[SOLVED] How to reuse QFile in multiple functions/methods

[fs_tigre]

Hi,

How can I make a QFile visible in multiple functions/methods? In other words I would like to create a QFile and be able to use the same name in multiple places, for instance the save and load functions.

I have tried...

.h
@private:
QFile myFile(QString);@

.cpp

@//constructor
myFile("/Users/userName/someFile.txt");@

later in the program

@if (myFile.open(QIODevice::WriteOnly))
...
@
Which of course doesn't work, I know this has to do with my poor understanding of the language C++.

Thanks a lot

[SGaist]

Hi,

did you check what error you have ?

[fs_tigre]

Error!
undefined reference to 'MainWindow::myFile(QString)

Is it even possible to have a QFile globally visible? Sorry if my original question doesn't make any sense I just don't like to be repeating the same code over an over.

I know I could use a string variable to hold the path and then just reuse the string but still doesn't feel right.

.h File
@#include <QFile>
QString fileName;@

.cpp File
@#include <QFile>
// cosntructor
fileName = "/Users/userName/someFile.txt";@

@// later in the program
QFile myFile(fileName);@

How do you guys usually do this?

[SGaist]

I just re-read your code

@
private:
QFile myFile(QString);
@

is not valid.

@
private:
QFile myFile;
@

is

and in your constructor:

@
myFile.setFileName("path_to_file");
@

EDIT: corrected sleepy head error

[fs_tigre]

First of all thank you for your reply.

When I do what you suggested I get the following message

'operator=' is a private member of 'QFile'

Any Idea what could be wrong?

@private:
QFile mainDataFile;@

@// constructor
mainDataFile = QFile("/Users/UserName/someFile.txt");@

@// later in the program
if (mainDataFile.open(QIODevice::WriteOnly))@

[dbzhang800]

@
MainWindow::MainWindow(...): mainDataFile (QFile("/Users/UserName/someFile.txt"))
{
}
@

or

@
mainDataFile.setFileName("/Users/UserName/someFile.txt");
@

[SGaist]

[quote author="1+1=2" date="1377656296"]@
MainWindow::MainWindow(...): mainDataFile (QFile("/Users/UserName/someFile.txt"))
{
}
@
[/quote]

won't work either, the copy constructor as well as the assignment operator are private (QFile's a QObject)

[fs_tigre]

@private:
QFile myFile;@
@// Constructor
myFile.setFileName("path_to_file");@

This works, thanks a lot for your help.

[SGaist]

You're welcome !

Please update the thread's title prepending solved so other forum users may know an answer has been found :)