made slider value/string conversions abstract

app/widget/slider/floatslider.cpp

@@ -32,6 +32,8 @@ FloatSlider::FloatSlider(QWidget *parent) :
   decimal_places_(1),
   autotrim_decimal_places_(false)
 {
+  SetValue(0.0);
+
   connect(this, SIGNAL(ValueChanged(QVariant)), this, SLOT(ConvertValue(QVariant)));
 }
 

app/widget/slider/integerslider.cpp

@@ -25,6 +25,8 @@ namespace olive {
 IntegerSlider::IntegerSlider(QWidget* parent) :
   SliderBase(kInteger, parent)
 {
+  SetValue(0);
+
   connect(this, SIGNAL(ValueChanged(QVariant)), this, SLOT(ConvertValue(QVariant)));
 }
 

app/widget/slider/sliderbase.cpp

@@ -62,12 +62,10 @@ SliderBase::SliderBase(Mode mode, QWidget *parent) :
   switch (mode_) {
   case kString:
     setCursor(Qt::PointingHandCursor);
-    SetValue(QString());
     break;
   case kInteger:
   case kFloat:
     setCursor(Qt::SizeHorCursor);
-    SetValue(0);
     break;
   }
 }

app/widget/slider/sliderbase.h

@@ -84,9 +84,9 @@ protected:
 
   virtual double AdjustDragDistanceInternal(const double& start, const double& drag);
 
-  virtual QString ValueToString(const QVariant &v);
+  virtual QString ValueToString(const QVariant &v) = 0;
 
-  virtual QVariant StringToValue(const QString& s, bool* ok);
+  virtual QVariant StringToValue(const QString& s, bool* ok) = 0;
 
   virtual void changeEvent(QEvent* e) override;
 

app/widget/slider/stringslider.cpp

@@ -25,6 +25,8 @@ namespace olive {
 StringSlider::StringSlider(QWidget* parent) :
   SliderBase(kString, parent)
 {
+  SetValue(QString());
+
   connect(this, SIGNAL(ValueChanged(QVariant)), this, SLOT(ConvertValue(QVariant)));
 }
 

app/widget/slider/timeslider.cpp

@@ -29,6 +29,7 @@ TimeSlider::TimeSlider(QWidget *parent) :
   IntegerSlider(parent)
 {
   SetMinimum(0);
+  SetValue(0);
 
   connect(Core::instance(), &Core::TimecodeDisplayChanged, this, &TimeSlider::TimecodeDisplayChanged);
 }