Some quest about the closeEvent in QMainWindow

[cspp]

Hi all
I have an application with muti MainWindow. and thie close way:
The one way:

void MWindow::fileExit()
{
    close(TRUE);
}

void MWindow::fileExit()
{
    close(TRUE);
}

To copy to clipboard, switch view to plain text mode 

The another way:

void MWindow::closeEvent(QCloseEvent* ce)
{
    penv->m_WindowList->GoHead(); //the list of all QMainWindow
    do
    {
        if( pevn->m_WindowList->Object() == penv->currentWindow ) //
        {
             QMainWindow::closeEvent(ce);
             break;
        }
    }
    while(pevn->m_WindowList->GoNext())
}

void MWindow::closeEvent(QCloseEvent* ce)
{
    penv->m_WindowList->GoHead(); //the list of all QMainWindow
    do
    {
        if( pevn->m_WindowList->Object() == penv->currentWindow ) //
        {
             QMainWindow::closeEvent(ce);
             break;
        }
    }
    while(pevn->m_WindowList->GoNext())
}

To copy to clipboard, switch view to plain text mode 

The Destroy funtion

void MWindow::destroy()
{
    //release the memory
}

void MWindow::destroy()
{
    //release the memory
}

To copy to clipboard, switch view to plain text mode 

My question is:
if I call the fileExit,it will call the destroy!
and if I click the close button on the QMainWindow,it will call the closeEvent,but not
call the destroy(),so my memery and GDI will leak!

and I want to how,if I want to support the close button, how I can do to avoid the memory and GDI leak.

Thanks.

PS:my platform is WinXp,Qt336,MSVC6.0.

[wysota]

Why should destroy() be called if you never call it yourself? Closing a window doesn't cause it to be deleted, it would be hard to retrieve any data from it then If you want such behaviour, then pass the DestructiveClose flag to each of the windows.

[cspp]

you means if i want to call the destroy when click the close button on the QMainWindow, I neet set the WFlags Qt::WDestructiveClose?
Isee,I use the QMainWindow in default, and I will try it later,
Thanks