[Solved] QDoubleValidator, allow to enter ".00..." and to disable ",00"

[newe12]

Hi!

I am using QDoubleValidator which works fine, except two things:

1. If someone would like to enter ".001", it is required to type "0."

Isn't there a solution, where the user could just type ".001" and miss out the "0" before the point?

I have:

QValidator *validator = new QDoubleValidator(.0, 1.0, 10, lineedit);
 lineedit->setValidator(validator);

2. It is also possible to enter ",00...". This option with a "comma" I would like to disable.

Therefore, I would like to enable to enter a number with decimal places, that the user can

1. directly start with "." (or optional with "0.") and
2. to disable the possibility to enter a "comma" (e.g. "," and "0,").

I'd appreciate any useful ideas!

[koahnig]

@newe12
Probably QRegExpValidator provides the extended flexibility you need.
Another possibility is the inputMask

[roseicollis]

@newe12 As koahnig says you need a QRegExpValidator. You have to be carefull with dot (.) so u have to scape it. I let u an example to see how it works:

 QRegExp rx("[\\.]\\d{0,30}"); // See that I don't put "." but "\\."
    QValidator *validator7 = new QRegExpValidator(rx, this);
    your_LineEdit->setValidator(validator7);

In this case this will accept a dot and then from 0 to 30 numbers p.e: .0 / .123 / .12345678912346579 /

[newe12]

Hi @koahnig and @roseicollis!

thank you very much!

It nearly works:

QRegExp rx("[\\.]\\d{0,10}");
QValidator *validator = new QRegExpValidator(rx, this);
lineedit->setValidator(validator);

But, how can I enable to type additionally "0."?

[roseicollis]

@newe12

It was just an example to let you see how it works because I had so much problems with that issue too and all help was so apreciated. I'm not an expert on this and I don't know if this is best way but maybe you need something like this:

    QRegExp rx7("[0-9\\.\\0-9]{0,7}"); // 0,7 allows you to write from 0 to 7 numbers like 0.2 or 0.23568 or 123.56

As I don't know exactly what u need u will have to play whith this on your own and find which is your best combination. Here you can read more about QRegExp: Documentation

[newe12]

@roseicollis

thank you very much!

Well, nearly!

If I use

QRegExp rx("[0\\.]\\d{0,10}");

I can enter ".xy" as intended, but also "0xy" as not intended, instead of "0.xy" as planned.

Almost...

[SGaist]

Hi,

It's rather "0?\\.\\d{0,10}"
Optional 0, mandatory point, then from 0 to 10 number

[newe12]

Perfect! That's it! Solved!

@SGaist Thanks very much!