how to import a file into qt when double clicking a file.

[berlinud]

I mean this:
If I have a program called A,and I set A as the default program for opening mp3 files in Linux,how can my program know it when the user opens a mp3 file in Linux desktop environment?

[Lykurg]

This has nothing to do with your application (Qt). It's a setting of your desktop environment and you have to set the setting there.

[Zlatomir]

@Lykurg: i think that what he meant to ask is: how the Linux OS is sending the file (name and path) to the associated qt application so that the programmer can open that particular file. (if that was the question - i don't know the answer )

[Lykurg]

@Lykurg: i think that what he meant to ask is: how the Linux OS is sending the file (name and path) to the associated qt application so that the programmer can open that particular file. (if that was the question - i don't know the answer )

Ok, if so, you have to parse the command line arguments in your main function and react on them. Normaly the file name is just append to the executable like: yourapp filename.mp3.

[tbscope]

Although suffixes will mostly do the job, a more correct way is to use mime types.

edit: ignore, I read the previous post wrong

[berlinud]

You are definitely right Zlatomir!
That is exactly what I mean.

[berlinud]

Would you mind explaining it a little more detail?
Since I am new in Linux programming.

[Zlatomir]

Ok, if so, you have to parse the command line arguments in your main function and react on them. Normaly the file name is just append to the executable like: yourapp filename.mp3.

I thought that might be the way, but i wasn't sure about that, thanks.

[berlinud]

what data will be transfered to me as the argument of main?
is that an absolute path?

[Lykurg]

is that an absolute path?

I don't know, and you also can't know. Your app has to check all possibilities. Simple have a look on the value of argv (e.g. using qDebug()) and try to determain how you can handle the parameters.

[Zlatomir]

Here is a test project:

#include <QtGui>
#include <QStringList>
 
int main(int argc, char** argv){
 
    QApplication a(argc, argv);
    QTextEdit t;
 
    QStringList l = qApp->arguments(); // qApp is a macro to QApplication instance and the arguments() returns a QStringList with the arguments 
 
    t.setText(l.join("\n"));
    t.show();
    return a.exec();
}

#include <QtGui>
#include <QStringList>

int main(int argc, char** argv){

    QApplication a(argc, argv);
    QTextEdit t;

    QStringList l = qApp->arguments(); // qApp is a macro to QApplication instance and the arguments() returns a QStringList with the arguments 

    t.setText(l.join("\n"));
    t.show();
    return a.exec();
}

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LE: I'm on win now and the first one is the full path and name of the application

[berlinud]

I tested it.
$ ./TestForMainArg ggg fff fff fff fff
the result is this:

./TestForMainArg
ggg
fff
fff
fff
fff

[Zlatomir]

create a text file rename it with .bla extension and create the association and see how the actual double click acts. (it should send the path too)

[berlinud]

When I turn the test program as the default program for mp3;
it shows that the arguments are transfered into the program as absolute path.

[berlinud]

yes you are right