src/add-ons/screen_savers/slideshowsaver/LiveSettings.h

   1 /*****************************************************************************/
   2 // LiveSettings
   3 // Written by Michael Wilber
   4 //
   5 // LiveSettings.h
   6 //
   7 // This class manages (saves/loads/locks/unlocks) a collection of BMessage
   8 // based settings. This class allows you to share settings between different
   9 // classes in different threads and receive notifications when the settings
  10 // change. This class makes it easy to share settings between a Translator
  11 // and its config panel or a Screen Saver and its config panel.
  12 //
  13 //
  14 // Copyright (C) Haiku
  15 //
  16 // Permission is hereby granted, free of charge, to any person obtaining a
  17 // copy of this software and associated documentation files (the "Software"),
  18 // to deal in the Software without restriction, including without limitation
  19 // the rights to use, copy, modify, merge, publish, distribute, sublicense,
  20 // and/or sell copies of the Software, and to permit persons to whom the
  21 // Software is furnished to do so, subject to the following conditions:
  22 //
  23 // The above copyright notice and this permission notice shall be included
  24 // in all copies or substantial portions of the Software.
  25 //
  26 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  27 // OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  28 // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  29 // THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  30 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  31 // FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  32 // DEALINGS IN THE SOFTWARE.
  33 /*****************************************************************************/
  34
  35 #ifndef LIVE_SETTINGS_H
  36 #define LIVE_SETTINGS_H
  37
  38 #include <Locker.h>
  39 #include <Path.h>
  40 #include <Message.h>
  41 #include <String.h>
  42 #include <vector>
  43 #include "LiveSettingsObserver.h"
  44 #include "LiveSetting.h"
  45
  46 class LiveSettings {
  47 public:
  48         LiveSettings(const char *settingsFile, LiveSetting *defaults,
  49                 int32 defCount);
  50
  51         LiveSettings *Acquire();
  52                 // increments the reference count, returns this
  53         LiveSettings *Release();
  54                 // decrements the reference count, deletes this
  55                 // when count reaches zero, returns this when
  56                 // ref count is greater than zero, NULL when
  57                 // ref count is zero
  58
  59         bool AddObserver(LiveSettingsObserver *observer);
  60                 // returns true if observer was added sucessfully,
  61                 // false if observer already in the list or error
  62         bool RemoveObserver(LiveSettingsObserver *observer);
  63                 // returns true if observer was removed successfully,
  64                 // false if observer not found or error
  65
  66         status_t LoadSettings();
  67         status_t LoadSettings(BMessage *pmsg);
  68         status_t SaveSettings();
  69         status_t GetConfigurationMessage(BMessage *pmsg);
  70
  71         bool SetGetBool(const char *name, bool *pVal = NULL);
  72         int32 SetGetInt32(const char *name, int32 *pVal = NULL);
  73
  74         void SetString(const char *name, const BString &str);
  75         void GetString(const char *name, BString &str);
  76
  77 private:
  78         const LiveSetting *FindLiveSetting(const char *name);
  79         ~LiveSettings();
  80                 // private so that Release() must be used
  81                 // to delete the object
  82
  83         void NotifySettingChanged(uint32 setting);
  84
  85         template <class T>
  86         bool GetValue(const char *name, T &val);
  87
  88         template <class T>
  89         bool SetValue(const char *name, const T &val);
  90
  91         BLocker fLock;
  92         int32 fRefCount;
  93         BPath fSettingsPath;
  94                 // where the settings file will be loaded from /
  95                 // saved to
  96
  97         BMessage fSettingsMsg;
  98                 // the actual settings
  99
 100         const LiveSetting *fDefaults;
 101         int32 fDefCount;
 102
 103         typedef std::vector<LiveSettingsObserver *> ObserverList;
 104         ObserverList fObservers;
 105 };
 106
 107 #endif // #ifndef LIVE_SETTTINGS_H
 108