i have a problem when opening a window and close it for 30 times the application crashes and this is done in every window here are the code i used to open the window
m_pSupportWindow = new DownloadMainWindow(this);
connect(m_pSupportWindow, SIGNAL(destroyed()), this, SLOT(nullPointer()));
and here are the code i used in the window itself
m_pFeedBackWindow = NULL;
m_pSupportWindow = NULL;
m_pUpdateWindow = NULL;
why my application crashes when i open the window and close it for approximately 30 times?