text: #ifndef ELECTRONICSMAINWINDOW_H
  #define ELECTRONICSMAINWINDOW_H
  
  #include <QMainWindow>
  #include <QIcon>
  #include <QWebView>
  #include <QString>
  #include <QStringList>
  #include <QListWidget>
  #include <QListWidgetItem>
  #include <QDebug>
  #include <QPair>
  #include <QMap>
  #include <QMessageBox>
  #include <QWebSettings>
  #include <QWidget>
  #include <QTimer>
  #include <QPropertyAnimation>
  #include <QPixmap>
  #include <QFontDialog>
  #include <QTreeWidgetItem>
  #include <QTreeWidgetItemIterator>
  
  #define DEFAULT_TREE_COLUMN 0
  #define DEFAULT_INDEX 0
  
  namespace Ui {
  class ElectronicsMainWindow;
  }
  
  class ElectronicsMainWindow : public QMainWindow
  {
      Q_OBJECT
  
  public:
      explicit ElectronicsMainWindow(QWidget *parent = 0);
      void loadListDefaultItems();
      void loadTopicLink();
      QString linkMaker(QString);
      ~ElectronicsMainWindow();
  
  public slots:
  
      void on_moreButton_toggled(bool checked);
      void findTopic(QString the_topic);
      void updateIndexList(QStringList list);
      void on_indexTreeWidget_itemClicked(QTreeWidgetItem *item, int column);
      void loadLink(int);
  
      void on_indexListWidget_itemClicked(QListWidgetItem *item);
  
      void on_fontButton_clicked();
  
  
      void loadTheUrl(QUrl);
  
  
  
  signals:
      void passFoundTopicList(QStringList topic_list);
      void passKey(int);
      void loadUrl(QUrl);
  
  private:
      Ui::ElectronicsMainWindow *ui;
      static const QString file_initial;
      static const QString html;
      QFont font;
  
      QList<QListWidgetItem *> found_items;
      QStringList found_item_name;
      QStringList topic_lists;
      QStringList topic_links;
      QList <QPair <QString, QString> > topic_name_link;
      QMap < int, QPair <QString, QString> > topic_name_link_map;
  };
  
  #endif // ELECTRONICSMAINWINDOW_H
  