Ok this is the (relevant) code i have:

quiz.cpp
Qt Code: 
  1. void Quiz::on_NextButton_clicked()
  2. {
  3.     QuizDialog question;
  4.     question.myfile.open("C:\\questions.txt");
  5.     if(question.myfile.is_open()){
  6.         question.next_question();
  7.  }
  8.  
  9. void Quiz::next_question(){
  10.     while(!(line=="<EOQ>")){
  11.                               getline(myfile, line);
  12.                               if(line == "<QUESTION_TEXT>"){
  13.                                                  getline(myfile, line);
  14.                                                  ui->QuestionLabel->setText(line.c_str());
  15.                                                  qDebug() << "Question: " << line.c_str();
  16.                                                  }
  17. }
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quiz.h
Qt Code: 
  1. #ifndef QUIZ
  2. #define QUIZ
  3.  
  4. #include <iostream>
  5. #include <fstream>
  6. #include <string>
  7. #include <QDialog>
  8. using namespace std;
  9.  
  10. namespace Ui {
  11.     class Quiz;
  12. }
  13.  
  14. class Quiz : public QDialog
  15. {
  16.     Q_OBJECT
  17.  
  18. public:
  19.     explicit Quiz(QWidget *parent = 0);
  20.     ~Quiz();
  21.     ifstream myfile;
  22.     string line;
  23.     void next_question();
  24.  
  25. private:
  26.     Ui::Quiz *ui;
  27.  
  28.  
  29. private slots:
  30.     void on_NextButton_clicked();
  31. };
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Ok so here's the problem. The file is opening fine. The function 'next_question();' then runs and "qDebug() << "Question: " << line.c_str();" does output the relevant information to the debugger.

However in the line above this, 'ui->QuestionLabel->setText(line.c_str());' i have asked for the caption on my form to be set to whatever the current value of line is. For some reason this does not seem to work. I know that the file is being access and I know that the correct line is being found. However I cannot output this information to the form. Could someone please explain what's up??


Thanks for your time and trouble.