c++ - Shared Preferences implementation -

my aim implement class can accessible anywhere, providing key value pairs;

class sharedresources { public:     static qmap <qstring,qvariant> *preferences; };  //initialization sharedresources.preferences = new qmap<qstring,qvariant>();  //store data sharedresources.preferences->insert("some_data",some_data);  //access data some_data = sharedresources.preferences->value("some_data"); 

but code not compile.

first error (got similar @ every usage):

/file:line: error: expected unqualified-id before '.' token  sharedresources.preferences = new qmap<qstring,qvariant>();                 ^ 

i broke c++ rules, are?

update: using :: error is:

/file:line: error: undefined reference `sharedresources::preferences' 

it's better in such case use statically rather dynamically allocated memory (i.e. without new).

your problem have declare , define static field well. in header file declare it, should defined somewhere in cpp file like:

// defines variable, default ctor (w/out parameters) qmap<qstring,qvariant> sharedresources::preferences;  

of course have link appropriate object file other modules (apart using header file declaration).