Open file in already open App

Sikarjan

Hi,

I am working on a tabbed code editor. I managed to associate a file type with my app but when I double click a second file the app started again. The idea was that the second file would be opened in the already open app as a second tab.

This is my main.cpp. How can I modify it so that no duplicates of this app are started?

#include "mainwindow.h"
#include <QApplication>

int main(int argc, char *argv[])
{
    Q_INIT_RESOURCE(qrc);

    QApplication app(argc, argv);
    app.setStyleSheet("QSplitter::handle { background-color: #999999 }");

    QCoreApplication::setOrganizationName("innoBiz");
    QCoreApplication::setApplicationName("phpPad");
    QCoreApplication::setApplicationVersion(QT_VERSION_STR);
    QCommandLineParser parser;
    parser.setApplicationDescription(QCoreApplication::applicationName());
    parser.addHelpOption();
    parser.addVersionOption();
    parser.addPositionalArgument("file", "The file to open.");
    parser.process(app);

    MainWindow mainWin;
    if (!parser.positionalArguments().isEmpty()){
        QString path = parser.positionalArguments().first();
        path.replace(QString("\\"), QString("/"));
        mainWin.addEditor(path);
    }
    mainWin.show();

    return app.exec();
}

I copied this code from the Application Example. Actually I do not really understand how this parser thing works...

Thanks for any help.

jsulm

@Sikarjan Maybe this is of interest: https://github.com/qtproject/qt-solutions/tree/master/qtsingleapplication

Sikarjan

Thanks for the link. I guess that is what I need.

SGaist

Hi,

While the suggestion is correct, you should rather use http://code.qt.io/cgit/qt-solutions/qt-solutions.git/ which is the official repository. Github is just a mirror.

Sikarjan

If been trying to get the qtsingleapplication class to work with no success. Is there another option out there, which is easier to implement?

Sikarjan

I got the qtsingleapplicaiton "plugin" to work. My main.cpp looks like this now:

#include "mainwindow.h"
#include <QApplication>
#include <qtsingleapplication.h>

int main(int argc, char *argv[])
{
    Q_INIT_RESOURCE(qrc);

    QtSingleApplication app(argc, argv);

    if (app.isRunning()){
        QString message;
        for (int a = 1; a < argc; ++a) {
            message += argv[a];

        if (a < argc-1)
            message += " ";
        }

        return !app.sendMessage(message);
    }

    app.setStyleSheet("QSplitter::handle { background-color: #999999 }");

    QCoreApplication::setOrganizationName("innoBiz");
    QCoreApplication::setApplicationName("phpPad");
    QCoreApplication::setApplicationVersion(QT_VERSION_STR);
    QCommandLineParser parser;
    parser.setApplicationDescription(QCoreApplication::applicationName());
    parser.addHelpOption();
    parser.addVersionOption();
    parser.addPositionalArgument("file", "The file to open.");
    parser.process(app);

    MainWindow mainWin;
    app.setActivationWindow(&mainWin);
    if (!parser.positionalArguments().isEmpty()){
        QStringList files = parser.positionalArguments();
        foreach(QString path, files){
            path.replace(QString("\\"), QString("/"));
            mainWin.addEditor(path);
        }
    }
    mainWin.show();

    QObject::connect(&app, SIGNAL(messageReceived(const QString&)), &mainWin,SLOT(handleAppOpenMessage(const QString&)));

    return app.exec();
}

In my MainWindow I added the slot handleAppOpenMessage(QString message) which does the same as the for each loop above

message.replace(QString("\\"), QString("/"));
addEditor(path);

This is probably not a very nice bit of code but currently is is working on Windows. If someone likes to make a suggestion on how to do this better, I am open to feedback.

I believe the for loop to build the message is not required. If I try to open e.g. three files on windows three messages are send and not one with three files.

SGaist

You can use QDir::fromNativeSeparators to convert your paths.