How Do I Refresh a View if the Delegate Changes its Display Format?

[aamer4yu]

You could have also used something in MainWindow ctor like -

connect(m_button, SIGNAL(clicked()), this, SLOT(toggleFormat()));
// and in MainWindow::toggleFormat()
MainWindow::toggleFormat()
{   del->toggleFormat();
     m_view->update();
}

connect(m_button, SIGNAL(clicked()), this, SLOT(toggleFormat()));
// and in MainWindow::toggleFormat()
MainWindow::toggleFormat()
{   del->toggleFormat();
     m_view->update();
}

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This would keep the work of delegate to only render. I dont think it was good that delegate tells view to update. I guess its the controller / creator's job.

[ChrisW67]

In the real application the signal to change date or duration format comes from outside of the affected view (I just put it there for the example). I could connect that signal to a view slot as you suggest and, yes, it probably is neater. Thanks for the thought.