QMap, QHash and QByteArray

[ugluk]

I'd like to do:

QHash<QByteArray, some_type> and
QMap<QByteArray, some_type>

but can't do either, as there is no hashing function defined for QHash and no comparison function defined for QMap. I'm almost certain there exist quick fixes to this situation, just as they do with STL, please share them with me.

[mcosta]

What Qt version you're using?

This code

#ifndef WIDGET1_H
#define WIDGET1_H
 
#include <QtGui/QWidget>
 
#include <QMap>
#include <QHash>
 
namespace Ui {
    class Widget1;
}
 
class Widget1 : public QWidget
{
    Q_OBJECT
 
public:
    explicit Widget1(QWidget *parent = 0);
    ~Widget1();
 
private:
    Ui::Widget1 *ui;
 
    QMap <QByteArray, int> myMap;
    QHash <QByteArray, int> myHash;
};
 
#endif // WIDGET1_H

#ifndef WIDGET1_H
#define WIDGET1_H

#include <QtGui/QWidget>

#include <QMap>
#include <QHash>

namespace Ui {
    class Widget1;
}

class Widget1 : public QWidget
{
    Q_OBJECT

public:
    explicit Widget1(QWidget *parent = 0);
    ~Widget1();

private:
    Ui::Widget1 *ui;

    QMap <QByteArray, int> myMap;
    QHash <QByteArray, int> myHash;
};

#endif // WIDGET1_H

To copy to clipboard, switch view to plain text mode 

compile

[stampede]

This works too, with custom datatype:

#include <QtCore>
 
struct s_{
	QString str;
	int val;
};
 
int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);	
 
    s_ s; s.str = "hello"; s.val = 10;
    QMap<QByteArray,s_> map;
    QHash<QByteArray,s_> hash;
    map["string"] = s;
    hash["other key"] = s;
 
    qDebug() << map["string"].str << map["string"].val;
    qDebug() << hash["other key"].str << hash["other key"].val;
 
    return 0;
}

#include <QtCore>

struct s_{
	QString str;
	int val;
};

int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);	
   
    s_ s; s.str = "hello"; s.val = 10;
    QMap<QByteArray,s_> map;
    QHash<QByteArray,s_> hash;
    map["string"] = s;
    hash["other key"] = s;
	
    qDebug() << map["string"].str << map["string"].val;
    qDebug() << hash["other key"].str << hash["other key"].val;
	
    return 0;
}

To copy to clipboard, switch view to plain text mode 

What errors do you get ?

[ugluk]

I've upgraded to a new version and everything seems to work now, thank you for helping. I used to use 4.6.2.