Conflict type QString and std::string in a parameter

Question

I think my problem is simple to solve, but due to my lack of knowledge, I can't find the answer.

I have this structure :

struct variableOutil {
    std::string Nom;   
    float Valeur;   
    std::string Module;    
    std::string Unite;    
    std::string Format;    
    std::string Accesibilite;    
    std::string Description ;
};

And the problem come from here :

struct variableOutil ToleranceTensionAvion;
ToleranceTensionAvion.Nom = "ToleranceTensionAvion";
QTableWidgetItem* newItem = new QTableWidgetItem();
newItem->setText(ToleranceTensionAvion.Nom);
this->ui->variableTableWidget->setItem(1,0,newItem);

I've got this error :

No matching function for call to 'QTableWidgetItem::setText(std::string&)

The problem is that setText need a const QString &text and tell me that I put in parameter a std::string& , I don't understand why does the type don't match, and what's the difference, after all, this is a simple String.

Thank you.

Because in the end it's just this : " " And how to put Qstring in my structure so ? — Evans Belloeil, Jun 03 '14 at 10:20
possible duplicate of http://stackoverflow.com/questions/1814189/how-to-change-string-into-qstring — lpapp, Jun 04 '14 at 01:28

score 3 · Accepted Answer · edited Jun 03 '14 at 10:26

3

You should convert std::string to QString by :

newItem->setText(QString::fromStdString(ToleranceTensionAvion.Nom));

Or

newItem->setText(QString::fromUtf8(ToleranceTensionAvion.Nom.c_str());

edited Jun 03 '14 at 10:26

Rakib

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answered Jun 03 '14 at 10:25

Nejat

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score 2 · Answer 2 · edited Jun 03 '14 at 10:32

2

Try:

newItem->setText(QString::fromUtf8(ToleranceTensionAvion.Nom.c_str());

QString allows only Unicode. std::string just stores the bytes and does not work with encodings. The best way to store your texts would probably be UTF-8 encoding.

edited Jun 03 '14 at 10:32

Rakib

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answered Jun 03 '14 at 10:29

Matthias

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Rakib · Answer 3 · 2014-06-03T10:33:11.817

1

They are completely different classes, and std::stringcan not be used in place of QString. You can build QString fromstd::string and pass it.

QString s =QString::fromStdString(ToleranceTensionAvion.Nom);
newItem->setText(s);

edited Jun 03 '14 at 10:33

answered Jun 03 '14 at 10:21

Rakib

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score 1 · Answer 4 · answered Jun 03 '14 at 13:46

1

just use c._str() on your std::string and it will work for anything that expects a QString

answered Jun 03 '14 at 13:46

AngryDuck

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Conflict type QString and std::string in a parameter

4 Answers4