QMap

[AnithaRagupathy]

hi,
How to use auto pointer in qmap.
I tried giving like QMap<qint32, auto_Ptr Name> m_xxx; .But it gives error.

[mchara]

hi, could you paste error you had?
and what do you mean by auto pointer? is it QPointer? Or maybe it is some data type not from qt?

[jpn]

How to use auto pointer in qmap.
I tried giving like QMap<qint32, auto_Ptr Name> m_xxx; .But it gives error.
First of all, get used to a habit of pasting errors you get. We are not mind-readers..

Secondly, "QMap<qint32, auto_Ptr Name>" is not valid C++. Try to be exact what you write because, again, we cannot guess if you actually wrote for example "QMap<qint32, auto_ptr<Name> >". Anyway, in case you mean std::auto_ptr, you cannot use it in containers. There are solutions like "counted_ptr" which can be used in containers.

[AnithaRagupathy]

I created auto pointer and wanted to use it like this..

typedef std::auto_ptr<IBaureihe> IBaureihePtr;
IBaureihePtr create_IBaureihe();
QMap<qint32, IBaureihePtr>::iterator lIter

Errors that i get

d:/Qt/4.3.0/src/corelib/tools/qhash.h: In constructor `QHashNode<int,
T>::QHashNode(int, const T&) [with T = LaufwegSbFr::IDSOrgaPtr]':
d:/Qt/4.3.0/src/corelib/tools/qhash.h:93: instantiated from `static void QHash<Key, T>::duplicat
ode(QHashData::Node*, void*) [with Key = qint32, T = LaufwegSbFr::IDSOrgaPtr]'
d:/Qt/4.3.0/src/corelib/tools/qhash.h:535: instantiated from `void QHash<Key, T>::detach_helper(
[with Key = qint32, T = LaufwegSbFr::IDSOrgaPtr]'
d:/Qt/4.3.0/src/corelib/tools/qhash.h:551: instantiated from `QHash<Key, T>& QHash<Key, T>::oper
or=(const QHash<Key, T>&) [with Key = qint32, T = LaufwegSbFr::IDSOrgaPtr]'
GlobalLaufwegImpl.cpp:528: instantiated from `void QHash<Key, T>::clear() [with Key = qint32, T
LaufwegSbFr::IDSOrgaPtr]'
GlobalLaufwegImpl.cpp:21: instantiated from here
d:/Qt/4.3.0/src/corelib/tools/qhash.h:215: passing `const
LaufwegSbFr::IDSOrgaPtr' as `this' argument of `std::auto_ptr<_Tp>::operator
std::auto_ptr_ref<_Tp1>() [with _Tp1 = LaufwegSbFr::IDSOrga, _Tp =
LaufwegSbFr::IDSOrga]' discards qualifiers

[jacek]

I created auto pointer and wanted to use it like this..

typedef std::auto_ptr<IBaureihe> IBaureihePtr;
When auto_ptr is destroyed, it destroys also the object it points to, which makes it completely unsuable for storing in any containers. Use boost::shared_ptr instead.

[mchara]

typedef std::auto_ptr<IBaureihe> IBaureihePtr;
IBaureihePtr create_IBaureihe();
QMap<qint32, IBaureihePtr>::iterator lIter

You're putting variable name instead of type try with


QMap<qint32, std::auto_ptr<IBaureihe> >::iterator lIter