Force QLineEdit to be a collection of double values - c++

Question

Consider this problem.
I have a QLineEdit in my tool and I should organize a support as follows. The text of LineEdit must contain only double values, separated my comas.
F.e. 6.2 , 8, 9.0, 55
I also must validate, that user cannot input any other character but the numbers and comas. Also I should write a method which convert this text into vector.
Initially I thought about QRegExp and boost::spirit. But it can be hard using these technique.
Any ideas?

Answer 1

Use next custom Validator.
Header:
#ifndef VALIDATOR_H
#define VALIDATOR_H
#include <QValidator>
class Validator : public QValidator
{
Q_OBJECT
public:
explicit Validator(QObject *parent = 0);
signals:
public slots:
public:
QValidator::State validate(QString & input, int & pos) const;
};
#endif // VALIDATOR_H
Cpp:
#include "validator.h"
#include <QDoubleValidator>
#include <QDebug>
Validator::Validator(QObject *parent) :
QValidator(parent)
{
}
QValidator::State Validator::validate(QString &input, int &pos) const
{
qDebug() << input<< pos;
QDoubleValidator val;
val.setLocale(QLocale(QLocale::German,QLocale::Germany));
input.remove(" ");
QStringList list = input.split(",");
foreach ( QString var, list) {
int i = 0;
if(val.validate(var,i) == QValidator::Invalid)
return QValidator::Invalid;
}
return QValidator::Acceptable;
}
Usage:
ui->lineEdit->setValidator(new Validator);
Explanation about: val.setLocale(QLocale(QLocale::German,QLocale::Germany));
You said that you want use 6.2,... but . and , is different decimal point in different countries. So I wrote example accordingly to your question. German Locale always think that . is a correct point.
But I recommend you to use locale-specific decimal point and use for this Purpose ; as separator instead of coma.
There are mistakes, so try this. Edit(improved):
QValidator::State Validator::validate(QString &input, int &pos) const
{
qDebug() << input<< pos;
QRegExpValidator reg(QRegExp("[0-9]+(\\.[0-9]+)?$"));
input.remove(" ");
if(input.contains(",,") || input.startsWith(","))
return QValidator::Invalid;
QStringList list = input.split(",");
qDebug()<< list;
bool isOk = true;
foreach ( QString var, list) {
int i = 0;
if(reg.validate(var,i) == QValidator::Invalid)
return QValidator::Invalid;
if(reg.validate(var,i) == QValidator::Intermediate)
isOk = false;
}
if(isOk)
return QValidator::Acceptable;
else
return QValidator::Intermediate;
}