diff --git a/src/axis/qabstractaxis.cpp b/src/axis/qabstractaxis.cpp
index cb5ab69..ca38fec 100644
--- a/src/axis/qabstractaxis.cpp
+++ b/src/axis/qabstractaxis.cpp
@@ -544,15 +544,15 @@ void QAbstractAxis::hide()
 }
 
 
-void QAbstractAxis::setMin(const qreal min)
+void QAbstractAxis::setMin(const QVariant &min)
 {
     d_ptr->setMin(min);
 }
-void QAbstractAxis::setMax(const qreal max)
+void QAbstractAxis::setMax(const QVariant &max)
 {
     d_ptr->setMax(max);
 }
-void QAbstractAxis::setRange(const qreal min, const qreal max)
+void QAbstractAxis::setRange(const QVariant &min, const QVariant &max)
 {
     d_ptr->setRange(min,max);
 }
diff --git a/src/axis/qabstractaxis.h b/src/axis/qabstractaxis.h
index 56b07d6..55c4016 100644
--- a/src/axis/qabstractaxis.h
+++ b/src/axis/qabstractaxis.h
@@ -101,9 +101,9 @@ public:
     QColor shadesBorderColor() const;
 
     //range handling
-    void setMin(const qreal min);
-    void setMax(const qreal max);
-    void setRange(const qreal min, const qreal max);
+    void setMin(const QVariant &min);
+    void setMax(const QVariant &max);
+    void setRange(const QVariant &min, const QVariant &max);
 
     void show();
     void hide();
diff --git a/src/axis/qabstractaxis_p.h b/src/axis/qabstractaxis_p.h
index c51db87..33cf781 100644
--- a/src/axis/qabstractaxis_p.h
+++ b/src/axis/qabstractaxis_p.h
@@ -52,9 +52,9 @@ public:
     virtual void updateRange() = 0;
 
 protected:
-    virtual void setMin(const qreal min) = 0;
-    virtual void setMax(const qreal max) = 0;
-    virtual void setRange(const qreal min, const qreal max, bool force = false) = 0;
+    virtual void setMin(const QVariant &min) = 0;
+    virtual void setMax(const QVariant &max) = 0;
+    virtual void setRange(const QVariant &min, const QVariant &max, bool force = false) = 0;
     virtual int ticksCount() const = 0;
 
 public:
diff --git a/src/axis/qcategoriesaxis.cpp b/src/axis/qcategoriesaxis.cpp
index cff7386..57f7a7e 100644
--- a/src/axis/qcategoriesaxis.cpp
+++ b/src/axis/qcategoriesaxis.cpp
@@ -233,18 +233,23 @@ void QCategoriesAxisPrivate::setRangeCategory(const QString& minCategory, const 
     setRange(minIndex -0.5, maxIndex + 0.5);
 }
 
-void QCategoriesAxisPrivate::setMin(const qreal min)
+void QCategoriesAxisPrivate::setMin(const QVariant &min)
 {
     setRange(min,m_max);
 }
 
-void QCategoriesAxisPrivate::setMax(const qreal max)
+void QCategoriesAxisPrivate::setMax(const QVariant &max)
 {
     setRange(m_min,max);
 }
 
-void QCategoriesAxisPrivate::setRange(const qreal min, const qreal max, bool force)
+void QCategoriesAxisPrivate::setRange(const QVariant &min, const QVariant &max, bool force)
 {
+    Q_UNUSED(min);
+    Q_UNUSED(max);
+    Q_UNUSED(force);
+    // TODO: refactor
+/*
     if (max <= min) {
         // max must be greater than min
         return;
@@ -265,6 +270,7 @@ void QCategoriesAxisPrivate::setRange(const qreal min, const qreal max, bool for
         emit this->changed(m_min, m_max, qCeil(m_max) -qCeil(m_min) +1, false);
         emit q->categoriesChanged();
     }
+*/
 }
 
 int QCategoriesAxisPrivate::ticksCount() const
diff --git a/src/axis/qcategoriesaxis.h b/src/axis/qcategoriesaxis.h
index 87f9e98..7f99931 100644
--- a/src/axis/qcategoriesaxis.h
+++ b/src/axis/qcategoriesaxis.h
@@ -59,6 +59,10 @@ public:
     QString maxCategory() const;
     void setCategoryRange(const QString& minCategory, const QString& maxCategory);
 
+    void setMin(const QVariant &min);
+    void setMax(const QVariant &max);
+    void setRange(const QVariant &min, const QVariant &max);
+
 Q_SIGNALS:
     void categoriesChanged();
 
diff --git a/src/axis/qcategoriesaxis_p.h b/src/axis/qcategoriesaxis_p.h
index 5a4247c..c940b9f 100644
--- a/src/axis/qcategoriesaxis_p.h
+++ b/src/axis/qcategoriesaxis_p.h
@@ -53,9 +53,9 @@ private:
     void setRangeCategory(const QString& minCategory, const QString& maxCategory);
 
     //range handling
-    void setMin(const qreal min);
-    void setMax(const qreal max);
-    void setRange(const qreal min, const qreal max, bool force = false);
+    void setMin(const QVariant &min);
+    void setMax(const QVariant &max);
+    void setRange(const QVariant &min, const QVariant &max, bool force = false);
     int ticksCount() const;
 
 Q_SIGNALS:
diff --git a/src/axis/qvaluesaxis.cpp b/src/axis/qvaluesaxis.cpp
index 328b04c..24f656c 100644
--- a/src/axis/qvaluesaxis.cpp
+++ b/src/axis/qvaluesaxis.cpp
@@ -151,6 +151,23 @@ qreal QValuesAxis::max() const
 void QValuesAxis::setRange(qreal min, qreal max)
 {
     Q_D(QValuesAxis);
+    bool changed = false;
+    if (!qFuzzyIsNull(d->m_min - min)) {
+        d->m_min = min;
+        changed = true;
+        emit minChanged(min);
+    }
+
+    if (!qFuzzyIsNull(d->m_max - max)) {
+        d->m_max = max;
+        changed = true;
+        emit maxChanged(max);
+    }
+
+    if (changed) {
+       emit rangeChanged(d->m_min,d->m_max);
+       emit d->changed(d->m_min, d->m_max, d->m_ticksCount, d->m_niceNumbers);
+    }
     d->setRange(min,max);
 }
 
@@ -218,36 +235,31 @@ void QValuesAxisPrivate::handleAxisRangeChanged(qreal min, qreal max,int count)
 }
 
 
-void QValuesAxisPrivate::setMin(const qreal min)
+void QValuesAxisPrivate::setMin(const QVariant &min)
 {
-    setRange(min,m_max);
+    Q_Q(QValuesAxis);
+    bool ok;
+    qreal value = min.toReal(&ok);
+    if(ok) q->setMin(value);
 }
 
-void QValuesAxisPrivate::setMax(const qreal max)
+void QValuesAxisPrivate::setMax(const QVariant &max)
 {
-    setRange(m_min,max);
+    Q_Q(QValuesAxis);
+    bool ok;
+    qreal value = max.toReal(&ok);
+    if(ok) q->setMax(value);
 }
 
-void QValuesAxisPrivate::setRange(const qreal min, const qreal max, bool force)
+void QValuesAxisPrivate::setRange(const QVariant &min, const QVariant &max, bool force)
 {
+    Q_UNUSED(force);    // TODO: use this
     Q_Q(QValuesAxis);
-    bool changed = false;
-    if (!qFuzzyIsNull(m_min - min)) {
-        m_min = min;
-        changed = true;
-        emit q->minChanged(min);
-    }
-
-    if (!qFuzzyIsNull(m_max - max)) {
-        m_max = max;
-        changed = true;
-        emit q->maxChanged(max);
-    }
-
-    if ((changed) ||(force)) {
-       emit q->rangeChanged(m_min,m_max);
-       emit this->changed(m_min, m_max, m_ticksCount, m_niceNumbers);
-    }
+    bool ok1;
+    bool ok2;
+    qreal value1 = min.toReal(&ok1);
+    qreal value2 = max.toReal(&ok2);
+    if(ok1&&ok2) q->setRange(value1,value2);
 }
 
 int QValuesAxisPrivate::ticksCount() const
diff --git a/src/axis/qvaluesaxis_p.h b/src/axis/qvaluesaxis_p.h
index 6442d3f..9ffb1dd 100644
--- a/src/axis/qvaluesaxis_p.h
+++ b/src/axis/qvaluesaxis_p.h
@@ -53,9 +53,9 @@ public:
     void updateRange();
 
 protected:
-    void setMin(const qreal min);
-    void setMax(const qreal max);
-    void setRange(const qreal min, const qreal max, bool force = false);
+    void setMin(const QVariant &min);
+    void setMax(const QVariant &max);
+    void setRange(const QVariant &min, const QVariant &max, bool force = false);
     int ticksCount() const;
 
 private: