Items are loaded from default JSON file in standard location at startup. If no items are found in file, example items are generated.

data/filehandler.cpp

@@ -28,4 +28,26 @@ bool FileHandler::saveToFile(const QJsonDocument& doc, const QString& fileName)
   return true;
 }
 
+QByteArray FileHandler::loadJSONDataFromFile(const QString fileName) {
+  QByteArray jsonData;
+  QFile file;
+  QString path = QStandardPaths::standardLocations(QStandardPaths::AppDataLocation).at(0);
+  file.setFileName(path + "/" + fileName);
+  if (file.exists()) {
+    qDebug() << "File found, reading content...";
+    const bool successfulOpened = file.open(QIODevice::ReadOnly | QIODevice::Text);
+    if (successfulOpened) {
+      // TODO learn and decide on the differences between "readAll" and using
+      // streams
+      jsonData = file.readAll();
+      file.close();
+    } else {
+      qWarning() << "File could not be opened!";
+    }
+  } else {
+    qInfo() << "File not found. Returning empty result...";
+  }
+  return jsonData;
+}
+
 FileHandler::FileHandler() {}

data/filehandler.h

@@ -3,10 +3,12 @@
 
 class QJsonDocument;
 class QString;
+class QByteArray;
 
 class FileHandler {
  public:
   static bool saveToFile(const QJsonDocument& doc, const QString& fileName);
+  static QByteArray loadJSONDataFromFile(const QString fileName);
 
  private:
   explicit FileHandler();