Disable combobox scroll hijacking, and only show one event by default (rather than all)

noscrollspinbox.cpp

@@ -0,0 +1,16 @@
+#include "noscrollspinbox.h"
+
+NoScrollSpinBox::NoScrollSpinBox(QWidget *parent)
+    : QSpinBox(parent)
+{
+    // Don't let scrolling hijack focus.
+    setFocusPolicy(Qt::StrongFocus);
+}
+
+void NoScrollSpinBox::wheelEvent(QWheelEvent *event)
+{
+    // Only allow scrolling to modify contents when it explicitly has focus.
+    if (hasFocus())
+        QSpinBox::wheelEvent(event);
+}
+