ui: graph view edges

Added simple edges to the graph view. Also fixed a memory leak source in QtMainWindow.

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src/app/qt/view/graphElements/QtGraphEdge.cpp

@@ -0,0 +1,59 @@
+#include "qt/view/graphElements/QtGraphEdge.h"
+
+#include "qpen.h"
+
+#include "component/view/graphElements/GraphNode.h"
+
+QtGraphEdge::QtGraphEdge(const std::weak_ptr<GraphNode>& owner, const std::weak_ptr<GraphNode>& target)
+	: m_owner(owner)
+	, m_target(target)
+{
+	std::shared_ptr<GraphNode> o = owner.lock();
+	std::shared_ptr<GraphNode> t = target.lock();
+
+	if (o != NULL && t != NULL)
+	{
+		this->setLine(o->getPosition().x, o->getPosition().y,t->getPosition().x, t->getPosition().y);
+	}
+	else
+	{
+		LOG_WARNING("Either the owner or the target node could is null.");
+	}
+
+	QPen blackPen(Qt::black);
+    blackPen.setWidth(3);
+
+	this->setPen(blackPen);
+}
+
+QtGraphEdge::~QtGraphEdge()
+{
+}
+
+void QtGraphEdge::ownerMoved()
+{
+	std::shared_ptr<GraphNode> node = m_owner.lock();
+
+	if (node != NULL)
+	{
+		this->setLine(node->getPosition().x, node->getPosition().y, this->line().x2(), this->line().y2());
+	}
+	else
+	{
+		LOG_WARNING("Owner node is null.");
+	}
+}
+
+void QtGraphEdge::targetMoved()
+{
+	std::shared_ptr<GraphNode> node = m_target.lock();
+
+	if (node != NULL)
+	{
+		this->setLine(this->line().x1(), this->line().y1(), node->getPosition().x, node->getPosition().y);
+	}
+	else
+	{
+		LOG_WARNING("Target node is null.");
+	}
+}