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();

formats/jsonparser.cpp

@@ -51,7 +51,7 @@ QJsonArray JsonParser::extractItemArray(const QByteArray& jsonData, const QStrin
 
   } else {
     QJsonObject rootObject = doc.object();
-    itemArray              = rootObject.value(QString("items")).toArray();
+    itemArray              = rootObject.value(objectName).toArray();
   }
 
   return itemArray;

genericcore.cpp

@@ -90,6 +90,10 @@ QUndoStack* GenericCore::getModelUndoStack() const { return m_modelUndoStack; }
 
 std::shared_ptr<TableModel> GenericCore::getModel() const { return m_mainModel; }
 
+/**
+ * Save items to default file (in standard location).
+ * @brief GenericCore::saveItems Saves item fo file.
+ */
 void GenericCore::saveItems() {
   qDebug() << "saving items...";
 
@@ -108,6 +112,29 @@ void GenericCore::saveItems() {
 void GenericCore::setupModels() {
   m_mainModel = make_shared<TableModel>(m_modelUndoStack, this);
   // TODO add QAbstractItemModelTester
+  initModelData();
+}
+
+/**
+ * Initializing model with data. Tries to read items from default file. Generating example items as
+ * fallback.
+ * @brief GenericCore::initModelData
+ */
+void GenericCore::initModelData() {
+  qInfo() << "Trying to read model data from file...";
+  const QByteArray jsonDoc = FileHandler::loadJSONDataFromFile("items.json");
+  // qDebug() << "jsonDoc:" << jsonDoc;
+  // TODO decide on lack of file(s) (config, data) if example items should be generated
+  //      (see welcome wizard)
+  if (jsonDoc.isEmpty()) {
+    qDebug() << "No item content in file. Generating example items...";
+    const QByteArray exampleItems = m_mainModel->generateExampleItems();
+    m_mainModel->insertItems(0, exampleItems);
+  } else {
+    qDebug() << "Item in file found.";
+    m_mainModel->insertItems(0, jsonDoc);
+  }
+  m_modelUndoStack->clear();
 }
 
 QString GenericCore::getMaintenanceToolFilePath() const {

genericcore.h

@@ -35,6 +35,7 @@ class GenericCore : public QObject {
   std::shared_ptr<TableModel> m_mainModel;
 
   void setupModels();
+  void initModelData();
 
   QString getMaintenanceToolFilePath() const;
 };

model/tablemodel.cpp

@@ -17,21 +17,35 @@ QHash<int, QByteArray> TableModel::ROLE_NAMES = {{NameRole, "Name"},
                                                  {FactorRole, "Factor"}};
 QList<QString> TableModel::intColumns         = {"Amount", "Factor"};
 
+QByteArray TableModel::generateExampleItems() {
+  QJsonDocument doc = QJsonDocument();
+  QJsonObject rootObject;
+  QJsonArray array;
+
+  for (int row = 0; row < 5; ++row) {
+    QJsonObject itemObject;
+    //  itemObject.insert("uuid", m_uuid.toString());
+    //  itemObject.insert("entryDateUTC", m_entryDateUTC.toString(Qt::ISODate));
+    itemObject.insert(TableModel::ROLE_NAMES.value(TableModel::NameRole),
+                      QString("Item %1").arg(row));
+    itemObject.insert(TableModel::ROLE_NAMES.value(TableModel::DescriptionRole),
+                      QString("This is item %1").arg(row));
+    itemObject.insert(TableModel::ROLE_NAMES.value(TableModel::InfoRole),
+                      QString("Info of item %1").arg(row));
+    itemObject.insert(TableModel::ROLE_NAMES.value(TableModel::AmountRole), row);
+    itemObject.insert(TableModel::ROLE_NAMES.value(TableModel::FactorRole), row * 1.1);
+
+    array.append(itemObject);
+  }
+  rootObject.insert("items", array);
+
+  doc.setObject(rootObject);
+  return doc.toJson();
+}
+
 TableModel::TableModel(QUndoStack* undoStack, QObject* parent)
     : QAbstractTableModel{parent}
-    , m_undoStack(undoStack) {
-  for (int row = 0; row < 5; ++row) {
-    QHash<int, QVariant> values;
-    values[NameRole]        = QString("Item %1").arg(row);
-    values[DescriptionRole] = QString("This is item %1").arg(row);
-    values[InfoRole]        = QString("Info of item %1").arg(row);
-    values[AmountRole]      = row;
-    values[FactorRole]      = row * 1.1;
-
-    shared_ptr<ModelItem> item = make_unique<ModelItem>(values);
-    m_items.append(std::move(item));
-  }
-}
+    , m_undoStack(undoStack) {}
 
 Qt::ItemFlags TableModel::flags(const QModelIndex& index) const {
   return Qt::ItemIsEditable | QAbstractTableModel::flags(index);
@@ -115,6 +129,21 @@ bool TableModel::setItemData(const QModelIndex& index, const QMap<int, QVariant>
   return false;
 }
 
+QJsonDocument TableModel::getAllItemsAsJsonDoc() const {
+  QJsonDocument doc = QJsonDocument();
+  QJsonObject rootObject;
+  QJsonArray array;
+
+  foreach (shared_ptr<ModelItem> item, m_items) {
+    QJsonObject itemObject = item->toJsonObject();
+    array.append(itemObject);
+  }
+  rootObject.insert("items", array);
+
+  doc.setObject(rootObject);
+  return doc;
+}
+
 bool TableModel::removeRows(int firstRow, int nRows, const QModelIndex& parentIndex) {
   if (parentIndex != QModelIndex()) {
     qWarning() << "Removing of child rows is not supported yet!";
@@ -147,7 +176,7 @@ void TableModel::insertItems(int startPosition,
     startPosition = m_items.size();
   }
 
-  QList<QHash<int, QVariant>> valueList = JsonParser::toItemValuesList(jsonDoc);
+  QList<QHash<int, QVariant>> valueList = JsonParser::toItemValuesList(jsonDoc, "items");
 
   InsertRowsCommand* insertCommand = new InsertRowsCommand(this, startPosition, valueList);
   m_undoStack->push(insertCommand);
@@ -245,18 +274,3 @@ bool TableModel::isEmptyValueEqualToZero(const int role) const {
   }
   return false;
 }
-
-QJsonDocument TableModel::getAllItemsAsJsonDoc() const {
-  QJsonDocument doc = QJsonDocument();
-  QJsonObject rootObject;
-  QJsonArray array;
-
-  foreach (shared_ptr<ModelItem> item, m_items) {
-    QJsonObject itemObject = item->toJsonObject();
-    array.append(itemObject);
-  }
-  rootObject.insert("items", array);
-
-  doc.setObject(rootObject);
-  return doc;
-}

model/tablemodel.h

@@ -19,6 +19,7 @@ class TableModel : public QAbstractTableModel {
   enum UserRoles { NameRole = Qt::UserRole + 1, DescriptionRole, InfoRole, AmountRole, FactorRole };
   static QHash<int, QByteArray> ROLE_NAMES;
   static QList<QString> intColumns;
+  static QByteArray generateExampleItems();
 
   explicit TableModel(QUndoStack* undoStack, QObject* parent = nullptr);
 
@@ -41,7 +42,9 @@ class TableModel : public QAbstractTableModel {
   // override;
   bool removeRows(int firstRow, int nRows, const QModelIndex& parentIndex = QModelIndex()) override;
   void appendItems(const QByteArray& jsonDoc);
-  void insertItems(int startPosition, const QByteArray& jsonDoc, const QModelIndex& parentIndex);
+  void insertItems(int startPosition,
+                   const QByteArray& jsonDoc,
+                   const QModelIndex& parentIndex = QModelIndex());
 
  private:
   /// *** members ***