Passing variable from one form to another

[Nicklax]

Hello, I am having trouble passing a value from one function in Qt to another in a different form

Beastiary.cpp

void beastiary::on_listWidget_itemClicked(QListWidgetItem *item)
{   
   const QString nvalue = ui->listWidget->currentItem()->text(); //Value that needs to passed
   read red;
   red.setModal(true);
   red.exec();
   red.ulk();
 
}

void beastiary::on_listWidget_itemClicked(QListWidgetItem *item)
{   
   const QString nvalue = ui->listWidget->currentItem()->text(); //Value that needs to passed
   read red;
   red.setModal(true);
   red.exec();
   red.ulk();

}

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read.cpp

void read::ulk()
{
 
    QFile file (nvalue); //needs nvalue from beastiary so it knows the name of the file to look for
    if (!file.open(QFile::ReadOnly | QFile::Text))
     {
         QMessageBox::warning (this, "Error", "File Could not Be Opened");
 
     }
  QString line;
  QTextStream in(&file);
  while (!in.atEnd())
   {
    line = in.readLine();
    ui->lineEdit_name_r->setText(ui->lineEdit_name_r->text()+line);
    qDebug() <<line;
   }
}

void read::ulk()
{

    QFile file (nvalue); //needs nvalue from beastiary so it knows the name of the file to look for
    if (!file.open(QFile::ReadOnly | QFile::Text))
     {
         QMessageBox::warning (this, "Error", "File Could not Be Opened");

     }
  QString line;
  QTextStream in(&file);
  while (!in.atEnd())
   {
    line = in.readLine();
    ui->lineEdit_name_r->setText(ui->lineEdit_name_r->text()+line);
    qDebug() <<line;
   }
}

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The variable nvalue must be obtained in beastiary.cpp but is needed in read.cpp and im not sure of how to pass the variable to read from beastiary.

[monillo]

Hi.
In read.cpp or read.h add variable nvalue (if you like the same name), now in beastiary.cpp before red.exe() assign value to "nvalue", for example: red.nvalue = nvalue.

Hope this help.

[Nicklax]

Thanks for the reply, I tried your suggestion but got the following error: passing 'const QString' as 'this' argument discards qualifiers [-fpermissive]

This is the code I wrote for it
read.h

#ifndef READ_H
#define READ_H
 
#include <QDialog>
 
 
namespace Ui {
class read;
}
 
class read : public QDialog
{
    Q_OBJECT
 
friend class beastiary;
 
public:
     const QString nvalue;
     void ulk();
     explicit read(QWidget *parent = 0);
       ~read();
 
private:
     Ui::read *ui;
 
};
 
 
#endif // READ_H

#ifndef READ_H
#define READ_H

#include <QDialog>


namespace Ui {
class read;
}

class read : public QDialog
{
    Q_OBJECT

friend class beastiary;

public:
     const QString nvalue;
     void ulk();
     explicit read(QWidget *parent = 0);
       ~read();

private:
     Ui::read *ui;

};


#endif // READ_H

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beastiary.cpp

void beastiary::on_listWidget_itemClicked(QListWidgetItem *item)
{
   const QString nvalue  = ui->listWidget->currentItem()->text();
   read red;
   red.nvalue=nvalue;
   red.setModal(true);
   red.exec();
   red.ulk();
 
}

void beastiary::on_listWidget_itemClicked(QListWidgetItem *item)
{
   const QString nvalue  = ui->listWidget->currentItem()->text();
   read red;
   red.nvalue=nvalue;
   red.setModal(true);
   red.exec();
   red.ulk();

}

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read.cpp

void read::ulk()
{
    QFile file (nvalue);
    if (!file.open(QFile::ReadOnly | QFile::Text))
     {
         QMessageBox::warning (this, "Error", "File Could not Be Opened");
     }
  QString line;
  QTextStream in(&file);
  while (!in.atEnd())
   {
    line = in.readLine();
    ui->lineEdit_name_r->setText(ui->lineEdit_name_r->text()+line);
    qDebug() <<line;
   }
}

void read::ulk()
{
    QFile file (nvalue);
    if (!file.open(QFile::ReadOnly | QFile::Text))
     {
         QMessageBox::warning (this, "Error", "File Could not Be Opened");
     }
  QString line;
  QTextStream in(&file);
  while (!in.atEnd())
   {
    line = in.readLine();
    ui->lineEdit_name_r->setText(ui->lineEdit_name_r->text()+line);
    qDebug() <<line;
   }
}

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[anda_skoa]

You can't assign to a "const" member or variable, it is "constant".

You can keep the const if you pass the value as an argument to read's constructor.

Cheers,
_