File indexing completed on 2024-04-14 03:40:45

 /*
     KmPlot - a math. function plotter for the KDE-Desktop
 
     SPDX-FileCopyrightText: 2006 David Saxton <david@bluehaze.org>
 
     This file is part of the KDE Project.
     KmPlot is part of the KDE-EDU Project.
 
     SPDX-License-Identifier: GPL-2.0-or-later
 
 */
 
 #ifndef KGRADIENTDIALOG_H
 #define KGRADIENTDIALOG_H
 
 #include <QDialog>
 #include <QGradient>
 #include <QPushButton>
 #include <QWidget>
 
 class QMouseEvent;
 class QPaintEvent;
 class QStyleOptionButton;
 
 /**
  * \short A color-gradient strip with arrows to change the stops.
  *
  * Displays a color gradient for editing. Color stops can be added, removed or
  * repositioned by the user via the mouse.
  *
  * This widget can't change the colors used in the gradient however. For that,
  * you should either:
  *
  * \li Use KGradientDialog, or
  * \li Connect to the colorChanged signal, provide your own color editing
  *     widgets, and call setColor as appropriate.
  *
  * \see QGradient
  */
 class KGradientEditor : public QWidget
 {
     Q_OBJECT
     Q_PROPERTY(Qt::Orientation orientation READ orientation WRITE setOrientation)
     Q_PROPERTY(QGradient gradient READ gradient WRITE setGradient USER true)
 
 public:
     explicit KGradientEditor(QWidget *parent);
     ~KGradientEditor();
 
     /**
      * \return the current color-gradient.
      */
     QGradient gradient() const
     {
         return m_gradient;
     }
     /**
      * \return the currently selected color.
      */
     QColor color() const
     {
         return m_currentStop.second;
     }
     /**
      * Set the orientation of the gradient strip.
      */
     void setOrientation(Qt::Orientation orientation);
     /**
      * \return the orientation of the gradient strip.
      */
     Qt::Orientation orientation() const
     {
         return m_orientation;
     }
 
     QSize minimumSizeHint() const Q_DECL_OVERRIDE;
 
 public Q_SLOTS:
     /**
      * Set the current gradient being edited.
      */
     void setGradient(const QGradient &gradient);
     /**
      * Set the color of the currently selected color-stop.
      */
     void setColor(const QColor &color);
     /**
      * Removes the currently selected stop.
      */
     void removeStop();
 
 Q_SIGNALS:
     /**
      * Emitted when a color-stop is selected (e.g. when it is clicked on
      * or the previously selected color is removed).
      */
     void colorSelected(const QColor &color);
     /**
      * Emitted when the gradient changes.
      */
     void gradientChanged(const QGradient &gradient);
 
 protected:
     void paintEvent(QPaintEvent *e) Q_DECL_OVERRIDE;
     void mousePressEvent(QMouseEvent *e) Q_DECL_OVERRIDE;
     void mouseMoveEvent(QMouseEvent *e) Q_DECL_OVERRIDE;
     void mouseReleaseEvent(QMouseEvent *e) Q_DECL_OVERRIDE;
     void mouseDoubleClickEvent(QMouseEvent *e) Q_DECL_OVERRIDE;
     void contextMenuEvent(QContextMenuEvent *e) Q_DECL_OVERRIDE;
 
 private:
     /**
      * Attempts to get the arrow under the mouse, updating m_currentStop
      * to the corresponding stop if an arrow was found.
      * \return true if an arrow was under \p mousePos
      * \return false if an arrow wasn't under \p mousePos
      */
     bool getGradientStop(const QPoint &mousePos);
     /**
      * Updates the current stop, redraws the widget and emits
      * colorSelected.
      */
     void setCurrentStop(const QGradientStop &stop);
     /**
      * Updates m_gradient, redraws the widget and emits gradientChanged.
      */
     void setGradient(const QGradientStops &stops);
     /**
      * Draws the given gradient stop.
      */
     void drawArrow(QPainter *painter, const QGradientStop &stop);
     /**
      * Converts from \p stop (ranging from 0 to 1) to a horizontal or
      * vertical (depending on the current orientation) widget coordinate.
      */
     double toArrowPos(double stop) const;
     /**
      * Inverse of toArrowPos; converts from the widget coordinate \p pos
      * to a stop position, which is guaranteed to be between 0 and 1.
      */
     double fromArrowPos(double pos) const;
     /**
      * Find a gradient stop to be selected. This is called after e.g. the
      * currently selected stop is deleted.
      */
     void findGradientStop();
 
     double m_clickOffset; // from the center of the arrow
     bool m_haveArrow; // true when an arrow has been clicked on
     QGradientStop m_currentStop;
     QGradient m_gradient;
     Qt::Orientation m_orientation;
 };
 
 /**
  * \short A dialog for getting a QGradient.
  *
  * This dialog contains a KGradientEditor for editing the gradient stops and
  * a selection of widgets for changing the current color.
  *
  * Example:
  *
  * \code
  *  QGradient gradient;
  *  int result = KGradientDialog::getColor( gradient );
  *  if ( result == KGradientDialog::Accepted )
  *      ...
  * \endcode
  */
 class KGradientDialog : public QDialog
 {
     Q_OBJECT
 
 public:
     KGradientDialog(QWidget *parent, bool modal);
     ~KGradientDialog();
 
     /**
      * Creates a modal gradient dialog, lets the user choose a gradient,
      * and returns when the dialog is closed.
      *
      * The initial gradient will be the one passed in \p gradient, and the
      * chosen gradient is returned in this argument. If the user Cancels
      * the dialog instead of Ok'ing it, then \p gradient will remain
      * unchanged.
      *
      * \returns QDialog::result()
      */
     static int getGradient(QGradient &gradient, QWidget *parent = nullptr);
 
     /**
      * \return the current gradient.
      */
     QGradient gradient() const;
 
 public Q_SLOTS:
     /**
      * Sets the current gradient.
      */
     void setGradient(const QGradient &gradient);
 
 Q_SIGNALS:
     /**
      * Emitted when the current gradient changes.
      */
     void gradientChanged(const QGradient &gradient);
 
 private:
     class QColorDialog *m_colorDialog;
     KGradientEditor *m_gradient;
 };
 
 /**
  * \short A button to display and edit color gradients
  *
  * The button contains and displays a color gradient (see QGradient). When
  * clicked on, it creates a KGradientDialog for editing the gradient.
  */
 class KGradientButton : public QPushButton
 {
     Q_OBJECT
     Q_PROPERTY(QGradient gradient READ gradient WRITE setGradient USER true)
 
 public:
     explicit KGradientButton(QWidget *parent = nullptr);
     ~KGradientButton();
 
     /**
      * \return the current gradient.
      */
     QGradient gradient() const
     {
         return m_gradient;
     }
 
     QSize sizeHint() const Q_DECL_OVERRIDE;
 
 Q_SIGNALS:
     /**
      * Emitted when the current gradient changes.
      */
     void gradientChanged(const QGradient &gradient);
 
 public Q_SLOTS:
     /**
      * Sets the current gradient.
      */
     void setGradient(const QGradient &gradient);
 
 protected Q_SLOTS:
     /**
      * Invokes the KGradientDialog for selecting a gradient.
      */
     void chooseGradient();
 
 protected:
     void paintEvent(QPaintEvent *pe) Q_DECL_OVERRIDE;
 
 private:
     void initStyleOption(QStyleOptionButton *opt) const;
     QGradient m_gradient;
 };
 
 #endif // KGRADIENTEDITOR_H