model.h Example File

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  #ifndef MODEL_H
  #define MODEL_H

  #include <QAbstractItemModel>
  #include <QFileIconProvider>
  #include <QIcon>
  #include <QVector>

  class Model : public QAbstractItemModel
  {
      Q_OBJECT

  public:
      Model(int rows, int columns, QObject *parent = 0);
      ~Model();

      QModelIndex index(int row, int column, const QModelIndex &parent) const Q_DECL_OVERRIDE;
      QModelIndex parent(const QModelIndex &child) const Q_DECL_OVERRIDE;

      int rowCount(const QModelIndex &parent) const Q_DECL_OVERRIDE;
      int columnCount(const QModelIndex &parent) const Q_DECL_OVERRIDE;

      QVariant data(const QModelIndex &index, int role) const Q_DECL_OVERRIDE;
      QVariant headerData(int section, Qt::Orientation orientation, int role) const Q_DECL_OVERRIDE;

      bool hasChildren(const QModelIndex &parent) const Q_DECL_OVERRIDE;
      Qt::ItemFlags flags(const QModelIndex &index) const Q_DECL_OVERRIDE;

  private:

      struct Node
      {
          Node(Node *parent = 0) : parent(parent), children(0) {}
          ~Node() { delete children; }
          Node *parent;
          QVector<Node> *children;
      };

      Node *node(int row, Node *parent) const;
      Node *parent(Node *child) const;
      int row(Node *node) const;

      QIcon services;
      int rc;
      int cc;
      QVector<Node> *tree;
      QFileIconProvider iconProvider;
  };

  #endif // MODEL_H