I am a newbie in qt development and i want to transfer the output of QProcess to a textBrowser in real time. I started by executing a simple echo command,but the output of the program is not getting displayed. What am i doing wrong????
QProcess p;
p.start("echo hye");
QByteArray byteArray = p.readAllStandardOutput();
QStringList strLines = QString(byteArray).split("\n");
QString line= p.readAllStandardOutput();
if(p.state()==QProcess::NotRunning)
ui->textBrowser->append("not running");
foreach (QString line, strLines){
ui->textBrowser->append(line);}
P.S. I am on a linux machine.
EDIT: I am still not able to get the output in a textBrowser .
I changed the Qprocess parameters and tried both waitForStarted() and waitForReadyRead() so that the process starts in time and the results are available.
I added waitForFinished() so that the process does not terminate when it goes out of scope.
QProcess p;
p.start("echo", QStringList() << "hye");
p.waitForStarted();
QByteArray byteArray = p.readAllStandardOutput();
QStringList strLines = QString(byteArray).split("\n");
QString line= p.readAllStandardOutput();
if(p.state()==QProcess::NotRunning)
ui->textBrowser->append("not running");
ui->textBrowser->append(line);
p.waitForFinished();
to read standard output you need to either call waitForReadyRead()
before reading stardard output , or you need to connect Qprocess's signal readyReadStandardOutput()
to your slot and read standard output from slot.
also make sure that your QProcess is not on stack.
I tried following code works fine.
EDIT:
MyProcess::MyProcess(QObject *parent) :
QObject(parent)
{
QString program = "echo";
QStringList arguments;
arguments << "Hello";
mProcess.start(program,arguments);
connect(&mProcess,SIGNAL(readyReadStandardOutput()),this,SLOT(readyReadStandardOutput()));
connect(&mProcess,SIGNAL(readyReadStandardError()),this,SLOT(readyReadStandardError()));
}
void MyProcess::readyReadStandardOutput(){
qDebug()<< mProcess.readAllStandardOutput();
}
void MyProcess::readyReadStandardError(){
qDebug() << mProcess.readAllStandardError();
}
来源:https://stackoverflow.com/questions/10098980/real-time-display-of-qprocess-output-in-a-textbrowser