Add enabled state control to button and knob handlers

Signed-off-by: falkTX <falktx@falktx.com>

dgl/EventHandlers.hpp

@@ -1,6 +1,6 @@
 /*
  * DISTRHO Plugin Framework (DPF)
- * Copyright (C) 2012-2024 Filipe Coelho <falktx@falktx.com>
+ * Copyright (C) 2012-2025 Filipe Coelho <falktx@falktx.com>
  *
  * Permission to use, copy, modify, and/or distribute this software for any purpose with
  * or without fee is hereby granted, provided that the above copyright notice and this
@@ -63,6 +63,9 @@ public:
     bool isCheckable() const noexcept;
     void setCheckable(bool checkable) noexcept;
 
+    bool isEnabled() const noexcept;
+    void setEnabled(bool enabled) noexcept;
+
     Point<double> getLastClickPosition() const noexcept;
     Point<double> getLastMotionPosition() const noexcept;
 
@@ -121,6 +124,9 @@ public:
     KnobEventHandler& operator=(const KnobEventHandler& other);
     virtual ~KnobEventHandler();
 
+    bool isEnabled() const noexcept;
+    void setEnabled(bool enabled) noexcept;
+
     // if setStep(1) has been called before, this returns true
     bool isInteger() const noexcept;
 

dgl/src/EventHandlers.cpp

@@ -1,6 +1,6 @@
 /*
  * DISTRHO Plugin Framework (DPF)
- * Copyright (C) 2012-2024 Filipe Coelho <falktx@falktx.com>
+ * Copyright (C) 2012-2025 Filipe Coelho <falktx@falktx.com>
  *
  * Permission to use, copy, modify, and/or distribute this software for any purpose with
  * or without fee is hereby granted, provided that the above copyright notice and this
@@ -31,6 +31,7 @@ struct ButtonEventHandler::PrivateData {
     int state;
     bool checkable;
     bool checked;
+    bool enabled;
 
     Point<double> lastClickPos;
     Point<double> lastMotionPos;
@@ -44,11 +45,15 @@ struct ButtonEventHandler::PrivateData {
           state(kButtonStateDefault),
           checkable(false),
           checked(false),
+          enabled(true),
           lastClickPos(0, 0),
           lastMotionPos(0, 0)  {}
 
     bool mouseEvent(const Widget::MouseEvent& ev)
     {
+        if (! enabled)
+            return false;
+
         lastClickPos = ev.pos;
 
         // button was released, handle it now
@@ -98,6 +103,9 @@ struct ButtonEventHandler::PrivateData {
 
     bool motionEvent(const Widget::MotionEvent& ev)
     {
+        if (! enabled)
+            return false;
+
         // keep pressed
         if (button != -1)
         {
@@ -171,6 +179,24 @@ struct ButtonEventHandler::PrivateData {
         }
     }
 
+    void setEnabled(const bool enabled2) noexcept
+    {
+        if (enabled == enabled2)
+            return;
+
+        // reset temp vars if disabling
+        if (! enabled2)
+        {
+            button = -1;
+            state = kButtonStateDefault;
+            lastClickPos = Point<double>();
+            lastMotionPos = Point<double>();
+        }
+
+        enabled = enabled2;
+        widget->repaint();
+    }
+
     DISTRHO_DECLARE_NON_COPYABLE(PrivateData)
 };
 
@@ -217,6 +243,16 @@ void ButtonEventHandler::setCheckable(const bool checkable) noexcept
     pData->checkable = checkable;
 }
 
+bool ButtonEventHandler::isEnabled() const noexcept
+{
+    return pData->enabled;
+}
+
+void ButtonEventHandler::setEnabled(const bool enabled) noexcept
+{
+    pData->setEnabled(enabled);
+}
+
 Point<double> ButtonEventHandler::getLastClickPosition() const noexcept
 {
     return pData->lastClickPos;
@@ -281,6 +317,7 @@ struct KnobEventHandler::PrivateData {
     float value;
     float valueDef;
     float valueTmp;
+    bool enabled;
     bool usingDefault;
     bool usingLog;
     Orientation orientation;
@@ -301,6 +338,7 @@ struct KnobEventHandler::PrivateData {
           value(0.5f),
           valueDef(value),
           valueTmp(value),
+          enabled(true),
           usingDefault(false),
           usingLog(false),
           orientation(Vertical),
@@ -320,6 +358,7 @@ struct KnobEventHandler::PrivateData {
           value(other->value),
           valueDef(other->valueDef),
           valueTmp(value),
+          enabled(other->enabled),
           usingDefault(other->usingDefault),
           usingLog(other->usingLog),
           orientation(other->orientation),
@@ -338,6 +377,7 @@ struct KnobEventHandler::PrivateData {
         value        = other->value;
         valueDef     = other->valueDef;
         valueTmp     = value;
+        enabled      = other->enabled;
         usingDefault = other->usingDefault;
         usingLog     = other->usingLog;
         orientation  = other->orientation;
@@ -363,6 +403,9 @@ struct KnobEventHandler::PrivateData {
 
     bool mouseEvent(const Widget::MouseEvent& ev, const double scaleFactor)
     {
+        if (! enabled)
+            return false;
+
         if (ev.button != 1)
             return false;
 
@@ -416,6 +459,9 @@ struct KnobEventHandler::PrivateData {
 
     bool motionEvent(const Widget::MotionEvent& ev, const double scaleFactor)
     {
+        if (! enabled)
+            return false;
+
         if ((state & kKnobStateDragging) == 0x0)
             return false;
 
@@ -501,6 +547,9 @@ struct KnobEventHandler::PrivateData {
 
     bool scrollEvent(const Widget::ScrollEvent& ev)
     {
+        if (! enabled)
+            return false;
+
         if (! widget->contains(ev.pos))
             return false;
 
@@ -541,6 +590,25 @@ struct KnobEventHandler::PrivateData {
         return ((usingLog ? invlogscale(value) : value) - minimum) / diff;
     }
 
+    void setEnabled(const bool enabled2) noexcept
+    {
+        if (enabled == enabled2)
+            return;
+
+        // reset temp vars if disabling
+        if (! enabled2)
+        {
+            state = kKnobStateDefault;
+            lastX = 0.0;
+            lastY = 0.0;
+            lastClickTime = 0;
+            valueTmp = value;
+        }
+
+        enabled = enabled2;
+        widget->repaint();
+    }
+
     void setRange(const float min, const float max) noexcept
     {
         DISTRHO_SAFE_ASSERT_RETURN(max > min,);
@@ -598,6 +666,16 @@ KnobEventHandler::~KnobEventHandler()
     delete pData;
 }
 
+bool KnobEventHandler::isEnabled() const noexcept
+{
+    return pData->enabled;
+}
+
+void KnobEventHandler::setEnabled(const bool enabled) noexcept
+{
+    pData->setEnabled(enabled);
+}
+
 bool KnobEventHandler::isInteger() const noexcept
 {
     return d_isEqual(pData->step, 1.f);