How to retrive data saved using Setdata?

[parshant65@gmail.com]

I have used QStandardItem::SetData to save data for each tree item, code is below:
m_htHashItem->setData(QVariant(QVariant::UserType, m_pCurrMapData), MyClassRole);

Now I need to retrieve it back on item click event
MAP_DATA* p = static_cast< MAP_DATA *> (index.data(MyClassRole).value());

but I am getting error:
error: C2783: 'T QVariant::value(void) const' : could not deduce template argument for 'T'

[ChrisW67]

Something like:

struct MAP_DATA { };
Q_DECLARE_METATYPE(MAP_DATA*)

// and assuming
MAP_DATA *m_pCurrMapData;

// Elsewhere
m_htHashItem->setData(QVariant(m_pCurrMapData), MyClassRole);

MAP_DATA* p = index.data(MyClassRole).value<MAP_DATA*>();

follows from the examples in the QVariant::value() docs

[parshant65@gmail.com]

Thanks for reply...not getting any error but getting NULL / 0 while getting value back.

struct MAP_DATA { };

enum MyRoles {
MyClassRole = Qt::UserRole + 1
};

Q_DECLARE_METATYPE(MAP_DATA*)

//set address of a linked list node
m_htHashItem->setData(QVariant(QVariant::UserType, m_pCurrMapData), MyClassRole);

//gettting same node
MAP_DATA* pFileData = index.data(MyClassRole).value<MAP_DATA*>();

But I am getting ZERO for pFileData everytime. Please let me know where am I wrong?

[anda_skoa]

Compare your setData() call with that ChrisW67 provided.
Notice the difference.
Fix.

Cheers,
_

[parshant65@gmail.com]

If I use SetData described by ChrisW67 then I am getting error in QT 5:
error: C2248: 'QVariant::QVariant' : cannot access private member declared in class 'QVariant'

[anda_skoa]

Try


m_htHashItem->setData(QVariant::fromValue(m_pCurrMapData), MyClassRole);


Cheers,
_