fix: wheel event not propagating to parent in Qt6

include/widgets/dcombobox.h

@@ -23,6 +23,8 @@ class LIBDTKWIDGETSHARED_EXPORT DComboBox : public QComboBox, public DCORE_NAMES
 protected:
     DComboBox(DComboBoxPrivate &dd, QWidget *parent);
 
+    void wheelEvent(QWheelEvent *event) override;
+
     // QComboBox interface
 public:
     virtual void showPopup() override;

include/widgets/dspinbox.h

@@ -25,6 +25,10 @@ class LIBDTKWIDGETSHARED_EXPORT DSpinBox : public QSpinBox, public DTK_CORE_NAME
 public:
     explicit DSpinBox(QWidget *parent = nullptr);
 
+protected:
+    void wheelEvent(QWheelEvent *event) override;
+
+public:
     QLineEdit *lineEdit() const;
 
     bool isAlert() const;
@@ -65,6 +69,10 @@ class LIBDTKWIDGETSHARED_EXPORT DDoubleSpinBox : public QDoubleSpinBox, public D
 public:
     explicit DDoubleSpinBox(QWidget *parent = nullptr);
 
+protected:
+    void wheelEvent(QWheelEvent *event) override;
+
+public:
     bool isAlert() const;
     void showAlertMessage(const QString &text, int duration = 3000);
     void showAlertMessage(const QString &text, QWidget *follower, int duration = 3000);

src/widgets/dcombobox.cpp

@@ -29,9 +29,10 @@
 #include <QScrollBar>
 #include <QHeaderView>
 #include <QCursor>
 #include <QScreen>
 #include <QStack>
 #include <QWindow>
+#include <QWheelEvent>
 
 DWIDGET_BEGIN_NAMESPACE
 
@@ -119,6 +120,15 @@
     d->init();
 }
 
+void DComboBox::wheelEvent(QWheelEvent *event)
+{
+    if (hasFocus()) {
+        QComboBox::wheelEvent(event);
+    } else {
+        QWidget::wheelEvent(event);
+    }
+}
+
 /*!
  * @~english 
     @brief Override QComboBox::showPopup to limit the maximum display height according to maxVisibleItems(), which has a default value of 16. The maximum display height can be changed using setMaxVisibleItems(), which makes the setMaximumHeight() interface ineffective.

src/widgets/dslider.cpp

@@ -136,7 +136,11 @@ bool DSlider::eventFilter(QObject *watched, QEvent *e)
     Q_D(DSlider);
 
     if ((watched == d->slider) && (e->type() == QEvent::Wheel)) {
-        return !d->mouseWheelEnabled;
+        if (d->mouseWheelEnabled && d->slider->hasFocus()) {
+            return false;  // let QSlider::wheelEvent handle it (stepBy + accept)
+        }
+        e->ignore();  // Qt6: un-accept so event propagates to parent (e.g. scrollarea)
+        return true;   // block delivery to the inner QSlider
     }
 
     if (e->type() == QEvent::MouseButtonRelease) {

src/widgets/dspinbox.cpp

@@ -6,8 +6,10 @@
 
 #include "dspinbox.h"
 #include "private/dspinbox_p.h"
 #include "dlineedit.h"
 
+#include <QWheelEvent>
+
 DWIDGET_BEGIN_NAMESPACE
 
 DSpinBoxPrivate::DSpinBoxPrivate(DSpinBox *parent) :
@@ -65,6 +67,15 @@
     d_func()->init();
 }
 
+void DSpinBox::wheelEvent(QWheelEvent *event)
+{
+    if (hasFocus()) {
+        QSpinBox::wheelEvent(event);
+    } else {
+        QWidget::wheelEvent(event);
+    }
+}
+
 /*!
 @~english
   @brief get the input line widget
@@ -182,6 +193,15 @@
     d_func()->init();
 }
 
+void DDoubleSpinBox::wheelEvent(QWheelEvent *event)
+{
+    if (hasFocus()) {
+        QDoubleSpinBox::wheelEvent(event);
+    } else {
+        QWidget::wheelEvent(event);
+    }
+}
+
 bool DDoubleSpinBox::isAlert() const
 {
     D_DC(DDoubleSpinBox);