How to prevent space bar event from the QLineEdit

ManiRon

  QRegExp rx("([0-9]|[1-8][0-9]|9[0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])\.([0-9]|[1-8][0-9]|9[0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])\.([0-9]|[1-8][0-9]|9[0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])\.([0-9]|[1-8][0-9]|9[0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])");

Is this right ? cause same problem arises the line edit is not accepting any numbers

jsulm

@maniron You know that you have to escape special characters in C++ string literals?
If you have C++11 compiler you can simply do

R"(([0-9]|[1-8][0-9]|9[0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])\.([0-9]|[1-8][0-9]|9[0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])\.([0-9]|[1-8][0-9]|9[0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])\.([0-9]|[1-8][0-9]|9[0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5]))"

ManiRon

@jsulm I am using QT 5.5.0

JonB

@maniron
You have to tell @jsulm which compiler version you are using, not which Qt version.

mrjj

Hi
try to add
CONFIG += c++11
to your .pro file and run qmake
it should work.
Then you can use the handy R" syntax and avoid
having to escape the exp string.

ManiRon

@jonb it doesnt show any co mpiler version

JonB

@maniron
What doesn't show any compiler version? If you are developing with Qt you should know which compiler you chose and what version it is at, that was your choice, not Qt's.

jsulm

@maniron The compiler is configured in the Kit.
But actually you could simply copy what I posted and see whether it works...

ManiRon

@jsulm
I tried adding this but still the line edit is not getting any input
ui->lineEdit->setInputMask("000.000.000.000");

  QRegExp rx(R"(([0-9]|[1-8][0-9]|9[0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])\.([0-9]|[1-8][0-9]|9[0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])\.([0-9]|[1-8][0-9]|9[0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])\.([0-9]|[1-8][0-9]|9[0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5]))");
// the validator treats the regexp as "^[1-9]\\d{0,3}$"
QRegExpValidator *ipValidator = new QRegExpValidator(rx, this);
ui->lineEdit->setValidator(ipValidator);

jsulm

@maniron said in How to prevent space bar event from the QLineEdit:

line edit is not getting any input

Do you mean you can't input anything?

ManiRon

@jsulm yes

jsulm

@maniron Works for me. Where did you put that code?

ManiRon

@jsulm in my constructor

jsulm

@maniron Please show your constructor

ManiRon

@jsulm

MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);
ui->lineEdit->setInputMask("000.000.000.000");
QRegExp rx(R"(([0-9]|[1-8][0-9]|9[0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5]).([0-9]|[1-8][0-
9]|9[0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5]).([0-9]|[1-8][0-9]|9[0-9]|1[0-9]{2}|2[0-4][0-
9]|25[0-5]).([0-9]|[1-8][0-9]|9[0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5]))");
// the validator treats the regexp as "^[1-9]\d{0,3}$"
QRegExpValidator *ipValidator = new QRegExpValidator(rx, this);

ui->lineEdit->setValidator(ipValidator);

}

jsulm

@maniron said in How to prevent space bar event from the QLineEdit:

ui->lineEdit->setInputMask("000.000.000.000");

Why is this line there?

ManiRon

@jsulm to form the IP format

jsulm

@maniron said in How to prevent space bar event from the QLineEdit:

to form the IP format

For that you now have the validator!

ManiRon

@jsulm Yes it worked but if the user is giving an input which is not in the form of an Ip
(For Example : I am entering an input as 255 and pressing a button also it accepts the input )
Is there a way which checks whether the entered Ip address is in the form of an IP Address

jsulm

@maniron You can do this when the user presses the button. To do so you can even use same regular expression.