my application doesnt work:( can you help me to understand why?

[RuWex]

@jsulm @jsulm
mainwind->writeData(file);

its not sent it to terminal and writedata()- this function work(I use it in other situation and it workes well)

[jsulm]

@RuWex What about adding error handling? A proper application should have it.
For example: m_serial->write(data) has a return value with a meaning, you simply ignore it. And there is also https://doc.qt.io/qt-5/qserialport.html#error-prop
Then you're blocking Qt event loop with your QThread::sleep(1), this can also break things.

Why do you send these strings character by character instead whole string at once?

[RuWex]

@jsulm
-Why do you send these strings character by character instead whole string at once?

because I have to make timer between any char,
the camera need to get the command character by character with waiting between

[jsulm]

@RuWex said in my application doesnt work:( can you help me to understand why?:

the camera need to get the command character by character with waiting between

Then you should rework your code. You should use a QTimer and on each timeout send next character. With your current approach you're blocking the event loop.
And don't forget to add error handling...

[RuWex]

@jsulm
I did it,
before I load the code I took away all unrelevant line:

void SendCommands::StartToSendCommand( QString fileName)//Ruth
{

    bool ans=additionalTest->CountsTheTimeRemaining(fileName);
    if (ans)
    {
        QFile file(fileName);
        if (!file.open(QIODevice::ReadOnly | QIODevice::Text))
            return;


        QTextStream in(&file);
        QString line;
        while (!in.atEnd()) {

            line = in.readLine();
            if (line==""||line[0]=="#")
                continue;
   
            for(int i=0; i< line.length(); ++i)
            {
                QString letter= (QString)line[i];
                MainSendCommand mainSend(letter.toLatin1());
                mainSend.ActivationMainWindow();
                QThread::sleep(1);

            }
            qDebug()<<endl;
            timer->start(GWaitingTimeBetweenCommand);
            QApplication::processEvents();
            QThread::sleep(2);

        }

    }
    else {
        return;
    }

}

[jsulm]

@RuWex said in my application doesnt work:( can you help me to understand why?:

I did it,

What?
QTimer to send characters? No, you did not!
You start a timer after sending all the characters in the for loop...

[JonB]

@RuWex said in my application doesnt work:( can you help me to understand why?:

        QThread::sleep(1);
        QApplication::processEvents();
        QThread::sleep(2);

And in addition to @jsulm none of the above lines should be in your code any longer (when you get the timer right).

[RuWex]

@RuWex said in my application doesnt work:( can you help me to understand why?:

timer->start(GWaitingTimeBetweenCommand);

I did it in the constructor:

SendCommands::SendCommands()
{
    additionalTest= new DoAdditionalTest();
    timer= new QTimer();
}

void SendCommands::StartToSendCommand( QString fileName)//Ruth
{

bool ans=additionalTest->CountsTheTimeRemaining(fileName);
if (ans)
{
    QFile file(fileName);
    if (!file.open(QIODevice::ReadOnly | QIODevice::Text))
        return;


    QTextStream in(&file);
    QString line;
    while (!in.atEnd()) {

        line = in.readLine();
        if (line==""||line[0]=="#")
            continue;

        for(int i=0; i< line.length(); ++i)
        {
            QString letter= (QString)line[i];
            MainSendCommand mainSend(letter.toLatin1());
            mainSend.ActivationMainWindow();
            QThread::sleep(1);

        }
        qDebug()<<endl;
        **~~timer->start(GWaitingTimeBetweenCommand);~~**
        QApplication::processEvents();
        QThread::sleep(2);

    }

}
else {
    return;
}

}

[RuWex]

@jsulm @JonB I dont understand what is my problem
can you explain me how to change the code and where?

[JonB]

@RuWex
Please look at the QTimer documentation, and the examples there. This does not work by "inserting a delay" into the code where it is called. Rather, it sets off a timer which keeps running, and you supply a "slot"/"callback" which will be invoked when the timer expires. It is in that function/lambda that you do whatever work you wish to perform each time the repeating or singleshot timer expires, e.g. in your case maybe it sends the next character.