Image processing error

[bachkimfly]

If don't made MainWindow a member variable of a QDialog, how to can executable event in QDialog. So what is your idea?

[wysota]

If don't made MainWindow a member variable of a QDialog, how to can executable event in QDialog.

I don't understand what you mean.

[bachkimfly]

I want to catch event slider value changed, but brightness processing function which at MainWindow, if don't made MainWindow as a member variable of a BrightnessContrast dialog, i dont know to executable event slider value changed. your idea!

P/s: now, it's 5:22 AM, a tonight don't sleep, i want to go to sleep

[wysota]

I want to catch event slider value changed, but brightness processing function which at MainWindow, if don't made MainWindow as a member variable of a BrightnessContrast dialog, i dont know to executable event slider value changed. your idea!

Don't you already have an instance of the main window which launched the dialog? Do you understand the difference between a class and an instance of a class?

[bachkimfly]

Alright! I need have to initialize object of MainWindow class, right?. I asked in #9.
So what is I can understand for "made MainWindow a member variable of a QDialog subclass". Patently, I misconstrued.

[wysota]

Alright! I need have to initialize object of MainWindow class, right?

No, I'm assuming you already have such an object somewhere.

Let's make a deal - if you keep ignoring my questions, I will start ignoring yours.

[bachkimfly]

No, I'm assuming you already have such an object somewhere.

Let's make a deal - if you keep ignoring my questions, I will start ignoring yours.

I don't ignore, I answered by the question "I need have to initialize object of MainWindow class, right?". That means I don't have an instance of the main window which launched the dialog and I understand the difference between a class and an instance of a class. I think so.

But I feel we are going around.

[wysota]

Did you initialize the imageLabel pointer with a QLabel instance? Can you show us the code where you did that?

[bachkimfly]

I did.

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);
 
    imageLabel = new QLabel;
    imageLabel->setBackgroundRole(QPalette::Base);
    imageLabel->setSizePolicy(QSizePolicy::Ignored, QSizePolicy::Ignored);
    imageLabel->setScaledContents(true);
 
    scrollArea = new QScrollArea;
    scrollArea->setBackgroundRole(QPalette::Dark);
    scrollArea->setWidget(imageLabel);
    setCentralWidget(scrollArea);
    statusBar()->addWidget(ui->frame, 9);
    statusBar()->addWidget(ui->spinBoxZoom, 1);
    ui->frame->setFocus();
    //ui->mainToolBar->setStyleSheet("QToolBar{background-color: rgb(60,60,60);}");
    ui->mainToolBar->setBackgroundRole(QPalette::Window);
}

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

    imageLabel = new QLabel;
    imageLabel->setBackgroundRole(QPalette::Base);
    imageLabel->setSizePolicy(QSizePolicy::Ignored, QSizePolicy::Ignored);
    imageLabel->setScaledContents(true);

    scrollArea = new QScrollArea;
    scrollArea->setBackgroundRole(QPalette::Dark);
    scrollArea->setWidget(imageLabel);
    setCentralWidget(scrollArea);
    statusBar()->addWidget(ui->frame, 9);
    statusBar()->addWidget(ui->spinBoxZoom, 1);
    ui->frame->setFocus();
    //ui->mainToolBar->setStyleSheet("QToolBar{background-color: rgb(60,60,60);}");
    ui->mainToolBar->setBackgroundRole(QPalette::Window);
}

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[wysota]

I noticed now that the back trace you posted is missing two first frames. Can you post the complete backtrace?

[bachkimfly]

Yes, missing 2 first frames. That time I only post backtrace for 4 breakpoints. Now, I edited source code, I have to back to previous code to have full backtrace.
I want to ask that how to invoke brightness processing when slider value changed in Dialog.

[wysota]

I don't need your breakpoints. When the program crashes, print the backtrace from the debugger and post it here.