@@ -277,9 +277,16 @@ public:
     /** @internal */
     static bool respondsToKey (const KeyPress&);
 
+protected:
+    //==============================================================================
+    /** Creates the Scrollbar components that will be used for that Viewport.
+        Subclasses can override this if they need to customise the scroolbars in some way.
+    */
+    virtual ScrollBar* createScrollBarComponent (bool isVertical);
+
 private:
     //==============================================================================
-    ScrollBar verticalScrollBar { true }, horizontalScrollBar { false };
+    ScopedPointer<ScrollBar> verticalScrollBar, horizontalScrollBar;
     Component contentHolder;
     WeakReference<Component> contentComp;
     Rectangle<int> lastVisibleArea;

modules/juce_gui_basics/widgets/juce_ListBox.cpp

@@ -791,16 +791,16 @@ void ListBox::mouseWheelMove (const MouseEvent& e, const MouseWheelDetails& whee
 {
     bool eventWasUsed = false;
 
-    if (wheel.deltaX != 0.0f && viewport->getHorizontalScrollBar()->isVisible())
+    if (wheel.deltaX != 0.0f && getHorizontalScrollBar().isVisible())
     {
         eventWasUsed = true;
-        viewport->getHorizontalScrollBar()->mouseWheelMove (e, wheel);
+        getHorizontalScrollBar().mouseWheelMove (e, wheel);
     }
 
-    if (wheel.deltaY != 0.0f && viewport->getVerticalScrollBar()->isVisible())
+    if (wheel.deltaY != 0.0f && getVerticalScrollBar().isVisible())
     {
         eventWasUsed = true;
-        viewport->getVerticalScrollBar()->mouseWheelMove (e, wheel);
+        getVerticalScrollBar().mouseWheelMove (e, wheel);
     }
 
     if (! eventWasUsed)
@@ -834,8 +834,8 @@ void ListBox::setMinimumContentWidth (const int newMinimumWidth)
 
 int ListBox::getVisibleContentWidth() const noexcept            { return viewport->getMaximumVisibleWidth(); }
 
-ScrollBar* ListBox::getVerticalScrollBar() const noexcept       { return viewport->getVerticalScrollBar(); }
-ScrollBar* ListBox::getHorizontalScrollBar() const noexcept     { return viewport->getHorizontalScrollBar(); }
+ScrollBar& ListBox::getVerticalScrollBar() const noexcept       { return viewport->getVerticalScrollBar(); }
+ScrollBar& ListBox::getHorizontalScrollBar() const noexcept     { return viewport->getHorizontalScrollBar(); }
 
 void ListBox::colourChanged()
 {

modules/juce_gui_basics/widgets/juce_ListBox.h

@@ -379,11 +379,11 @@ public:
     /** Scrolls if necessary to make sure that a particular row is visible. */
     void scrollToEnsureRowIsOnscreen (int row);
 
-    /** Returns a pointer to the vertical scrollbar. */
-    ScrollBar* getVerticalScrollBar() const noexcept;
+    /** Returns a reference to the vertical scrollbar. */
+    ScrollBar& getVerticalScrollBar() const noexcept;
 
-    /** Returns a pointer to the horizontal scrollbar. */
-    ScrollBar* getHorizontalScrollBar() const noexcept;
+    /** Returns a reference to the horizontal scrollbar. */
+    ScrollBar& getHorizontalScrollBar() const noexcept;
 
     /** Finds the row index that contains a given x,y position.
         The position is relative to the ListBox's top-left.

modules/juce_gui_basics/widgets/juce_TableListBox.cpp

@@ -357,20 +357,18 @@ Component* TableListBox::getCellComponent (int columnId, int rowNumber) const
 
 void TableListBox::scrollToEnsureColumnIsOnscreen (int columnId)
 {
-    if (auto* scrollbar = getHorizontalScrollBar())
-    {
-        auto pos = header->getColumnPosition (header->getIndexOfColumnId (columnId, true));
+    auto& scrollbar = getHorizontalScrollBar();
+    auto pos = header->getColumnPosition (header->getIndexOfColumnId (columnId, true));
 
-        auto x = scrollbar->getCurrentRangeStart();
-        auto w = scrollbar->getCurrentRangeSize();
+    auto x = scrollbar.getCurrentRangeStart();
+    auto w = scrollbar.getCurrentRangeSize();
 
-        if (pos.getX() < x)
-            x = pos.getX();
-        else if (pos.getRight() > x + w)
-            x += jmax (0.0, pos.getRight() - (x + w));
+    if (pos.getX() < x)
+        x = pos.getX();
+    else if (pos.getRight() > x + w)
+        x += jmax (0.0, pos.getRight() - (x + w));
 
-        scrollbar->setCurrentRangeStart (x);
-    }
+    scrollbar.setCurrentRangeStart (x);
 }
 
 int TableListBox::getNumRows()

modules/juce_gui_basics/widgets/juce_TextEditor.cpp

@@ -1869,8 +1869,7 @@ bool TextEditor::pageDown (bool selecting)
 
 void TextEditor::scrollByLines (int deltaLines)
 {
-    if (auto* scrollbar = viewport->getVerticalScrollBar())
-        scrollbar->moveScrollbarInSteps (deltaLines);
+    viewport->getVerticalScrollBar().moveScrollbarInSteps (deltaLines);
 }
 
 bool TextEditor::scrollDown()