How can I capture the window close event when the user clicks on the "X"?: QT4, Linux, C++

How can I capture the window close event when the user clicks on the "X"?

Asked by: bleek

I need to run a function before the program shuts down. I have a system shutdown pushbutton that calls the function, but I need for the main window close "X" to react in the same fashion. The function displays a "are you sure?" dialog, and if "OK" closes certain files and stops the threads that are running. If "Cancel" is selected, it should continue processing.

I tried calling the function from the destructor (I removed the "delete ui" and put it in the function), but it immediately closes the window anyway.

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I found out that I need to overload the "closeEvent" function. I made a function "ShutdownProcess()" that handles the cleanup. If the user clicks on the "X", it works fine. However, if the "system shutdown" pushbutton is selected (function on_pbSystemShutdown_clicked() below), I can call the ShutdownProcess, which works OK, but I can't figure out how to get the application to close.

Any suggestions?? I tried calling "delete ui" like the destructor does, but it causes a seg fault.

void MainWindow::on_pbSystemShutdown_clicked()
{
    extern bool stopThreads;
    QCloseEvent* event;
 
    ShutdownProcess();
 
    if (stopThreads )
    {
        closeEvent( event);
  // close application - Do we need to check that shutdown received??
 
    }
 
void MainWindow::closeEvent(QCloseEvent* ce)
{
    extern bool stopThreads;
    bool bShutdown;
 
 
    if ( !stopThreads )
    {
        bShutdown = ShutdownProcess();
        if (bShutdown)
            ce->accept();
        else
            ce->ignore();
    }
    else
    {
        saveEvent->accept();
    }
}

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How can I capture the window close event when the user clicks on the "X"?

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QT4

Linux

C++

QT Programming Language

C / C++ / C# Editors and IDEs

Linux Programming

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