Fixed paint and mouse event issues with QLineSeries

1. The bounding rectangle of QLineSeries item did not take line width
into account; this caused paint issues if the width is bigger than 1.
2. The width of the shape of the item was always 1. This caused
problems with mouse events; onClicked was not always signaled, even
if you click on top (but not in the middle of) a thick line series.

3 files changed, 16 insertions, 10 deletions

diff --git a/demos/chartinteractions/chart.cpp b/demos/chartinteractions/chart.cpp
index 986f5ae6..38c40643 100644
--- a/demos/chartinteractions/chart.cpp
+++ b/demos/chartinteractions/chart.cpp
@@ -20,6 +20,7 @@
 
 #include <QValuesAxis>
 #include <QAbstractAxis>
+#include <cmath>
 #include <QDebug>
 
 #include "chart.h"
@@ -36,22 +37,23 @@ Chart::~Chart()
 
 void Chart::clickPoint(const QPointF &point)
 {
-    //Get all points from the series.
-    QList<QPointF> points = m_series->points();
-    //Construct a small rectangle around the clicked point
-    //to identify the real point clicked from the series.
-    QRectF clickRect(point.x() - 0.5, point.y() - 0.5, 1.0, 1.0);
-
-    //Find the clicked point to be moved.
-    foreach (QPointF p, points) {
-        if (clickRect.contains(p)) {
+    // Find the closes data point
+    m_movingPoint = QPoint();
+    m_clicked = false;
+    foreach (QPointF p, m_series->points()) {
+        if (distance(p, point) < distance(m_movingPoint, point)) {
             m_movingPoint = p;
             m_clicked = true;
-            return;
         }
     }
 }
 
+qreal Chart::distance(const QPointF &p1, const QPointF &p2)
+{
+    return sqrt((p1.x() - p2.x()) * (p1.x() - p2.x())
+                + (p1.y() - p2.y()) * (p1.y() - p2.y()));
+}
+
 void Chart::setPointClicked(bool clicked)
 {
    m_clicked = clicked;
diff --git a/demos/chartinteractions/chart.h b/demos/chartinteractions/chart.h
index f9e021af..242aa65f 100644
--- a/demos/chartinteractions/chart.h
+++ b/demos/chartinteractions/chart.h
@@ -41,6 +41,7 @@ public:
     void setPointClicked(bool clicked);
 
 private:
+    qreal distance(const QPointF &p1, const QPointF &p2);
     QLineSeries *m_series;
     QPointF m_movingPoint;
 
diff --git a/demos/chartinteractions/main.cpp b/demos/chartinteractions/main.cpp
index 22ab027f..7b5db6c2 100644
--- a/demos/chartinteractions/main.cpp
+++ b/demos/chartinteractions/main.cpp
@@ -46,6 +46,9 @@ int main(int argc, char *argv[])
     Chart* chart = new Chart(0, 0, series);
     chart->legend()->hide();
     chart->addSeries(series);
+    QPen p = series->pen();
+    p.setWidth(5);
+    series->setPen(p);
     chart->createDefaultAxes();
     chart->setTitle("Drag'n drop to move data points");