Using JumpList to store files opened in the application when using Qt

winExtras, jumpList

JumpList, one of the features that are present only in Windows (version 7 and above). In this sheet, in particular, you can store links to the most recently opened files in the application.

Step-by-step instruction

To use this function, you need to

Connect the module

QT += winextras

Connect library

#include <QtWinExtras>

Make the appropriate JumpList section active

QWinJumpList jumplist;
jumplist.recent()->setVisible(true);

Associate all the required file extensions with our application using the function

static void associateFileTypes(const QStringList &fileTypes)
{
    QString displayName = QGuiApplication::applicationDisplayName();
    QString filePath = QCoreApplication::applicationFilePath();
    QString fileName = QFileInfo(filePath).fileName();
    QSettings settings("HKEY_CURRENT_USER\\Software\\Classes\\Applications\\" + fileName, QSettings::NativeFormat);
    settings.setValue("FriendlyAppName", displayName);
    settings.beginGroup("SupportedTypes");
    foreach (const QString& fileType, fileTypes)
        settings.setValue(fileType, QString());
    settings.endGroup();
    settings.beginGroup("shell");
    settings.beginGroup("open");
    settings.setValue("FriendlyAppName", displayName);
    settings.beginGroup("Command");
    settings.setValue(".", QChar('"') + QDir::toNativeSeparators(filePath) + QString("\" \"%1\""));
}

Which is convenient to use in the main

QApplication a(argc, argv);
a.setApplicationDisplayName("QtWinExtras Test");
associateFileTypes(QStringList(".txt"));

Now when you open a new file, a link to it will be added to the last JumpList section.

When clicking on one of the links that appears, our application will start with the file name as the second parameter (argv [1]). With such a configuration, it is reasonable to modify the main function so that the selected file is opened.

if(argc == 2)
        w.open(QString::fromLocal8Bit(argv[1]).replace(QString("\\"),QString("/")));

It is also possible to implement when, when the application is started, it is checked if there is a copy of it running. If such a copy is found, the application will send the name of the selected file to it and finish its work. I wrote the following implementation, where the name of the file is written to the registry.

    HANDLE hCorvetEvent = CreateEventA(NULL, FALSE, FALSE, ("winExJumpList"));
    if (GetLastError() ==  ERROR_ALREADY_EXISTS)
    {
        if(argc == 2)
        {
            QSettings *settings;
            settings = new QSettings("Company", "my programm");
            settings->setValue("AddFile", QString::fromLocal8Bit(argv[1]).replace(QString("\\"),QString("/") ) ); 
           CloseHandle(hCorvetEvent);
        }
        return 0;
    }

The program uses a timer-based function to monitor the registry change and open the added file.

connect(ui->pushButton, &QPushButton::clicked, this, &MainWindow::openFile);
    QTimer *openFile = new QTimer;
    connect(openFile, &QTimer::timeout, this, &MainWindow::nextFile);
    openFile->start(500);
void MainWindow::nextFile()
{
    QSettings *settings;
    settings = new QSettings("Company", "my programm");
    QString s = settings->value("AddFile").toString();
    if(!s.isEmpty())
    {
        settings->setValue("AddFile", "");
        open(s);
    }
}

Of course, you will see the work of the program after you add the libraries necessary for the snack to the compiled exe-file.

Project with the source code of the program