Deallocate memory to singleton class which access database ?
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@J-Hilk ,@jsulm ,@jsulm ,@KroMignon Thanks for enormous support.
i have written like it below and now its not show any error:
void SqliteManagerBGSync::cleanup() { for (short int i =0 ; i<sizeof(sqliteManagerMap);i++) { delete sqliteManagerMap[i]; } sqliteManagerMap.clear(); }@Qt-embedded-developer
usingsizeofis almost certainly wrong here.std::map has a size() function, please use that.
https://en.cppreference.com/w/cpp/container/map/size -
@KroMignon i can not enable it like that because any change like that not allowed in my device.
@Qt-embedded-developer said in Deallocate memory to singleton class which access database ?:
i can not enable it like that because any change like that not allowed in my device.
As @jsulm already wrote before, replace
autowith the corresponding type:for(std::map<int,SqliteManagerBGSync*>::iterator it = sqliteManagerMap::begin(); it != sqliteManagerMap::end(); ++it) { ... }It is an old maxim of mine that when you have excluded the impossible, whatever remains, however improbable, must be the truth. (Sherlock Holmes)
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@Qt-embedded-developer said in Deallocate memory to singleton class which access database ?:
i can not enable it like that because any change like that not allowed in my device.
As @jsulm already wrote before, replace
autowith the corresponding type:for(std::map<int,SqliteManagerBGSync*>::iterator it = sqliteManagerMap::begin(); it != sqliteManagerMap::end(); ++it) { ... }@KroMignon
IIRC range based for loops is a c++11 feature in itself 🤔never mind, I think need a break!
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@KroMignon
IIRC range based for loops is a c++11 feature in itself 🤔never mind, I think need a break!
@J-Hilk said in Deallocate memory to singleton class which access database ?:
IIRC range based for loops is a c++11 feature in itself 🤔
Are you sure? I don't believe that
std::map<>::iteratorsupport is comming with C++11.It is an old maxim of mine that when you have excluded the impossible, whatever remains, however improbable, must be the truth. (Sherlock Holmes)
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@J-Hilk said in Deallocate memory to singleton class which access database ?:
IIRC range based for loops is a c++11 feature in itself 🤔
Are you sure? I don't believe that
std::map<>::iteratorsupport is comming with C++11.@KroMignon I think @J-Hilk misunderstood your code: you are not using range based loop
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@Qt-embedded-developer said in Deallocate memory to singleton class which access database ?:
i can not enable it like that because any change like that not allowed in my device.
As @jsulm already wrote before, replace
autowith the corresponding type:for(std::map<int,SqliteManagerBGSync*>::iterator it = sqliteManagerMap::begin(); it != sqliteManagerMap::end(); ++it) { ... }@KroMignon Here inside for loop i need to write
for(std::map<int,SqliteManagerBGSync*>::iterator it = sqliteManagerMap::begin(); it != sqliteManagerMap::end(); ++it) { delete it; }or what i need to write to deallocate memory ?
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@KroMignon Here inside for loop i need to write
for(std::map<int,SqliteManagerBGSync*>::iterator it = sqliteManagerMap::begin(); it != sqliteManagerMap::end(); ++it) { delete it; }or what i need to write to deallocate memory ?
@Qt-embedded-developer said in Deallocate memory to singleton class which access database ?:
delete it;
delete it->second;
of course
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@KroMignon Here inside for loop i need to write
for(std::map<int,SqliteManagerBGSync*>::iterator it = sqliteManagerMap::begin(); it != sqliteManagerMap::end(); ++it) { delete it; }or what i need to write to deallocate memory ?
@Qt-embedded-developer said in Deallocate memory to singleton class which access database ?:
or what i need to write to deallocate ?
Please, take time to read std::map<> documentation.
You are using a map iterator, so it is a container object which gives you access to key and value.delete itdo not make sense!You want to delete the pointer hold in the value part:
delete it->second -
@Qt-embedded-developer said in Deallocate memory to singleton class which access database ?:
or what i need to write to deallocate ?
Please, take time to read std::map<> documentation.
You are using a map iterator, so it is a container object which gives you access to key and value.delete itdo not make sense!You want to delete the pointer hold in the value part:
delete it->secondThis post is deleted! -
@Qt-embedded-developer said in Deallocate memory to singleton class which access database ?:
i can not enable it like that because any change like that not allowed in my device.
As @jsulm already wrote before, replace
autowith the corresponding type:for(std::map<int,SqliteManagerBGSync*>::iterator it = sqliteManagerMap::begin(); it != sqliteManagerMap::end(); ++it) { ... }@KroMignon Hi when i put sqliteManagerMap::begin() and sqliteManagerMap::end() i am getting error .
like below :
for(std::map<int,SqliteManagerBGSync *>::iterator it = sqliteManagerMap::begin(); it != sqliteManagerMap::end(); ++it)
but when i put sqliteManagerMap.begin() then i am getting no error.
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@KroMignon Hi when i put sqliteManagerMap::begin() and sqliteManagerMap::end() i am getting error .
like below :
for(std::map<int,SqliteManagerBGSync *>::iterator it = sqliteManagerMap::begin(); it != sqliteManagerMap::end(); ++it)
but when i put sqliteManagerMap.begin() then i am getting no error.
@Qt-embedded-developer said in Deallocate memory to singleton class which access database ?:
sqliteManagerMap::begin() and sqliteManagerMap::end()
As already explained in your other thread: begin() and end() are non-static methods, so you call them with . not :: !
Please learn C++ and read documentation! -
@KroMignon Hi when i put sqliteManagerMap::begin() and sqliteManagerMap::end() i am getting error .
like below :
for(std::map<int,SqliteManagerBGSync *>::iterator it = sqliteManagerMap::begin(); it != sqliteManagerMap::end(); ++it)
but when i put sqliteManagerMap.begin() then i am getting no error.
@Qt-embedded-developer said in Deallocate memory to singleton class which access database ?:
for(std::map<int,SqliteManagerBGSync *>::iterator it = sqliteManagerMap::begin(); it != sqliteManagerMap::end(); ++it)
Sorry my fault, as @jsulm already told, this are not static class methods. You want to call class instance methode:
for(std::map<int,SqliteManagerBGSync *>::iterator it = sqliteManagerMap.begin(); it != sqliteManagerMap.end(); ++it)Was a long day yesterday!
