Qt 5.6 | Qt Widgets | Part 6 - Loading and Saving | addressbook.cpp Example File

Qt 5.6.2 Reference Documentation

# addressbook.cpp Example File

tutorials/addressbook/part6/addressbook.cpp

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      #include <QtWidgets>
      #include "addressbook.h"

      AddressBook::AddressBook(QWidget *parent)
          : QWidget(parent)
      {
          QLabel *nameLabel = new QLabel(tr("Name:"));
          nameLine = new QLineEdit;
          nameLine->setReadOnly(true);

          QLabel *addressLabel = new QLabel(tr("Address:"));
          addressText = new QTextEdit;
          addressText->setReadOnly(true);

          addButton = new QPushButton(tr("&Add"));

          editButton = new QPushButton(tr("&Edit"));
          editButton->setEnabled(false);
          removeButton = new QPushButton(tr("&Remove"));
          removeButton->setEnabled(false);
          findButton = new QPushButton(tr("&Find"));
          findButton->setEnabled(false);
          submitButton = new QPushButton(tr("&Submit"));
          submitButton->hide();
          cancelButton = new QPushButton(tr("&Cancel"));
          cancelButton->hide();

          nextButton = new QPushButton(tr("&Next"));
          nextButton->setEnabled(false);
          previousButton = new QPushButton(tr("&Previous"));
          previousButton->setEnabled(false);

          loadButton = new QPushButton(tr("&Load..."));
          loadButton->setToolTip(tr("Load contacts from a file"));
          saveButton = new QPushButton(tr("&Save..."));
          saveButton->setToolTip(tr("Save contacts to a file"));
          saveButton->setEnabled(false);

          dialog = new FindDialog(this);

          connect(addButton, SIGNAL(clicked()), this, SLOT(addContact()));
          connect(submitButton, SIGNAL(clicked()), this, SLOT(submitContact()));
          connect(editButton, SIGNAL(clicked()), this, SLOT(editContact()));
          connect(cancelButton, SIGNAL(clicked()), this, SLOT(cancel()));
          connect(removeButton, SIGNAL(clicked()), this, SLOT(removeContact()));
          connect(findButton, SIGNAL(clicked()), this, SLOT(findContact()));
          connect(nextButton, SIGNAL(clicked()), this, SLOT(next()));
          connect(previousButton, SIGNAL(clicked()), this, SLOT(previous()));
          connect(loadButton, SIGNAL(clicked()), this, SLOT(loadFromFile()));
          connect(saveButton, SIGNAL(clicked()), this, SLOT(saveToFile()));

          QVBoxLayout *buttonLayout1 = new QVBoxLayout;
          buttonLayout1->addWidget(addButton);
          buttonLayout1->addWidget(editButton);
          buttonLayout1->addWidget(removeButton);
          buttonLayout1->addWidget(findButton);
          buttonLayout1->addWidget(submitButton);
          buttonLayout1->addWidget(cancelButton);
          buttonLayout1->addWidget(loadButton);
          buttonLayout1->addWidget(saveButton);
          buttonLayout1->addStretch();

          QHBoxLayout *buttonLayout2 = new QHBoxLayout;
          buttonLayout2->addWidget(previousButton);
          buttonLayout2->addWidget(nextButton);

          QGridLayout *mainLayout = new QGridLayout;
          mainLayout->addWidget(nameLabel, 0, 0);
          mainLayout->addWidget(nameLine, 0, 1);
          mainLayout->addWidget(addressLabel, 1, 0, Qt::AlignTop);
          mainLayout->addWidget(addressText, 1, 1);
          mainLayout->addLayout(buttonLayout1, 1, 2);
          mainLayout->addLayout(buttonLayout2, 2, 1);

          setLayout(mainLayout);
          setWindowTitle(tr("Simple Address Book"));
      }

      void AddressBook::addContact()
      {
          oldName = nameLine->text();
          oldAddress = addressText->toPlainText();

          nameLine->clear();
          addressText->clear();

          updateInterface(AddingMode);
      }

      void AddressBook::editContact()
      {
          oldName = nameLine->text();
          oldAddress = addressText->toPlainText();

          updateInterface(EditingMode);
      }

      void AddressBook::submitContact()
      {
          QString name = nameLine->text();
          QString address = addressText->toPlainText();

          if (name.isEmpty() || address.isEmpty()) {
              QMessageBox::information(this, tr("Empty Field"),
                  tr("Please enter a name and address."));
              return;
          }

          if (currentMode == AddingMode) {

              if (!contacts.contains(name)) {
                  contacts.insert(name, address);
                  QMessageBox::information(this, tr("Add Successful"),
                      tr("\"%1\" has been added to your address book.").arg(name));
              } else {
                  QMessageBox::information(this, tr("Add Unsuccessful"),
                      tr("Sorry, \"%1\" is already in your address book.").arg(name));
              }
          } else if (currentMode == EditingMode) {

              if (oldName != name) {
                  if (!contacts.contains(name)) {
                      QMessageBox::information(this, tr("Edit Successful"),
                          tr("\"%1\" has been edited in your address book.").arg(oldName));
                      contacts.remove(oldName);
                      contacts.insert(name, address);
                  } else {
                      QMessageBox::information(this, tr("Edit Unsuccessful"),
                          tr("Sorry, \"%1\" is already in your address book.").arg(name));
                  }
              } else if (oldAddress != address) {
                  QMessageBox::information(this, tr("Edit Successful"),
                      tr("\"%1\" has been edited in your address book.").arg(name));
                  contacts[name] = address;
              }
          }

          updateInterface(NavigationMode);
      }

      void AddressBook::cancel()
      {
          nameLine->setText(oldName);
          addressText->setText(oldAddress);
          updateInterface(NavigationMode);
      }

      void AddressBook::removeContact()
      {
          QString name = nameLine->text();
          QString address = addressText->toPlainText();

          if (contacts.contains(name)) {

              int button = QMessageBox::question(this,
                  tr("Confirm Remove"),
                  tr("Are you sure you want to remove \"%1\"?").arg(name),
                  QMessageBox::Yes | QMessageBox::No);

              if (button == QMessageBox::Yes) {

                  previous();
                  contacts.remove(name);

                  QMessageBox::information(this, tr("Remove Successful"),
                      tr("\"%1\" has been removed from your address book.").arg(name));
              }
          }

          updateInterface(NavigationMode);
      }

      void AddressBook::next()
      {
          QString name = nameLine->text();
          QMap<QString, QString>::iterator i = contacts.find(name);

          if (i != contacts.end())
              i++;

          if (i == contacts.end())
              i = contacts.begin();

          nameLine->setText(i.key());
          addressText->setText(i.value());
      }

      void AddressBook::previous()
      {
          QString name = nameLine->text();
          QMap<QString, QString>::iterator i = contacts.find(name);

          if (i == contacts.end()) {
              nameLine->clear();
              addressText->clear();
              return;
          }

          if (i == contacts.begin())
              i = contacts.end();

          i--;
          nameLine->setText(i.key());
          addressText->setText(i.value());
      }

      void AddressBook::findContact()
      {
          dialog->show();

          if (dialog->exec() == 1) {
              QString contactName = dialog->getFindText();

              if (contacts.contains(contactName)) {
                  nameLine->setText(contactName);
                  addressText->setText(contacts.value(contactName));
              } else {
                  QMessageBox::information(this, tr("Contact Not Found"),
                      tr("Sorry, \"%1\" is not in your address book.").arg(contactName));
                  return;
              }
          }

          updateInterface(NavigationMode);
      }

      void AddressBook::updateInterface(Mode mode)
      {
          currentMode = mode;

          switch (currentMode) {

          case AddingMode:
          case EditingMode:

              nameLine->setReadOnly(false);
              nameLine->setFocus(Qt::OtherFocusReason);
              addressText->setReadOnly(false);

              addButton->setEnabled(false);
              editButton->setEnabled(false);
              removeButton->setEnabled(false);

              nextButton->setEnabled(false);
              previousButton->setEnabled(false);

              submitButton->show();
              cancelButton->show();

              loadButton->setEnabled(false);
              saveButton->setEnabled(false);
              break;

          case NavigationMode:

              if (contacts.isEmpty()) {
                  nameLine->clear();
                  addressText->clear();
              }

              nameLine->setReadOnly(true);
              addressText->setReadOnly(true);
              addButton->setEnabled(true);

              int number = contacts.size();
              editButton->setEnabled(number >= 1);
              removeButton->setEnabled(number >= 1);
              findButton->setEnabled(number > 2);
              nextButton->setEnabled(number > 1);
              previousButton->setEnabled(number > 1);

              submitButton->hide();
              cancelButton->hide();

              loadButton->setEnabled(true);
              saveButton->setEnabled(number >= 1);
              break;
          }
      }

      void AddressBook::saveToFile()
      {
          QString fileName = QFileDialog::getSaveFileName(this,
              tr("Save Address Book"), "",
              tr("Address Book (*.abk);;All Files (*)"));

          if (fileName.isEmpty())
              return;
          else {
              QFile file(fileName);
              if (!file.open(QIODevice::WriteOnly)) {
                  QMessageBox::information(this, tr("Unable to open file"),
                      file.errorString());
                  return;
              }

              QDataStream out(&file);
              out.setVersion(QDataStream::Qt_4_5);
              out << contacts;
          }
      }

      void AddressBook::loadFromFile()
      {
          QString fileName = QFileDialog::getOpenFileName(this,
              tr("Open Address Book"), "",
              tr("Address Book (*.abk);;All Files (*)"));

          if (fileName.isEmpty())
              return;
          else {

              QFile file(fileName);

              if (!file.open(QIODevice::ReadOnly)) {
                  QMessageBox::information(this, tr("Unable to open file"),
                      file.errorString());
                  return;
              }

              QDataStream in(&file);
              in.setVersion(QDataStream::Qt_4_5);
              contacts.clear();   // clear existing contacts
              in >> contacts;

              if (contacts.isEmpty()) {
                  QMessageBox::information(this, tr("No contacts in file"),
                      tr("The file you are attempting to open contains no contacts."));
              } else {
                  QMap<QString, QString>::iterator i = contacts.begin();
                  nameLine->setText(i.key());
                  addressText->setText(i.value());
              }
          }

          updateInterface(NavigationMode);
      }