Break Qt Modeless Dialog

Question

From what I understand, in order to make the Modeless dialog, you have to allocate it in a heap. Having done something like this:

MyDialog* dlg = new MyDialog(this);
dlg->show();
dlg->raise();

Since exec () ignores the Modal property. However, a memory leak now occurs, since nothing frees the memory pointed to by the dlg pointer until the application is closed. I found one solution here http://tinf2.vub.ac.be/~dvermeir/manuals/KDE20Development-html/ch08lev1sec3.html#ch08list09 at the end of the page and wondered if there was a less cumbersome way to have a Modeless dialog.

Answer 1

finished deleteLater:

void MyDialog::MyDialog(QWidget *parent) {
    // ...
    connect(this, SIGNAL(finished(int)), SLOT(deleteLater)));
}

, finished ( , , , ).

Answer 2

Qt:: WA_DeleteOnClose, , /, QWeakPointer ( QPointer) /, :

void MyWindow::openDialog() {    
    static QWeakPointer<MyDialog> dlg_;
    if (!dlg_)
        dlg_ = new MyDialog(this);

    MyDialog *dlg = dlg_.data();
    dlg->setAttribute(Qt::WA_DeleteOnClose);
    dlg->show();
    dlg->raise();
    dlg->activateWindow();
}

Answer 3

dlg->setAttribute(Qt::WA_DeleteOnClose);

a -dynamically alloc-member, .. :

// constructor
  : dialog_(0)

// member function
{
  if (! dialog_)
    dialog_ = new MyDialog(this);

  dialog_->show();
  dialog_->raise();
}

, , .