I want to block my program until finishing the download !

[bluemmb]

Hi . I am new in QT and I wrote a code for download file using QNetworkAccessManager , but I want to block my code until the download finishs.

this is my main :

int main(int argc, char *argv[])
{
    QCoreApplication app(argc, argv);
    MyClass* obj = new MyClass();

    obj->downloadToQString(QUrl( "http://codeforces.com" ));
    if ( obj->error == false )
        qDebug() << obj->result;
    else
        qDebug() << "Error : " <<obj->errorString;

    app.exec();
}

my request for download :

void downloadToQString(QUrl url)
    {
        error = false;
        errorString = "";
        result = "";

        reply = nam.get(QNetworkRequest(url));
        QObject::connect(reply, SIGNAL(finished()), this, SLOT(onFinishedQString()));
    }

because download don't make block the program , it continues it's running and main prints empty string in output.

I know Threading is good but it will be hard for me to handle it.

[mistralegna]

Hello,

In your method downloadToQString, you connect your QNetworkReply* to a slot of your class MyClass. Why don't you print the result in this method ?

[bluemmb]

@mistralegna Hi . I wrote this code just for testing downloading does work correctly or not.

I will use this class in GUI project not in console. first I must prevent user from doing anything before download completes and after knowing the result of download , decide what i have to do.

[bluemmb]

@bluemmb sorry I mean Widget Application.

[raven-worx]

@bluemmb
Basically this is possible (e.g. using a "local" QEventLoop), but since you mentioned that you want to use it in GUI it would be way better usability/UX design if you show for example a modal dialog as long as the download isn't finished.

You could use a QProgressDialog or even a custom QDialog subclass and set them modal. So the user knows that something is going on instead of a simply unresponding application.

[bluemmb]

@raven-worx thanks , i have been doing what you have told.
But i really want to know how we can do it , is there any way at all ?

[raven-worx]

@bluemmb

QNetworkReply* reply = nam->get( request )  ;

QEventLoop loop;
connect(reply, SIGNAL(finished()), &loop, SLOT(quit()));
loop.exec();

[bluemmb]

@bluemmb thanks very much , i used your code in another place :)