introduce DoubleLineEdit, a line edit which operates on a DoubleDescriptor

GUI/Views/CommonWidgets/DoubleLineEdit.cpp

+//  ************************************************************************************************
+//
+//  BornAgain: simulate and fit reflection and scattering
+//
+//! @file      GUI/Views/CommonWidgets/DoubleLineEdit.cpp
+//! @brief     Implements class DoubleLineEdit
+//!
+//! @homepage  http://www.bornagainproject.org
+//! @license   GNU General Public License v3 or higher (see COPYING)
+//! @copyright Forschungszentrum Jülich GmbH 2021
+//! @authors   Scientific Computing Group at MLZ (see CITATION, AUTHORS)
+//
+//  ************************************************************************************************
+
+#include "GUI/Views/CommonWidgets/DoubleLineEdit.h"
+#include "GUI/Views/CommonWidgets/GUIHelpers.h"
+#include <QDoubleValidator>
+
+DoubleLineEdit::DoubleLineEdit(QWidget* parent, const DoubleDescriptor& d)
+    : QLineEdit(parent), m_valueDescriptor(d)
+{
+    m_validator = new QDoubleValidator(0.0, 1e+200, 1000, this);
+    m_validator->setNotation(QDoubleValidator::ScientificNotation);
+    const double minimum =
+        d.limits.hasLowerLimit() ? std::max(d.limits.lowerLimit(), -1e+200) : -1e+200;
+    const double maximum =
+        d.limits.hasUpperLimit() ? std::min(d.limits.upperLimit(), +1e+200) : +1e+200;
+    m_validator->setRange(minimum, maximum, 1000);
+    setValidator(m_validator);
+
+    setBaseValue(m_valueDescriptor.get());
+
+    connect(this, &QLineEdit::editingFinished, this, &DoubleLineEdit::onEditingFinished);
+}
+
+void DoubleLineEdit::setBaseValue(double baseValue)
+{
+    setText(QString::number(baseValue, 'g'));
+}
+
+void DoubleLineEdit::onEditingFinished()
+{
+    const double new_value = text().toDouble();
+    if (new_value != m_valueDescriptor.get())
+        emit baseValueChanged(new_value);
+}

GUI/Views/CommonWidgets/DoubleLineEdit.h

+//  ************************************************************************************************
+//
+//  BornAgain: simulate and fit reflection and scattering
+//
+//! @file      GUI/Views/CommonWidgets/DoubleLineEdit.h
+//! @brief     Defines class DoubleLineEdit
+//!
+//! @homepage  http://www.bornagainproject.org
+//! @license   GNU General Public License v3 or higher (see COPYING)
+//! @copyright Forschungszentrum Jülich GmbH 2021
+//! @authors   Scientific Computing Group at MLZ (see CITATION, AUTHORS)
+//
+//  ************************************************************************************************
+
+#ifndef BORNAGAIN_GUI_VIEWS_COMMONWIDGETS_DOUBLELINEEDIT_H
+#define BORNAGAIN_GUI_VIEWS_COMMONWIDGETS_DOUBLELINEEDIT_H
+
+#include "GUI/Models/DoubleDescriptor.h"
+#include <QLineEdit>
+
+class QDoubleValidator;
+
+//! LineEdit to edit values in a scientific notation, operating on a DoubleDescriptor.
+//!
+//! In the future it can be enhanced to support units. At the moment, no DoubleDescriptor with units
+//! is used with a DoubleLineEdit, therefore the handling of units is not implemented yet. Only the
+//! naming is prepared already (also to have a naming alike to DoubleSpinBox).
+class DoubleLineEdit : public QLineEdit {
+    Q_OBJECT
+public:
+    DoubleLineEdit(QWidget* parent, const DoubleDescriptor& d);
+
+    //! Set the base value (unit is the one of the contained descriptor).
+    void setBaseValue(double baseValue);
+
+signals:
+    //! Emitted whenever the value changes.
+    //!
+    //! newBaseValue is in the unit of the valueDescriptor.
+    void baseValueChanged(double newBaseValue);
+
+private slots:
+    void onEditingFinished();
+
+private:
+    QDoubleValidator* m_validator;
+    DoubleDescriptor m_valueDescriptor;
+};
+
+
+#endif // BORNAGAIN_GUI_VIEWS_COMMONWIDGETS_DOUBLELINEEDIT_H