Qt 5.9 | Qt Quick Controls 2 | Qt Quick Controls 2 - Chat Tutorial | sqlcontactmodel.cpp Example File

Qt 5.9.2 Reference Documentation

# sqlcontactmodel.cpp Example File

chattutorial/chapter4-models/sqlcontactmodel.cpp

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      #include "sqlcontactmodel.h"

      #include <QDebug>
      #include <QSqlError>
      #include <QSqlQuery>

      static void createTable()
      {
          if (QSqlDatabase::database().tables().contains(QStringLiteral("Contacts"))) {
              // The table already exists; we don't need to do anything.
              return;
          }

          QSqlQuery query;
          if (!query.exec(
              "CREATE TABLE IF NOT EXISTS 'Contacts' ("
              "   'name' TEXT NOT NULL,"
              "   PRIMARY KEY(name)"
              ")")) {
              qFatal("Failed to query database: %s", qPrintable(query.lastError().text()));
          }

          query.exec("INSERT INTO Contacts VALUES('Albert Einstein')");
          query.exec("INSERT INTO Contacts VALUES('Ernest Hemingway')");
          query.exec("INSERT INTO Contacts VALUES('Hans Gude')");
      }

      SqlContactModel::SqlContactModel(QObject *parent) :
          QSqlQueryModel(parent)
      {
          createTable();

          QSqlQuery query;
          if (!query.exec("SELECT * FROM Contacts"))
              qFatal("Contacts SELECT query failed: %s", qPrintable(query.lastError().text()));

          setQuery(query);
          if (lastError().isValid())
              qFatal("Cannot set query on SqlContactModel: %s", qPrintable(lastError().text()));
      }