text: #ifndef QVALIDATEDLINEEDIT_H
  #define QVALIDATEDLINEEDIT_H
  
  #include <QLineEdit>
  
  // Line edit that can be marked as "invalid" to show input validation feedback. When marked as invalid,
  // it will get a red background until it is focused.
  class QValidatedLineEdit : public QLineEdit
  {
      Q_OBJECT
      
  public:
      explicit QValidatedLineEdit(QWidget *parent = 0);
      void clear();
  
  protected:
      void focusInEvent(QFocusEvent *evt);
  
  private:
      bool valid;
  
  public slots:
      void setValid(bool valid);
  
  private slots:
      void markValid();
      
  };
  
  #endif // QVALIDATEDLINEEDIT_H
  