QProcess not emitting any signals

Whuang

Hello,
I'm developing a GUI application that would execute an external command line executable. I have connected some of the signals to slots, but I find that none of the signals are emitting even though I see output from the "Application Output" window whilst debugging.

Here's some part of my code:

//MainWindowUi.h
private slots:
    void process_started();
    void process_output();
private:
    QProcess *process;

//MainWindowUi.cpp
MainWindowUi::MainWindowUi(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::BTDProgrammerUI)
{
    ui->setupUi(this);

    process = new QProcess(this);
    connect(process, SIGNAL(readyReadStandardOutput()), this, SLOT(process_output()));

}

void MainWindowUi::process_output()
{
    // Not executing here
    QByteArray processOutput;
    processOutput = process->readAllStandardOutput();
    qDebug() << QString(processOutput);
}

I've tried other signals (e.g. start/finished) but they aren't being emitted as well.

Any ideas where I went wrong?

Thanks

koahnig

@Whuang

I would not expect that startDetached can support all signals or if any at all.
You can even exit the calling program and the detached application with continue to run.

When you like to have signals transmitted you need to use start or the overloaded version.

Christian Ehrlicher

Where do you start your executable you want to start with QProcess?

Whuang

I started the process in a slot of a button's click signal

process->startDetached(exe, args);

koahnig

@Whuang

I would not expect that startDetached can support all signals or if any at all.
You can even exit the calling program and the detached application with continue to run.

When you like to have signals transmitted you need to use start or the overloaded version.

Whuang

@koahnig Thank you that was the reason why