From Forum Nokia Wiki

ID	...	Creation date	23 June 2009
Platform	S60 3rd Edition FP2, S60 5th Edition	Tested on devices	S60 Emulator
Category	Qt for S60	Subcategory	Application

Keywords (APIs, classes, methods, functions): QGraphicsScene,QGraphicsView

Overview

This code will show you the line drawing in the QGraphicsScene by getting the end points of line with the help of mouseMove() Event.

When the mouse is moved on the widget at that time the mouse coordinates are catched and use to draw line from center to that specific coordinate.

Preconditions

• Download and Install latest version Qt for Symbian - Installation packages which has links on how to install the latest version

Source Code

Source.h

#ifndef EVE1_H
#define EVE1_H
 
#include <QtGui/QWidget>
#include<QMouseEvent>
#include<QGraphicsLineItem>
#include<QGraphicsScene>
#include<QGraphicsView>
#include<QGraphicsItem>
#include<QHBoxLayout>
class EVE1 : public QWidget
{
    Q_OBJECT
 
public:
    EVE1(QWidget *parent = 0);
    ~EVE1();
 
private:
    QHBoxLayout *lay;
    QGraphicsScene *scene;
     QGraphicsItem *item;
     QGraphicsView *view;
private slots:
    void mouseMoveEvent(QMouseEvent *);
};
 
#endif // EVE1_H

Source.cpp

#include "eve1.h"
#include "ui_eve1.h"
 
EVE1::EVE1(QWidget *parent)
    : QWidget(parent)
{
     lay=new QHBoxLayout(this);
    scene=new QGraphicsScene(this);
    scene->setSceneRect(0,0,250,250);
    view=new QGraphicsView(scene,this);
    view->show();
    setMouseTracking(1);//Enable Mouse tracking on widget.
    lay->addWidget(view);
    setLayout(lay);
 
}
 
EVE1::~EVE1()
{
     // No need to delete any object that has got a parent which is properly deleted.
}
void EVE1::mouseMoveEvent(QMouseEvent *event)
{
    int X=event->x();
    int Y=event->y();
    int Z=scene->height()/2;
    int W=scene->width()/2;
    scene->addLine(Z,W,X,Y);
 
}

ScreenShot

NOTE:MOVE YOUR MOUSE ARROUND THE WIDGET NOT ON THE WIDGET....