Index: /trunk/FACT++/gui/SpinBox4ns.h
===================================================================
--- /trunk/FACT++/gui/SpinBox4ns.h	(revision 10455)
+++ /trunk/FACT++/gui/SpinBox4ns.h	(revision 10455)
@@ -0,0 +1,32 @@
+#include <QtGui/QSpinBox>
+
+class SpinBox4ns : public QSpinBox
+{
+public:
+    SpinBox4ns(QWidget *p) : QSpinBox(p)
+    {
+    }
+
+    QValidator::State validate (QString &input, int &p) const
+    {
+        const QValidator::State rc = QSpinBox::validate(input, p);
+        if (rc!=QValidator::Acceptable)
+            return rc;
+
+        const int pf = prefix().length();
+        const int sf = suffix().length();
+        const int len = input.length();
+
+        return input.mid(pf, len-sf-pf).toUInt()%4==0 ? QValidator::Acceptable : QValidator::Intermediate;
+    }
+
+    void fixup(QString &input) const
+    {
+        const int pf = prefix().length();
+        const int sf = suffix().length();
+        const int len = input.length();
+
+        const uint i = input.mid(pf, len-pf-sf).toUInt()+2;
+        input = QString::number((i/4)*4);
+    }
+};