How do I run an exe file on button clicked in a Qt app?

S.ARE

I have a set of console applications that I made in Visual Studio.

Now, instead of going folder by folder to open each of those console applications, I want to lay them out so they will look neat. To lay them out, of course, is to make a Qt program that has buttons on it that I, the user, will press in order to execute my desired console application.

The console applications are in .exe files and when I open them, they work. However, with Qt, I don't seem to make it work.

First, I tried system("../myapp.exe"), but it is not really a good choice. It opens up a new window, i.e. cmd, and my program works there, however, as long as that cmd window is open, it won't let me interact with Qt app.

I don't feel comfortable using system() so I searched the internet for other options.
So, I found QProcess and I tried to use it, like this:

QProcess *process = new QProcess(this);
QString file("\".../myapp.exe\"");
process->execute(file);

The console application works but only inside the debug window of Qt and it won't let me do any kind of inputs.

What I want is a new window, which is a cmd window, to pop-up. And also I want to be able to interact too with the Qt app.

Please help, thanks in advance.

Gojir4

@S.ARE Hi,
You probably want to use QProcess::startDetached().
Arguments are optional of course.

QProcess::startDetached("myexe", QStringList() << "any_argument");

S.ARE

@Gojir4 Thank you but,

Care to explain how to use it? As you can see, I'm still a beginner. :)

Oops, sorry, I didn't see the example.

S.ARE

@Gojir4 said in How do I run an exe file on button clicked in a Qt app?:

QStringList() << "any_argument"

I tried the code and it works, however, it didn't open any window.
What's the problem?

EDIT:
I thought of a way of handling this problem.
I created a batch file with this code in it:

cd %~dp0
start file.exe

And with that batch file, I accessed it in Qt by the code you told me:

QProcess::startDetached("\".../test.bat\"");

And it worked as I wanted it to be.
Though, if possible, I want to know how to open another cmd window using Qt instead of using
a batch file.

Anyway, thanks.

sierdzio

@S.ARE said in How do I run an exe file on button clicked in a Qt app?:

QProcess::startDetached("".../test.bat"");

Note that you don't need to escape anything here, and there is no reason to use Windows path syntax. Qt understands (and automatically handles) unix-style paths on all platforms. So:

QProcess::startDetached("../test.bat");

is enough. Just be careful with such relative paths - that code won't work if you run it from some different directory (where test is not in the parent dir). If you want a more foolproof solution, chuck app dir in there:

QProcess::startDetached(QCoreApplication::instance()->applicationDirPath() + "/../test.bat");

Lastly, if you want to open some file using default app used for such files on given platform, you can use QDesktopServices::openUrl(). It's probably not necessary in this case, however.

JonB

@S.ARE
Still not 100% on what you want. You seem to be getting somewhere with @sierdzio's startDetached().

cd %~dp0
start file.exe

Though, if possible, I want to know how to open another cmd window using Qt instead of using
a batch file.

You should be able to achieve this directly, if that's what you want, via

QProcess::startDetached("cmd /k myapp.exe");

which will keep the opened terminal/console around after your app runs, not sure if that's what you mean.

If you need a cd to set the working directory, you can use the overload http://doc.qt.io/qt-5/qprocess.html#startDetached-1 :
bool QProcess::startDetached(const QString &program, const QStringList &arguments, const QString &workingDirectory = QString(), qint64 *pid = nullptr)

Does any of that get you closer to what you want?

S.ARE

@sierdzio I don't know why but the file won't start without the escape sequences.
And, I already implemented that code:

QProcess::startDetached(QCoreApplication::instance()->applicationDirPath() + "/../test.bat");

Anyway, thanks for helping out.

S.ARE

@JonB
I tried your code, however, it didn't open a new cmd window. (The console application ran on the debug window, i.e. the "Application Output" tab.)

About the ...

bool QProcess::startDetached(const QString &program, const QStringList &arguments, const QString &workingDirectory = QString(), qint64 *pid = nullptr)

I don't seem to understand how to use it.

Anyway, what I did is...

QString program("cmd /k cd " + QCoreApplication::applicationDirPath() + " & file.exe");
QProcess::startDetached(program);

jsulm

@S.ARE Do not put parameters into same string as program:

QString program("cmd.exe");
QStringList parameters;
parameters << " /k" << "cd " << QCoreApplication::applicationDirPath() << " & file.exe");
QProcess::startDetached(program, parameters);
``

xkungfu

@S-ARE said in How do I run an exe file on button clicked in a Qt app?:

cd %~dp0
start file.exe

AWESOME SOLUTION. THE NEW PROCESS WON'T BLOCK MAIN PROCESS, AND ALSO OUTPUT TO THE CMD WINDOW.
ONE STEP , MULTI TARGET。MANY BIRDS WITH ONE STONE~