include/wx/module.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        module.h
   3 // Purpose:     Modules handling
   4 // Author:      Wolfram Gloger/adapted by Guilhem Lavaux
   5 // Modified by:
   6 // Created:     04/11/98
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) Wolfram Gloger and Guilhem Lavaux
   9 // Licence:     wxWindows licence
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 #ifndef _WX_MODULE_H_
  13 #define _WX_MODULE_H_
  14
  15 #include "wx/object.h"
  16 #include "wx/list.h"
  17 #include "wx/dynarray.h"
  18
  19 // declare a linked list of modules
  20 class WXDLLIMPEXP_BASE wxModule;
  21 WX_DECLARE_USER_EXPORTED_LIST(wxModule, wxModuleList, WXDLLIMPEXP_BASE);
  22
  23 // and an array of class info objects
  24 WX_DEFINE_USER_EXPORTED_ARRAY_PTR(wxClassInfo *, wxArrayClassInfo,
  25                                     class WXDLLIMPEXP_BASE);
  26
  27
  28 // declaring a class derived from wxModule will automatically create an
  29 // instance of this class on program startup, call its OnInit() method and call
  30 // OnExit() on program termination (but only if OnInit() succeeded)
  31 class WXDLLIMPEXP_BASE wxModule : public wxObject
  32 {
  33 public:
  34     wxModule() {}
  35     virtual ~wxModule() {}
  36
  37     // if module init routine returns false the application
  38     // will fail to startup
  39
  40     bool Init() { return OnInit(); }
  41     void Exit() { OnExit(); }
  42
  43     // Override both of these
  44
  45         // called on program startup
  46
  47     virtual bool OnInit() = 0;
  48
  49         // called just before program termination, but only if OnInit()
  50         // succeeded
  51
  52     virtual void OnExit() = 0;
  53
  54     static void RegisterModule(wxModule *module);
  55     static void RegisterModules();
  56     static bool InitializeModules();
  57     static void CleanUpModules() { DoCleanUpModules(m_modules); }
  58
  59     // used by wxObjectLoader when unloading shared libs's
  60
  61     static void UnregisterModule(wxModule *module);
  62
  63 protected:
  64     static wxModuleList m_modules;
  65
  66     // the function to call from constructor of a deriving class add module
  67     // dependency which will be initialized before the module and unloaded
  68     // after that
  69     void AddDependency(wxClassInfo *dep)
  70     {
  71         wxCHECK_RET( dep, _T("NULL module dependency") );
  72
  73         m_dependencies.Add(dep);
  74     }
  75
  76 private:
  77     // initialize module and Append it to initializedModules list recursively
  78     // calling itself to satisfy module dependencies if needed
  79     static bool
  80     DoInitializeModule(wxModule *module, wxModuleList &initializedModules);
  81
  82     // cleanup the modules in the specified list (which may not contain all
  83     // modules if we're called during initialization because not all modules
  84     // could be initialized) and also empty m_modules itself
  85     static void DoCleanUpModules(const wxModuleList& modules);
  86
  87
  88     // module dependencies: contains
  89     wxArrayClassInfo m_dependencies;
  90
  91     // used internally while initiliazing/cleaning up modules
  92     enum
  93     {
  94         State_Registered,   // module registered but not initialized yet
  95         State_Initializing, // we're initializing this module but not done yet
  96         State_Initialized   // module initialized successfully
  97     } m_state;
  98
  99
 100     DECLARE_CLASS(wxModule)
 101 };
 102
 103 #endif // _WX_MODULE_H_
 104