Qt 5.6 | Qt Core | JSON Save Game Example | game.cpp Example File

Qt 5.6.3 Reference Documentation

# game.cpp Example File

json/savegame/game.cpp

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      #include "game.h"

      #include <QFile>
      #include <QJsonArray>
      #include <QJsonDocument>

      Game::Game()
      {
      }

      const Character &Game::player() const
      {
          return mPlayer;
      }

      const QList<Level> &Game::levels() const {
          return mLevels;
      }

      void Game::newGame() {
          mPlayer = Character();
          mPlayer.setName(QStringLiteral("Hero"));
          mPlayer.setClassType(Character::Archer);
          mPlayer.setLevel(15);

          mLevels.clear();

          Level village;
          QList<Character> villageNpcs;
          villageNpcs.append(Character(QStringLiteral("Barry the Blacksmith"), 10, Character::Warrior));
          villageNpcs.append(Character(QStringLiteral("Terry the Trader"), 10, Character::Warrior));
          village.setNpcs(villageNpcs);
          mLevels.append(village);

          Level dungeon;
          QList<Character> dungeonNpcs;
          dungeonNpcs.append(Character(QStringLiteral("Eric the Evil"), 20, Character::Mage));
          dungeonNpcs.append(Character(QStringLiteral("Eric's Sidekick #1"), 5, Character::Warrior));
          dungeonNpcs.append(Character(QStringLiteral("Eric's Sidekick #2"), 5, Character::Warrior));
          dungeon.setNpcs(dungeonNpcs);
          mLevels.append(dungeon);
      }

      bool Game::loadGame(Game::SaveFormat saveFormat)
      {
          QFile loadFile(saveFormat == Json
              ? QStringLiteral("save.json")
              : QStringLiteral("save.dat"));

          if (!loadFile.open(QIODevice::ReadOnly)) {
              qWarning("Couldn't open save file.");
              return false;
          }

          QByteArray saveData = loadFile.readAll();

          QJsonDocument loadDoc(saveFormat == Json
              ? QJsonDocument::fromJson(saveData)
              : QJsonDocument::fromBinaryData(saveData));

          read(loadDoc.object());

          return true;
      }

      bool Game::saveGame(Game::SaveFormat saveFormat) const
      {
          QFile saveFile(saveFormat == Json
              ? QStringLiteral("save.json")
              : QStringLiteral("save.dat"));

          if (!saveFile.open(QIODevice::WriteOnly)) {
              qWarning("Couldn't open save file.");
              return false;
          }

          QJsonObject gameObject;
          write(gameObject);
          QJsonDocument saveDoc(gameObject);
          saveFile.write(saveFormat == Json
              ? saveDoc.toJson()
              : saveDoc.toBinaryData());

          return true;
      }

      void Game::read(const QJsonObject &json)
      {
          mPlayer.read(json["player"].toObject());

          mLevels.clear();
          QJsonArray levelArray = json["levels"].toArray();
          for (int levelIndex = 0; levelIndex < levelArray.size(); ++levelIndex) {
              QJsonObject levelObject = levelArray[levelIndex].toObject();
              Level level;
              level.read(levelObject);
              mLevels.append(level);
          }
      }

      void Game::write(QJsonObject &json) const
      {
          QJsonObject playerObject;
          mPlayer.write(playerObject);
          json["player"] = playerObject;

          QJsonArray levelArray;
          foreach (const Level level, mLevels) {
              QJsonObject levelObject;
              level.write(levelObject);
              levelArray.append(levelObject);
          }
          json["levels"] = levelArray;
      }