Getting a pointer out of on_pushButton_clicked()

[reis2211]

I'm having a problem with getting inputs out of on_pushButton_clicked().
My program reads a file and gets the data into a structure, which is created inside the function on_pushButton_clicked().
Then I want to get that structure out of on_pushButton_clicked() to use it in future functions. How can I do it? (I want to get the "topo" pointer out, without needing to call the function on_pushButton_clicked() )
Here is my code:
Thank you in advance.

Mainwindow.cpp:

#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QFile>
#include <QFileDialog>
#include "Estrutura.h"
#include <QString>
#include <QTextStream>
#include <QMessageBox>

MainWindow::MainWindow(QWidget *parent)
: QMainWindow(parent)
, ui(new Ui::MainWindow)
{
ui->setupUi(this);
}

MainWindow::~MainWindow()
{
delete ui;
}

void MainWindow::on_pushButton_clicked()
{
QString linha;
QStringList list;
float tempo,velocidade,pack1,pack2,pack3,cellT;
header topo;

QFile file(QFileDialog::getOpenFileName(this,tr("Open File"),"",tr("Text Files (*.txt)"))); 

if(!file.open(QIODevice::ReadOnly))                    
    QMessageBox::information(0,"info",file.errorString());

topo=inicializalista(); 



QTextStream in(&file);

while(!in.atEnd())
{

   linha=in.readLine(); 

   list=linha.split(" ");

   tempo=list[0].toFloat();
   velocidade=list[1].toFloat();
   pack1=list[2].toFloat();
   pack2=list[3].toFloat();
   pack3=list[4].toFloat();
   cellT=list[5].toFloat();

   topo=inserelista(topo,tempo,velocidade,pack1,pack2,pack3,cellT); 

}
imprimelista(topo);

}

lista.cpp:

#include "Estrutura.h"
#include <stdlib.h>
#include <QDebug>

header inicializalista(){

header novo;

novo=(header)calloc(1,sizeof(dados));//alocação de memória

novo->cellT=0;                  //inicialização de todas as variáveis
novo->pack1=0;
novo->pack2=0;
novo->pack3=0;
novo->tempo=0;
novo->velocidade=0;
novo->next=nullptr;

return novo;

}

header inserelista(header topo,float tempo,float velocidade,float pack1,float pack2,float pack3,float cellT){

if( (topo->cellT==0.0) && (topo->pack1==0.0) && (topo->pack2==0.0) && (topo->pack3==0.0) && (topo->velocidade==0.0) && (topo->tempo==0.0))
{
      topo->cellT=cellT;            //caso a lista esteja vazia faz-se a substituição de valores
      topo->pack1=pack1;
      topo->pack2=pack2;
      topo->pack3=pack3;
      topo->tempo=tempo;
      topo->velocidade=velocidade;
}
else
{
    header novo;                         //inserção de um novo bloco no fim da lista
    header aux;
    novo=(header)calloc(1,sizeof(dados));

    for(aux=topo;aux->next!=nullptr;aux=aux->next);

    aux->next=novo;
    novo->next=nullptr;
    novo->cellT=cellT;
    novo->pack1=pack1;
    novo->pack2=pack2;
    novo->pack3=pack3;
    novo->tempo=tempo;
    novo->velocidade=velocidade;

}

return topo;

}

void imprimelista(header topo)
{
header aux;

for(aux=topo;aux!=nullptr;aux=aux->next)    //impressão da lista na consola para efeitos de verificação
{
    qDebug()<< "tempo" << aux->tempo;
    qDebug()<< "velocidade" << aux->velocidade;
    qDebug()<< "pack1" << aux->pack1;
    qDebug()<< "pack2" << aux->pack2 ;
    qDebug()<< "pack3" << aux->pack3;
    qDebug()<< "cellT" << aux->cellT<<"\n";


}

}

Estrutura.h:

#ifndef ESTRUTURA_H
#define ESTRUTURA_H

class dados{

public:
float tempo;
float velocidade;
float pack1;
float pack2;
float pack3;
float cellT;

dados* next;

};

typedef dados* header;

header inicializalista();
header inserelista(header topo,float tempo,float velocidade,float pack1,float pack2,float pack3,float cellT);
void imprimelista(header topo);

#endif // ESTRUTURA_H

[jsulm]

@reis2211 said in Getting a pointer out of on_pushButton_clicked():

How can I do it?

Make topo member variable of your class...

[reis2211]

@jsulm said in Getting a pointer out of on_pushButton_clicked():

member variable of your class.

Could you explain, more precisely, how that would help me getting "topo" out of on_pushButton_clicked, i'm a bit confused...
Thank you, again, in advance.

[jsulm]

@reis2211 If topo is member variable it can be accessed everywhere in that class like any other member variable.

class MainWindow...
private:
    header topo; // Can be accessed everywhere in MainWindow

Or do you want to access it outside of MainWindow?
In that case you cann add a getter method:

class MainWindow...
public:
    header getTopo()
    {
        return topo;
    }
private:
    header topo; // Can be accessed everywhere in MainWindow

[reis2211]

@jsulm Thank you so much for you help!
Greetings!