From QTableWidget to QPainter

[hichemnho]

Hello,

I would like to fill a QTableWidget , and after clicking on the button to validate , paint lines between circles according to the condition that if the element[i][j] of the qtablewidget equals to 1 then there will be a line between the circle i and the circle j.
Here is the code:

//arbre.h
#ifndef ARBRE_H
#define ARBRE_H
#include <QtGui>
 
class Arbre :  public QWidget
{
Q_OBJECT
 
public:
Arbre();
 
private slots:
 
void dessin ();
private:
   QTableWidget* tableWidget;
   QPushButton * Tracer;
   QPainter *painter;
   int M [2][2];
//void paintEvent(QPaintEvent *);
};
 
 
 
#endif // ARBRE_H
 
//arbre.cpp
#include "arbre.h"
#include "math.h"
#include <QtGui>
Arbre::Arbre()
{
    tableWidget = new QTableWidget(2,2,this);
       Tracer = new QPushButton("Tracer",this);
       Tracer->move(10,10);
 
       connect(Tracer, SIGNAL(clicked()), this, SLOT(dessin()));
}
 
 
/*void Arbre::paintEvent(QPaintEvent *e)
{
   tableWidget = new QTableWidget(2,2,this);
   Tracer = new QPushButton("Tracer",this);
   Tracer->move(10,10);
 
   connect(Tracer, SIGNAL(clicked()), this, SLOT(dessin()));
}*/
/////////////////////////////////////////////////////////////////
 
 
 
void Arbre::dessin()
{
    int Nb_Sommet=2;
 
    int s;
    int k;
    QString str;
    for (s=0; s<Nb_Sommet; s++)
    {
      for (k=0; k<Nb_Sommet; k++)
      {
       M[s][k] = 0;
 
      }
    }
str = ((tableWidget->itemAt(1,0))->text());
    int dec = str.toInt();
    (M[0][1])=dec;
 QPainter painter(this);
 
 bool tour=false;
 int x=35;
 int y=45;
int Num_Sommet=0;
 
int T_Coordonnees [Nb_Sommet][Nb_Sommet];
while (Num_Sommet<Nb_Sommet)
{
 
     painter.drawEllipse(x,y,30,30);
     (T_Coordonnees[Num_Sommet][0])=x;
      (T_Coordonnees[Num_Sommet][1])=y;
 
 
    if (tour==false)
    {
        x+=85;
        tour=true;
    }
    else
    {
       y+=95;
       tour=false;
    }
Num_Sommet++;
}
Num_Sommet--;
int i,j;
for (i=0; i<Nb_Sommet; i++){
    for (j=0; j<Nb_Sommet; j++){
        if(  (M[i][j] == 1)&&(M[j][i]==1) )
        {
 
 
            painter.drawLine((T_Coordonnees[i][0]+20),(T_Coordonnees[i][1]),(T_Coordonnees[j][0]+20),(T_Coordonnees[j][1]));
            if(  (T_Coordonnees[i][1]>45)||(T_Coordonnees[j][1]>45)  )
            {
               painter.drawLine(((T_Coordonnees[i][0]+20)-10),(T_Coordonnees[i][1]),((T_Coordonnees[j][0]+20)-10),(T_Coordonnees[j][1]));
            }
            else
            {
            painter.drawLine((T_Coordonnees[i][0]+20),(T_Coordonnees[i][1]+30),(T_Coordonnees[j][0]+20),(T_Coordonnees[j][1]+30));
            }
        }
        else
        {
            if (M[i][j]==1)
            {
               painter.drawLine((T_Coordonnees[i][0]+20),(T_Coordonnees[i][1]),(T_Coordonnees[j][0]+20),(T_Coordonnees[j][1]));
            }
 
        }
 
    }
}
 
 
 
}
 
 
//main.cpp
 
#include <QApplication>
#include "arbre.h"
 
int main(int argc, char* argv[])
{
QApplication app(argc, argv);
 
Arbre fenetre;
fenetre.show();
 
return app.exec();
}

//arbre.h
#ifndef ARBRE_H
#define ARBRE_H
#include <QtGui>
 
class Arbre :  public QWidget
{
Q_OBJECT
 
public:
Arbre();
 
private slots:
 
void dessin ();
private:
   QTableWidget* tableWidget;
   QPushButton * Tracer;
   QPainter *painter;
   int M [2][2];
//void paintEvent(QPaintEvent *);
};
 
 
 
#endif // ARBRE_H
 
//arbre.cpp
#include "arbre.h"
#include "math.h"
#include <QtGui>
Arbre::Arbre()
{
    tableWidget = new QTableWidget(2,2,this);
       Tracer = new QPushButton("Tracer",this);
       Tracer->move(10,10);
 
       connect(Tracer, SIGNAL(clicked()), this, SLOT(dessin()));
}
 
 
/*void Arbre::paintEvent(QPaintEvent *e)
{
   tableWidget = new QTableWidget(2,2,this);
   Tracer = new QPushButton("Tracer",this);
   Tracer->move(10,10);
 
   connect(Tracer, SIGNAL(clicked()), this, SLOT(dessin()));
}*/
/////////////////////////////////////////////////////////////////
 
 
 
void Arbre::dessin()
{
    int Nb_Sommet=2;
 
    int s;
    int k;
    QString str;
    for (s=0; s<Nb_Sommet; s++)
    {
      for (k=0; k<Nb_Sommet; k++)
      {
       M[s][k] = 0;
 
      }
    }
str = ((tableWidget->itemAt(1,0))->text());
    int dec = str.toInt();
    (M[0][1])=dec;
 QPainter painter(this);
 
 bool tour=false;
 int x=35;
 int y=45;
int Num_Sommet=0;
 
int T_Coordonnees [Nb_Sommet][Nb_Sommet];
while (Num_Sommet<Nb_Sommet)
{
 
     painter.drawEllipse(x,y,30,30);
     (T_Coordonnees[Num_Sommet][0])=x;
      (T_Coordonnees[Num_Sommet][1])=y;
 
 
    if (tour==false)
    {
        x+=85;
        tour=true;
    }
    else
    {
       y+=95;
       tour=false;
    }
Num_Sommet++;
}
Num_Sommet--;
int i,j;
for (i=0; i<Nb_Sommet; i++){
    for (j=0; j<Nb_Sommet; j++){
        if(  (M[i][j] == 1)&&(M[j][i]==1) )
        {
 
 
            painter.drawLine((T_Coordonnees[i][0]+20),(T_Coordonnees[i][1]),(T_Coordonnees[j][0]+20),(T_Coordonnees[j][1]));
            if(  (T_Coordonnees[i][1]>45)||(T_Coordonnees[j][1]>45)  )
            {
               painter.drawLine(((T_Coordonnees[i][0]+20)-10),(T_Coordonnees[i][1]),((T_Coordonnees[j][0]+20)-10),(T_Coordonnees[j][1]));
            }
            else
            {
            painter.drawLine((T_Coordonnees[i][0]+20),(T_Coordonnees[i][1]+30),(T_Coordonnees[j][0]+20),(T_Coordonnees[j][1]+30));
            }
        }
        else
        {
            if (M[i][j]==1)
            {
               painter.drawLine((T_Coordonnees[i][0]+20),(T_Coordonnees[i][1]),(T_Coordonnees[j][0]+20),(T_Coordonnees[j][1]));
            }
 
        }
 
    }
}
 
 
 
}
 
 
//main.cpp
 
#include <QApplication>
#include "arbre.h"
 
int main(int argc, char* argv[])
{
QApplication app(argc, argv);
 
Arbre fenetre;
fenetre.show();
 
return app.exec();
}

To copy to clipboard, switch view to plain text mode 

Thank you in advance for your time and attention.

[wysota]

You can only paint from within a paintEvent(). Calculate your stuff, call update() (which will eventually call paintEvent()) and do the painting in the event handler.

[ChrisW67]

See the earlier thread for more on this same problem.