How to access a struct from another another C++ class?

Question

Hello I have a struct in a TreeItem class:

// TreeItem.h
class TreeItem
{
public:

  struct TreePair
  {
    QString   sa_key;
    QVariant  sa_value;
  };

  //... blabla
}

I would like access that struct TreePair from another class TreeModel , which has class TreeItem already formarded in its header:

// TreeModel.h
class TreeItem;
class TreeModel : public QAbstractItemModel
{
    Q_OBJECT
    //..
}

// TreeModel.cpp
TreeModel::TreeModel(const QStringList &headers, const QString &data, QObject *parent)
  : QAbstractItemModel(parent)
{
  QVector<TreePair> rootData; // TreePair was not declared in this scope
}

My strcut was not declared in this scope?? In every class it was already automatically set like

#ifndef _TREEITEM_H
#define _TREEITEM_H
#endif

`TreeItem::TreePair` note that `TreeItem` must be defined before `TreeModel` in that case. Why not make `TreePair` a separate definition? — BeyelerStudios, Aug 12 '15 at 11:42

score 1 · Accepted Answer · answered Aug 12 '15 at 11:43

1

Since TreePair is nested inside TreeItem, it needs to be

QVector<TreeItem::TreePair> rootData;

answered Aug 12 '15 at 11:43

m.s.

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Error: incomplete type 'TreeItem' used in nested name specifier QVector rootData; – MarkZltr Aug 12 '15 at 12:00
1

@MarkZltr you must include `TreeItem.h` within `TreeModel.cpp` – m.s. Aug 12 '15 at 12:02
1

@MarkZltr forward declaration won't work see [the answer to this](http://stackoverflow.com/questions/1021793/how-do-i-forward-declare-an-inner-class) – Tomasz Sodzawiczny Aug 12 '15 at 12:08

How to access a struct from another another C++ class?

1 Answers1