QT QTextBrowser problem with setText

[fäbs]

HI,
i have a problem with my qt program.
first of all i have a QTextBrowser and a Button. when the button is clicked it should call a method from a c++ class like this:

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);
 
}
 
MainWindow::~MainWindow()
{
    delete ui;
}
 
void MainWindow::on_Button_clicked()
{
    try{
        GUIController guiController;        
        guiController.somemethode();
 
    }
    catch (char const* err){
        cout << err << endl;
 
    }
 
}

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

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

void MainWindow::on_Button_clicked()
{
    try{
        GUIController guiController;        
        guiController.somemethode();

    }
    catch (char const* err){
        cout << err << endl;

    }

}

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This called methode should do something and then call a method from mainwindow class which should set Text to the textBrowser like this:

GUIController::GUIController()
{
 
}
 
GUIController::~GUIController()
{
 
}
 
void GUIController::somemethode{
    ...
    ...
    mainwindow.printToOutput(("text"));
 
}

GUIController::GUIController()
{

}

GUIController::~GUIController()
{

}

void GUIController::somemethode{
    ...
    ...
    mainwindow.printToOutput(("text"));
   
}

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MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);
 
}
 
MainWindow::~MainWindow()
{
    delete ui;
}
 
void MainWindow::printToOutput(QString text){
 
    ui->outputText->append(text);
 
}

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

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

void MainWindow::printToOutput(QString text){
   
    ui->outputText->append(text);
   
}

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But the problem is that the text doesn't appear in the QTextBrowser.
Has anybody an idea whats the problem?
i googled a long time and i think the problem is something with the "render loop" of the gui but i don't know how to fix it.

Thanks for help!

[anda_skoa]

Your GUIController instance does not have any access to the MainWindow instance.
How do you expect the controller to affect an object it doesn't know about?

Cheers,
_