How to force capital letters in input field?

[wysota]

Just please tell us why you didn't want to use the validator approach. You could have written about 5-10 lines of code to do what you wanted but you decided to write many more lines of code that don't do what you wanted (see my point on pasting text into the box). If the user wants to type in capital letters then it will be easier for him to enable caps lock than to check some boxes on your ui.

[trallallero]

I've used the same system: sending a signal when a key has been pressed.

I need to capitalise all the user inputs but not what the gui automatically inserts, so a signal is much more efficient than a validator.

And it's 10 lines

protected:
      void keyPressEvent(QKeyEvent* e)
      {
         if (e->key() >= Qt::Key_A && e->key() <= Qt::Key_Z)
            emit KeyPressed(e->text().toUpper().at(0));
         else
            QLineEdit::keyPressEvent(e);
      }
   signals:
      void KeyPressed(const QChar&);

protected:
      void keyPressEvent(QKeyEvent* e)
      {
         if (e->key() >= Qt::Key_A && e->key() <= Qt::Key_Z)
            emit KeyPressed(e->text().toUpper().at(0));
         else
            QLineEdit::keyPressEvent(e);
      }
   signals:
      void KeyPressed(const QChar&);

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