Fixed slider info displaying on right graph border

src/graphview.cpp

@@ -27,6 +27,9 @@ GraphView::GraphView(QWidget *parent)
 	_scene = new Scene(this);
 	setScene(_scene);
 
+	setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
+	setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
+
 	_xAxis = new AxisItem(AxisItem::X);
 	_yAxis = new AxisItem(AxisItem::Y);
 
@@ -148,9 +151,6 @@ void GraphView::loadData(const QVector<QPointF> &data)
 	pi->setPen(pen);
 	_scene->addItem(pi);
 	_graphs.append(pi);
-
-	if (_graphs.size() > 1)
-		_sliderInfo->hide();
 }
 
 void GraphView::redraw()
@@ -223,9 +223,7 @@ void GraphView::redraw(const QSizeF &size)
 	_slider->setPos(QPointF(sp * r.width(), r.bottom()));
 	_scene->addItem(_slider);
 
-	const QPainterPath &path = _graphs.at(0)->path();
-	QPointF p = path.pointAtPercent(sp);
-	_sliderInfo->setText(QString::number(-p.y() * _yScale, 'f', _precision));
+	_sliderInfo->setVisible(_graphs.size() == 1);
 
 	r = _scene->itemsBoundingRect();
 	_info->setPos(r.topLeft() + QPointF(r.width()/2
@@ -262,13 +260,10 @@ void GraphView::clear()
 		_scene->removeItem(_xAxis);
 	if (_yAxis->scene() == _scene)
 		_scene->removeItem(_yAxis);
-
 	if (_slider->scene() == _scene)
 		_scene->removeItem(_slider);
-
 	if (_info->scene() == _scene)
 		_scene->removeItem(_info);
-	_sliderInfo->show();
 
 	_slider->clear();
 	_info->clear();
@@ -320,7 +315,7 @@ void GraphView::emitSliderPositionChanged(const QPointF &pos)
 	qreal val = pos.x() / _slider->area().width();
 	emit sliderPositionChanged(val * _bounds.width());
 
-	if (!_sliderInfo->isVisible())
+	if (_graphs.size() > 1)
 		return;
 
 	const QPainterPath &path = _graphs.at(0)->path();
@@ -331,6 +326,11 @@ void GraphView::emitSliderPositionChanged(const QPointF &pos)
 
 	qreal y = yAtX(path, val * _bounds.width());
 	qreal r = (y - br.bottom()) / br.height();
+
+	SliderInfoItem::Side s = (pos.x() + _sliderInfo->boundingRect().width()
+	  > _slider->area().right()) ? SliderInfoItem::Left : SliderInfoItem::Right;
+
+	_sliderInfo->setSide(s);
 	_sliderInfo->setPos(QPointF(0, _slider->boundingRect().height() * r));
 	_sliderInfo->setText(QString::number(-y * _yScale, 'f', _precision));
 }

src/sliderinfoitem.cpp

@@ -7,6 +7,7 @@
 
 SliderInfoItem::SliderInfoItem(QGraphicsItem *parent) : QGraphicsItem(parent)
 {
+	_side = Right;
 }
 
 void SliderInfoItem::updateBoundingRect()
@@ -16,7 +17,10 @@ void SliderInfoItem::updateBoundingRect()
 	font.setFamily(FONT_FAMILY);
 	QFontMetrics fm(font);
 
-	_boundingRect = QRectF(-SIZE/2, 0, fm.width(_text) + SIZE, fm.height());
+	_boundingRect = (_side == Right)
+		? QRectF(-SIZE/2, 0, fm.width(_text) + SIZE, fm.height())
+		: QRectF(-(fm.width(_text) + SIZE/2), 0, fm.width(_text) + SIZE,
+		  fm.height());
 }
 
 void SliderInfoItem::paint(QPainter *painter, const QStyleOptionGraphicsItem
@@ -31,7 +35,11 @@ void SliderInfoItem::paint(QPainter *painter, const QStyleOptionGraphicsItem
 	painter->setFont(font);
 
 	painter->setPen(Qt::red);
+	if (_side == Right)
 		painter->drawText(SIZE, fm.height() - fm.descent(), _text);
+	else
+		painter->drawText(-(fm.width(_text) + SIZE/2),
+		  fm.height() - fm.descent(), _text);
 	painter->drawLine(QPointF(-SIZE/2, 0), QPointF(SIZE/2, 0));
 
 	//painter->drawRect(boundingRect());
@@ -43,3 +51,13 @@ void SliderInfoItem::setText(const QString &text)
 	updateBoundingRect();
 	prepareGeometryChange();
 }
+
+void SliderInfoItem::setSide(Side side)
+{
+	if (side == _side)
+		return;
+
+	_side = side;
+	updateBoundingRect();
+	prepareGeometryChange();
+}

src/sliderinfoitem.h

@@ -6,6 +6,8 @@
 class SliderInfoItem : public QGraphicsItem
 {
 public:
+	enum Side {Left, Right};
+
 	SliderInfoItem(QGraphicsItem *parent = 0);
 
 	QRectF boundingRect() const {return _boundingRect;}
@@ -13,10 +15,12 @@ public:
 	  QWidget *widget);
 
 	void setText(const QString &text);
+	void setSide(Side side);
 
 private:
 	void updateBoundingRect();
 
+	Side _side;
 	QString _text;
 	QRectF _boundingRect;
 };