How to detect a QProcess is started

[cooler123]

I start the process A before my main application starts using startDetached of QProcess.
However I having problem of the main application lose focus to process A.
I have try to set back focus to main application, however the process A is actually show up slower than the main application. So, my code of set focus will finish run even before process A runs finished and get the focus.

How to actually detect when process A is started? When process A start up it only shows as system tray icon.

[^NyAw^]

Hi,

Take a look at QProcess::finished signal

[cooler123]

Oops, my mistake.
I actually need to know when the process A actually started and not finished running.

[mazurekwrc]

maybe stateChanged ( QProcess::ProcessState newState ) signal will help you ?

[cooler123]

I use startDetached to start the process that will not affect my main application.
I have try all the signal, started, finished, stateChanged... all also not working. No signal is returned.

[jacek]

I use startDetached to start the process that will not affect my main application.
I have try all the signal, started, finished, stateChanged... all also not working. No signal is returned.

QProcess::startDetached() is a static method, so there is no QProcess object you can connect to to receive the signal from. Use QProcess::start() instead.

[cooler123]

After i use start() to start the process, can I detached it after that?

[jacek]

After i use start() to start the process, can I detached it after that?

No, you can't. QProcess will kill its child processes. Maybe you could someway determine the state of child process if you had its PID?

[The Storm]

Why you need to detach the child process? If you don't call the waitForFinished() function the child process will not block your application and you will be able to monitor it well.

[mcosta]

The QProcess:startDetached function returns TRUE on success and set pid argument