edge color with k

edge.cpp

@@ -43,6 +43,12 @@ double Edge::getAngle() const
     return m_angle;
 }
 
+void Edge::setColor(const QColor &color)
+{
+    m_color = color;
+    update();
+}
+
 void Edge::adjust()
 {
     if (!m_sourceNode || !m_destNode)
@@ -95,7 +101,7 @@ void Edge::paint(QPainter *painter,
         return;
 
     // Draw the line itself
-    painter->setPen(QPen(Qt::black,
+    painter->setPen(QPen(m_color,
                          1,
                          Qt::SolidLine,
                          Qt::RoundCap,
@@ -113,7 +119,7 @@ void Edge::paint(QPainter *painter,
               QPointF(sin(m_angle - Edge::m_pi + Edge::m_pi / 3) * m_arrowSize,
                       cos(m_angle - Edge::m_pi + Edge::m_pi / 3) * m_arrowSize);
 
-    painter->setBrush(Qt::black);
+    painter->setBrush(m_color);
     painter->drawPolygon(QPolygonF() << line.p2()
                                      << destArrowP1
                                      << destArrowP2);

edge.h

@@ -15,6 +15,8 @@ public:
     Node *sourceNode() const;
     Node *destNode() const;
     double getAngle() const;
+    void setColor(const QColor &color);
+    QColor color() const { return m_color; }
 
     void adjust();
 
@@ -33,6 +35,7 @@ private:
     QPointF m_sourcePoint;
     QPointF m_destPoint;
     double m_angle;
+    QColor m_color;
 
     static const qreal m_arrowSize;
     static const double m_pi;

graphwidget.cpp

@@ -25,6 +25,7 @@ GraphWidget::GraphWidget(MainWindow *parent) :
     m_editingNode(false),
     m_edgeAdding(false),
     m_edgeDeleting(false),
+    m_edgeColoring(false),
     m_contentChanged(false)
 {
     m_scene = new QGraphicsScene(this);
@@ -104,9 +105,15 @@ void GraphWidget::readContentFromXmlFile(const QString &fileName)
         QDomElement e = edges.item(i).toElement();
         if(!e.isNull())
         {
-            m_scene->addItem(new Edge(
-                              m_nodeList[e.attribute("source").toInt()],
-                              m_nodeList[e.attribute("destination").toInt()]));
+            Edge *edge = new Edge(
+                        m_nodeList[e.attribute("source").toInt()],
+                        m_nodeList[e.attribute("destination").toInt()]);
+            edge->setColor(QColor(e.attribute("red").toFloat(),
+                                  e.attribute("green").toFloat(),
+                                  e.attribute("blue").toFloat(),
+                                  e.attribute("alpha").toFloat()));
+
+            m_scene->addItem(edge);
         }
     }
 
@@ -158,6 +165,11 @@ void GraphWidget::writeContentToXmlFile(const QString &fileName)
                       QString::number(m_nodeList.indexOf(edge->sourceNode())));
         cn.setAttribute( "destination",
                       QString::number(m_nodeList.indexOf(edge->destNode())));
+        cn.setAttribute( "red", QString::number(edge->color().red()));
+        cn.setAttribute( "green", QString::number(edge->color().green()));
+        cn.setAttribute( "blue", QString::number(edge->color().blue()));
+        cn.setAttribute( "alpha", QString::number(edge->color().alpha()));
+
         edges_root.appendChild(cn);
     }
 
@@ -220,6 +232,7 @@ void GraphWidget::keyPressEvent(QKeyEvent *event)
              event->key() == Qt::Key_D ||           // remove edge
              event->key() == Qt::Key_C ||           // node color
              event->key() == Qt::Key_T ||           // node text color
+             event->key() == Qt::Key_K ||           // edge text color
              ( event->modifiers() &  Qt::ControlModifier &&  // moving node
                ( event->key() == Qt::Key_Up ||
                  event->key() == Qt::Key_Down ||
@@ -247,6 +260,11 @@ void GraphWidget::keyPressEvent(QKeyEvent *event)
             m_edgeDeleting = false;
             m_parent->statusBarMsg(tr("Edge deleting cancelled."));
         }
+        else if (m_edgeColoring)
+        {
+            m_edgeColoring = false;
+            m_parent->statusBarMsg(tr("Edge coloring cancelled."));
+        }
         else if(m_showingNodeNumbers)
         {
             m_hintNumber.clear();
@@ -428,6 +446,14 @@ void GraphWidget::keyPressEvent(QKeyEvent *event)
 
         break;
     }
+
+    case Qt::Key_K:
+    {
+        m_parent->statusBarMsg(tr("Edge color: select other end-node."));
+        m_edgeColoring = true;
+        break;
+    }
+
     default:
         QGraphicsView::keyPressEvent(event);
     }
@@ -559,6 +585,21 @@ void GraphWidget::nodeSelected(Node *node)
         removeEdge(m_activeNode, node);
         m_edgeDeleting = false;
     }
+    else if (m_edgeColoring)
+    {
+        QColorDialog dialog(this);
+        dialog.setWindowTitle(tr("Select edge color"));
+        dialog.setOption(QColorDialog::ShowAlphaChannel);
+        if (dialog.exec())
+        {
+            QColor color = dialog.selectedColor();
+
+            Edge *edge = m_activeNode->edgeTo(node);
+            if (edge)
+                edge->setColor(color);
+        }
+        m_edgeColoring = false;
+    }
     else
     {
         setActiveNode(node);

graphwidget.h

@@ -61,6 +61,7 @@ private:
     bool m_editingNode;
     bool m_edgeAdding;
     bool m_edgeDeleting;
+    bool m_edgeColoring;
     bool m_contentChanged;
     QString m_fileName;
 

node.cpp

@@ -277,6 +277,16 @@ QList<Edge *> Node::edgesFrom() const
     return list;
 }
 
+Edge * Node::edgeTo(const Node *node) const
+{
+    foreach(EdgeElement element, m_edgeList)
+        if (element.edge->sourceNode() == node  ||
+            element.edge->destNode() == node)
+            return element.edge;
+
+    return 0;
+}
+
 void Node::paint(QPainter *painter,
                  const QStyleOptionGraphicsItem *option,
                  QWidget *w)

node.h

@@ -40,6 +40,7 @@ public:
     QPointF intersect(const QLineF &line, const bool &reverse = false) const;
 
     QList<Edge *> edgesFrom() const;
+    Edge * edgeTo(const Node* node) const;
 
 protected: