QSettings

I am using :

Code:

---

settings.value( "coco", "ERROR" ).toString();

---

this works

Code:

---

const QString s = "coco";
settings.value( s, "ERROR" ).toString();

---

this insists on returning "ERROR"

Is there a way to pass a variable to settings.value ?

s being a const string

You can't change the value of const variables; that's why the compiler won't let you do:
s = "asdf";

But you can just remove the const for your s variable, since you always can pass non-const variables into functions that take const variables. The const just means that the function won't (and shouldn't) change the value of the variable passed in.

QString s = "coco";
s = "asdf";
settings.value( s, "ERROR" ).toString();

Is this what you are asking?

Code:

---

QString x = "TxtCharSMSMax";
  qS = settings.value( x, "ERROR" ).toString();

---

Despite the fact that "TxtCharSMSMax" is a valid key, settings.value does not accept it.
It seems it takes only settings.value("something") and nothing else than quoted values.

Can't find a way to pass a value.

Weird. What's the exact text message of the error message from the compiler? Are you using Visual C++ or MinGW?

Quote:

---

Originally Posted by incapacitant

I am using :

Code:

---

settings.value( "coco", "ERROR" ).toString();

---

this works

Code:

---

const QString s = "coco";
settings.value( s, "ERROR" ).toString();

---

this insists on returning "ERROR"

Is there a way to pass a variable to settings.value ?

s being a const string

---

const QString works for me on (Qt 4.1.3 / WindowsXP / Visual Studio 2005) and (Qt 4.0.1 / WindowsXP / mingw - g++)

Here is the code:

Code:

---

#include <QString>
#include <QSettings>
#include <iostream>
 
int main(int argc, char *argv[])
{
	QSettings settings("TestSoft", "QSettings Test");
	settings.setValue("testName", 100);
	const QString s = "testName";
	std::cout << "Test call with char string: " 
		<< settings.value("testName", "ERROR").toString().toStdString() << std::endl
		<< "Test call with QString: " 
		<< settings.value(s, "ERROR").toString().toStdString() << std::endl
		<< "For good measure create error: "
		<< settings.value("doesNotExist", "ERROR").toString().toStdString() << std::endl;
	char t;
	std::cin >> t;
	return 0;
}

---

This is the output:

Quote:

---

C:\...>qsettings.exe
Test call with char string: 100
Test call with QString: 100
For good measure create error: ERROR

exit

C:\...>

---

I hope this helps you. If you want to compile the code above don't forget to add the following to the *.pro file as this is a console application.
CONFIG += console

-Michael

So what is the text of the problem when you try to use "QString s" instead of "const QString s"?

I think there is no compiler error, just the key is not found in the ini file.

Maybe you're missing some beginGroup("...") statement?

Ok, it works so thanks to everybody but I am not sure I solve it the best way.

QSettings is set there at the very top of the application:

Code:

---

ApplicationWindow::ApplicationWindow()
    : QMainWindow( 0 )
{   
  QCoreApplication::setOrganizationName("Adrien");
  QCoreApplication::setApplicationName("EFREI SMS");
  QSettings settings("efrei.ini", QSettings::IniFormat);

---

I had to put it public in this class AND pass it as parameter :

Code:

---

qS = iniGet( settings, "TxtCharSMSMax" ) + " " + qS2;

---

to this procedure :

Code:

---

QString ApplicationWindow::iniGet( QSettings &settings, const QString &s )
{
  QString parameter;
  QString qS3;
  QString qS4;
  parameter = settings.value( s, "ERROR" ).toString();
  if ( parameter == "ERROR" )
  {
     qS3 = "Unable to load parameter from efrei.ini";
     qS4 = s + " not found. Replaced with 'Error'"; 
     QMessageBox::critical( this, qS3, qS4 );
     parameter = "Error";
  }
  return parameter;
}

---

When QSettings settings was declared private is this same class, for some reason it was not recognized in the iniGet.

You probably didn't initialize it properly.

What do you mean initialize. I wrote :

Code:

---

class ApplicationWindow: public QMainWindow
{
    Q_OBJECT
 
private:
  QSettings    settings;

---

What else is needed.

It all looks like settings is a local variable to ApplicationWindow.

Compare those two:

Code:

---

QSettings settings("efrei.ini", QSettings::IniFormat);
QSettings settings;

---

QSettings is initialised here :

Code:

---

ApplicationWindow::ApplicationWindow()
    : QMainWindow( 0 )
{   
  QCoreApplication::setOrganizationName("Adrien");
  QCoreApplication::setApplicationName("EFREI SMS");
  QSettings settings("efrei.ini", QSettings::IniFormat);

---

If I declare in private :
QSettings settings("efrei.ini", QSettings::IniFormat);
instead of
QSettings settings;
the compiler does not accept it.

Quote:

---

Originally Posted by incapacitant

QSettings is initialised here :

Code:

---

ApplicationWindow::ApplicationWindow()
    : QMainWindow( 0 )
{   
  QCoreApplication::setOrganizationName("Adrien");
  QCoreApplication::setApplicationName("EFREI SMS");
  QSettings settings("efrei.ini", QSettings::IniFormat);

---

---

This is a local variable, not the member of the class.

Quote:

---

If I declare in private :
QSettings settings("efrei.ini", QSettings::IniFormat);
instead of
QSettings settings;
the compiler does not accept it.

---

Of course, this would be invalid.
Try this:

Code:

---

QCoreApplication::setOrganizationName("Adrien"); // you should put that in main.cpp
  QCoreApplication::setApplicationName("EFREI SMS"); // and this too
//...
ApplicationWindow::ApplicationWindow()
    : QMainWindow( 0 ), settings("efrei.ini", QSettings::IniFormat)
{

---

It works and I meet you I will ask for a brain transplant.