modelmenu.h Example File

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  #ifndef MODELMENU_H
  #define MODELMENU_H

  #include <QtWidgets/QMenu>
  #include <QtCore/QAbstractItemModel>

  // A QMenu that is dynamically populated from a QAbstractItemModel
  class ModelMenu : public QMenu
  {
      Q_OBJECT

  signals:
      void activated(const QModelIndex &index);
      void hovered(const QString &text);

  public:
      ModelMenu(QWidget *parent = 0);

      void setModel(QAbstractItemModel *model);
      QAbstractItemModel *model() const;

      void setMaxRows(int max);
      int maxRows() const;

      void setFirstSeparator(int offset);
      int firstSeparator() const;

      void setRootIndex(const QModelIndex &index);
      QModelIndex rootIndex() const;

      void setHoverRole(int role);
      int hoverRole() const;

      void setSeparatorRole(int role);
      int separatorRole() const;

      QAction *makeAction(const QIcon &icon, const QString &text, QObject *parent);

  protected:
      // add any actions before the tree, return true if any actions are added.
      virtual bool prePopulated();
      // add any actions after the tree
      virtual void postPopulated();
      // put all of the children of parent into menu up to max
      void createMenu(const QModelIndex &parent, int max, QMenu *parentMenu = 0, QMenu *menu = 0);

  private slots:
      void aboutToShow();
      void triggered(QAction *action);
      void hovered(QAction *action);

  private:
      QAction *makeAction(const QModelIndex &index);
      int m_maxRows;
      int m_firstSeparator;
      int m_maxWidth;
      int m_hoverRole;
      int m_separatorRole;
      QAbstractItemModel *m_model;
      QPersistentModelIndex m_root;
  };

  #endif // MODELMENU_H