title: How to remove focus from a QLineEdit when anyplace else on the window is clicked
body: <p>I'm working on a custom Qt button that allows you to edit the text on the button if you double click it. When the button is double clicked, a <code>QLineEdit</code> appears where the text on the button is allowing the user to edit the text on the button.  My requirement is that if the user clicks anywhere in the application window, the <code>QLineEdit</code> should disappear and cancel the edit operation. This works in some cases. Specifically, it works if I click on anything that is capable of text entry. Other portions of the window don't work as expected. I'll click on a blank portion of the application window, and the <code>QLineEdit</code> retains its focus. How can I remove its focus in these cases?</p>