Slider: Add keyboard control even without accessibility

modules/juce_gui_basics/native/accessibility/juce_win32_Accessibility.cpp

@@ -206,10 +206,14 @@ void AccessibilityHandler::notifyAccessibilityEvent (AccessibilityEvent eventTyp
     {
         if (auto* valueInterface = getValueInterface())
         {
-            VARIANT newValue;
-            VariantHelpers::setString (valueInterface->getCurrentValueAsString(), &newValue);
+            const auto propertyType = getRole() == AccessibilityRole::slider ? UIA_RangeValueValuePropertyId
+                                                                             : UIA_ValueValuePropertyId;
 
-            sendAccessibilityPropertyChangedEvent (*this, UIA_ValueValuePropertyId, newValue);
+            const auto value = getRole() == AccessibilityRole::slider
+                               ? VariantHelpers::getWithValue (valueInterface->getCurrentValue())
+                               : VariantHelpers::getWithValue (valueInterface->getCurrentValueAsString());
+
+            sendAccessibilityPropertyChangedEvent (*this, propertyType, value);
         }
 
         return;

modules/juce_gui_basics/native/accessibility/juce_win32_UIAHelpers.h

@@ -28,6 +28,17 @@ namespace juce
 
 namespace VariantHelpers
 {
+    namespace Detail
+    {
+        template <typename Fn, typename ValueType>
+        inline VARIANT getWithValueGeneric (Fn&& setter, ValueType value)
+        {
+            VARIANT result{};
+            setter (value, &result);
+            return result;
+        }
+    }
+
     inline void clear (VARIANT* variant)
     {
         variant->vt = VT_EMPTY;
@@ -56,6 +67,9 @@ namespace VariantHelpers
         variant->vt     = VT_R8;
         variant->dblVal = value;
     }
+
+    inline VARIANT getWithValue (double value)        { return Detail::getWithValueGeneric (&setDouble, value); }
+    inline VARIANT getWithValue (const String& value) { return Detail::getWithValueGeneric (&setString, value); }
 }
 
 inline JUCE_COMRESULT addHandlersToArray (const std::vector<const AccessibilityHandler*>& handlers, SAFEARRAY** pRetVal)

modules/juce_gui_basics/widgets/juce_Slider.cpp

@@ -26,6 +26,14 @@
 namespace juce
 {
 
+static double getStepSize (const Slider& slider)
+{
+    const auto interval = slider.getInterval();
+
+    return interval != 0.0 ? interval
+                           : slider.getRange().getLength() * 0.01;
+}
+
 class Slider::Pimpl   : public AsyncUpdater, // this needs to be public otherwise it will cause an
                                              // error when JUCE_DLL_BUILD=1
                         private Value::Listener
@@ -991,6 +999,38 @@ public:
         popupDisplay.reset();
     }
 
+    bool keyPressed (const KeyPress& key)
+    {
+        if (key.getModifiers().isAnyModifierKeyDown())
+            return false;
+
+        const auto getInterval = [this]
+        {
+            if (auto* accessibility = owner.getAccessibilityHandler())
+                if (auto* valueInterface = accessibility->getValueInterface())
+                    return valueInterface->getRange().getInterval();
+
+            return getStepSize (owner);
+        };
+
+        const auto valueChange = [&]
+        {
+            if (key == KeyPress::rightKey || key == KeyPress::upKey)
+                return getInterval();
+
+            if (key == KeyPress::leftKey || key == KeyPress::downKey)
+                return -getInterval();
+
+            return 0.0;
+        }();
+
+        if (valueChange == 0.0)
+            return false;
+
+        setValue (getValue() + valueChange, sendNotificationSync);
+        return true;
+    }
+
     void showPopupDisplay()
     {
         if (style == IncDecButtons)
@@ -1661,6 +1701,9 @@ void Slider::mouseExit (const MouseEvent&)      { pimpl->mouseExit(); }
 // it is shown when dragging the mouse over a slider and releasing
 void Slider::mouseEnter (const MouseEvent&)     { pimpl->mouseMove(); }
 
+/** @internal */
+bool Slider::keyPressed (const KeyPress& k)     { return pimpl->keyPressed (k); }
+
 void Slider::modifierKeysChanged (const ModifierKeys& modifiers)
 {
     if (isEnabled())
@@ -1734,18 +1777,10 @@ private:
         AccessibleValueRange getRange() const override
         {
             return { { slider.getMinimum(), slider.getMaximum() },
-                     getStepSize() };
+                     getStepSize (slider) };
         }
 
     private:
-        double getStepSize() const
-        {
-            auto interval = slider.getInterval();
-
-            return interval != 0.0 ? interval
-                                   : slider.getRange().getLength() * 0.01;
-        }
-
         Slider& slider;
         const bool useMaxValue;
 

modules/juce_gui_basics/widgets/juce_Slider.h

@@ -991,6 +991,8 @@ public:
     void mouseExit (const MouseEvent&) override;
     /** @internal */
     void mouseEnter (const MouseEvent&) override;
+    /** @internal */
+    bool keyPressed (const KeyPress&) override;
 
     //==============================================================================
    #ifndef DOXYGEN