In Qt 5.12.4, I try to dynamically create QSharedPointer<QMap<int,bool>>. I know that I can do
QMap<int, bool> mp = { { 1, true } };
as well as dynamically with
QMap<int, bool>* mpptr = new QMap<int, bool> { { 1, false } };
I know that I can create my QSharedPointer like so:
QMap<int, bool>* mpptr = new QMap<int, bool> { { 1, false } };
QSharedPointer<QMap<int, bool>> shraredmpptr(mpptr);
I want do this in one single shot, which I am not able to accomplish. I tried the most obvious
QSharedPointer<QMap<int, bool>> mpsptr =
QSharedPointer<QMap<int, bool>>::create(new QMap<int, bool> { { 1, false } });
but to no avail. The compiler gives me warnings that my types do not match but I do not see the point where I have to change the code so that it compiles. Any Ideas? Thanks in advance.
In file included from D:\Qt\5.12.4\mingw73_64\include/QtCore/qsharedpointer.h:48:0,
from D:\Qt\5.12.4\mingw73_64\include/QtCore/qdebug.h:54,
from D:\Qt\5.12.4\mingw73_64\include\QtCore/qloggingcategory.h:44,
from D:\Qt\5.12.4\mingw73_64\include\QtCore/QLoggingCategory:1,
from ..\..\..\..\myLibsQt\src\libs/a/foo.h:4,
from ..\..\..\..\myLibsQt\src\libs/a/bar.h:8,
from ..\..\..\..\myLibsQt\src\libs/b/baz.h:8,
from ..\..\..\..\myLibsQt\src\libs/c/bla.h:8,
from ..\..\..\..\myLibsQt\src\libs\c\blubb.cpp:1:
D:\Qt\5.12.4\mingw73_64\include/QtCore/qsharedpointer_impl.h: In instantiation of 'static QSharedPointer<T> QSharedPointer<T>::create(Args&& ...) [with Args = {QMap<int, bool>*}; T = QMap<int, bool>]':
..\..\..\..\myLibsQt\src\libs\c\blubb.cpp:27:80: required from here
D:\Qt\5.12.4\mingw73_64\include/QtCore/qsharedpointer_impl.h:445:9: error: no matching function for call to 'QMap<int, bool>::QMap(QMap<int, bool>*)'
new (ptr) T(std::forward<Args>(arguments)...);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from D:\Qt\5.12.4\mingw73_64\include/QtCore/qdebug.h:47:0,
from D:\Qt\5.12.4\mingw73_64\include\QtCore/qloggingcategory.h:44,
from D:\Qt\5.12.4\mingw73_64\include\QtCore/QLoggingCategory:1,
from ..\..\..\..\myLibsQt\src\libs/a/foo.h:4,
from ..\..\..\..\myLibsQt\src\libs/a/bar.h:8,
from ..\..\..\..\myLibsQt\src\libs/b/baz.h:8,
from ..\..\..\..\myLibsQt\src\libs/c/bla.h:8,
from ..\..\..\..\myLibsQt\src\libs\c\blubb.cpp:1:
D:\Qt\5.12.4\mingw73_64\include/QtCore/qmap.h:1164:22: note: candidate: QMap<K, V>::QMap(const std::map<Key, T>&) [with Key = int; T = bool]
Q_OUTOFLINE_TEMPLATE QMap<Key, T>::QMap(const std::map<Key, T> &other)
^~~~~~~~~~~~
D:\Qt\5.12.4\mingw73_64\include/QtCore/qmap.h:1164:22: note: no known conversion for argument 1 from 'QMap<int, bool>*' to 'const std::map<int, bool, std::less<int>, std::allocator<std::pair<const int, bool> > >&'
D:\Qt\5.12.4\mingw73_64\include/QtCore/qmap.h:343:12: note: candidate: QMap<K, V>::QMap(QMap<K, V>&&) [with Key = int; T = bool]
inline QMap(QMap<Key, T> &&other) Q_DECL_NOTHROW
^~~~
D:\Qt\5.12.4\mingw73_64\include/QtCore/qmap.h:343:12: note: no known conversion for argument 1 from 'QMap<int, bool>*' to 'QMap<int, bool>&&'
D:\Qt\5.12.4\mingw73_64\include/QtCore/qmap.h:622:8: note: candidate: QMap<K, V>::QMap(const QMap<K, V>&) [with Key = int; T = bool]
inline QMap<Key, T>::QMap(const QMap<Key, T> &other)
^~~~~~~~~~~~
D:\Qt\5.12.4\mingw73_64\include/QtCore/qmap.h:622:8: note: no known conversion for argument 1 from 'QMap<int, bool>*' to 'const QMap<int, bool>&'
D:\Qt\5.12.4\mingw73_64\include/QtCore/qmap.h:330:12: note: candidate: QMap<K, V>::QMap(std::initializer_list<std::pair<_T1, _T2> >) [with Key = int; T = bool]
inline QMap(std::initializer_list<std::pair<Key,T> > list)
^~~~
D:\Qt\5.12.4\mingw73_64\include/QtCore/qmap.h:330:12: note: no known conversion for argument 1 from 'QMap<int, bool>*' to 'std::initializer_list<std::pair<int, bool> >'
D:\Qt\5.12.4\mingw73_64\include/QtCore/qmap.h:328:12: note: candidate: QMap<K, V>::QMap() [with Key = int; T = bool]
inline QMap() Q_DECL_NOTHROW : d(static_cast<QMapData<Key, T> *>(const_cast<QMapDataBase *>(&QMapDataBase::shared_null))) { }
^~~~
D:\Qt\5.12.4\mingw73_64\include/QtCore/qmap.h:328:12: note: candidate expects 0 arguments, 1 provided
mingw32-make[1]: *** [Makefile.Debug:1488: debug/blubb.o] Error 1
Ok, I found an answer that works for me. the above one did not compile with msvc17 and with my arm toolchain. Also my first approach produces a memory leak.
The correct way to do is is
QSharedPointer<QMap<int, bool>> mpsptr(new QMap<int, bool> { { 1, false } });