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How to prevent space bar event from the QLineEdit

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  • jsulmJ jsulm

    @maniron See documentation(https://doc.qt.io/qt-5/qlineedit.html#inputMask-prop):
    "A space character, the default character for a blank, is needed for cases where a character is permitted but not required."
    You can use 9 instead of 0, but then you will need to fill with 0 like: 127.000.000.001

    Another possibility is https://doc.qt.io/qt-5/qlineedit.html#setValidator and https://doc.qt.io/qt-5/qregularexpressionvalidator.html

    ManiRonM Offline
    ManiRonM Offline
    ManiRon
    wrote on last edited by
    #3

    @jsulm Any sample example will be availabe ?

    jsulmJ 1 Reply Last reply
    0
    • ManiRonM ManiRon

      @jsulm Any sample example will be availabe ?

      jsulmJ Offline
      jsulmJ Offline
      jsulm
      Lifetime Qt Champion
      wrote on last edited by
      #4

      @maniron Example for what exactly?

      https://forum.qt.io/topic/113070/qt-code-of-conduct

      ManiRonM 1 Reply Last reply
      0
      • jsulmJ jsulm

        @maniron Example for what exactly?

        ManiRonM Offline
        ManiRonM Offline
        ManiRon
        wrote on last edited by
        #5

        @jsulm I dont want space when spacce key is pressed , it should be rejected when space key is pressed in lineedit

        jsulmJ 1 Reply Last reply
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        • ManiRonM ManiRon

          @jsulm I dont want space when spacce key is pressed , it should be rejected when space key is pressed in lineedit

          jsulmJ Offline
          jsulmJ Offline
          jsulm
          Lifetime Qt Champion
          wrote on last edited by
          #6

          @maniron I already suggested to use a validator (setValidator) based on regular expression.

          https://forum.qt.io/topic/113070/qt-code-of-conduct

          ManiRonM 2 Replies Last reply
          1
          • jsulmJ jsulm

            @maniron I already suggested to use a validator (setValidator) based on regular expression.

            ManiRonM Offline
            ManiRonM Offline
            ManiRon
            wrote on last edited by
            #7

            @jsulm ok i will see through it

            1 Reply Last reply
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            • jsulmJ jsulm

              @maniron I already suggested to use a validator (setValidator) based on regular expression.

              ManiRonM Offline
              ManiRonM Offline
              ManiRon
              wrote on last edited by ManiRon
              #8

              @jsulm I tried to understand QRegExpValidator But donno whats wrong in this code

                 QRegExp rx("[0-9]\\d{1,255}");
              // the validator treats the regexp as "^[1-9]\\d{0,3}$"
              QRegExpValidator *ipValidator = new QRegExpValidator(rx, this);
              //QRegExpValidator v(rx, 0);
              
              
              ui->lineEdit->setValidator(ipValidator);
              

              Can any one help me out in understanding the QRegExp . If I set this validator , Its not accepting any numbers or letters in the lineedit

              jsulmJ 1 Reply Last reply
              1
              • ManiRonM ManiRon

                @jsulm I tried to understand QRegExpValidator But donno whats wrong in this code

                   QRegExp rx("[0-9]\\d{1,255}");
                // the validator treats the regexp as "^[1-9]\\d{0,3}$"
                QRegExpValidator *ipValidator = new QRegExpValidator(rx, this);
                //QRegExpValidator v(rx, 0);
                
                
                ui->lineEdit->setValidator(ipValidator);
                

                Can any one help me out in understanding the QRegExp . If I set this validator , Its not accepting any numbers or letters in the lineedit

                jsulmJ Offline
                jsulmJ Offline
                jsulm
                Lifetime Qt Champion
                wrote on last edited by
                #9

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

                [0-9]\d{1,255}

                This is wrong: {1,255} means between one and 255 occurrences of the character before.
                This is your reg exp:

                ([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])
                

                Take a look at
                http://gamon.webfactional.com/regexnumericrangegenerator/
                https://regex101.com

                https://forum.qt.io/topic/113070/qt-code-of-conduct

                ManiRonM 1 Reply Last reply
                3
                • jsulmJ jsulm

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

                  [0-9]\d{1,255}

                  This is wrong: {1,255} means between one and 255 occurrences of the character before.
                  This is your reg exp:

                  ([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])
                  

                  Take a look at
                  http://gamon.webfactional.com/regexnumericrangegenerator/
                  https://regex101.com

                  ManiRonM Offline
                  ManiRonM Offline
                  ManiRon
                  wrote on last edited by ManiRon
                  #10

                  @jsulm

                    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

                  jsulmJ 1 Reply Last reply
                  0
                  • ManiRonM ManiRon

                    @jsulm

                      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

                    jsulmJ Offline
                    jsulmJ Offline
                    jsulm
                    Lifetime Qt Champion
                    wrote on last edited by
                    #11

                    @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]))"
                    

                    https://forum.qt.io/topic/113070/qt-code-of-conduct

                    ManiRonM 1 Reply Last reply
                    1
                    • jsulmJ 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]))"
                      
                      ManiRonM Offline
                      ManiRonM Offline
                      ManiRon
                      wrote on last edited by
                      #12

                      @jsulm I am using QT 5.5.0

                      JonBJ 1 Reply Last reply
                      0
                      • ManiRonM ManiRon

                        @jsulm I am using QT 5.5.0

                        JonBJ Offline
                        JonBJ Offline
                        JonB
                        wrote on last edited by
                        #13

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

                        ManiRonM 1 Reply Last reply
                        3
                        • mrjjM Offline
                          mrjjM Offline
                          mrjj
                          Lifetime Qt Champion
                          wrote on last edited by
                          #14

                          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.

                          1 Reply Last reply
                          0
                          • JonBJ JonB

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

                            ManiRonM Offline
                            ManiRonM Offline
                            ManiRon
                            wrote on last edited by
                            #15

                            @jonb it doesnt show any co mpiler version

                            JonBJ jsulmJ 2 Replies Last reply
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                            • ManiRonM ManiRon

                              @jonb it doesnt show any co mpiler version

                              JonBJ Offline
                              JonBJ Offline
                              JonB
                              wrote on last edited by JonB
                              #16

                              @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.

                              1 Reply Last reply
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                              • ManiRonM ManiRon

                                @jonb it doesnt show any co mpiler version

                                jsulmJ Offline
                                jsulmJ Offline
                                jsulm
                                Lifetime Qt Champion
                                wrote on last edited by
                                #17

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

                                https://forum.qt.io/topic/113070/qt-code-of-conduct

                                ManiRonM 1 Reply Last reply
                                2
                                • jsulmJ jsulm

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

                                  ManiRonM Offline
                                  ManiRonM Offline
                                  ManiRon
                                  wrote on last edited by
                                  #18

                                  @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);
                                  
                                  jsulmJ 1 Reply Last reply
                                  0
                                  • ManiRonM 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);
                                    
                                    jsulmJ Offline
                                    jsulmJ Offline
                                    jsulm
                                    Lifetime Qt Champion
                                    wrote on last edited by
                                    #19

                                    @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?

                                    https://forum.qt.io/topic/113070/qt-code-of-conduct

                                    ManiRonM 1 Reply Last reply
                                    0
                                    • jsulmJ 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?

                                      ManiRonM Offline
                                      ManiRonM Offline
                                      ManiRon
                                      wrote on last edited by
                                      #20

                                      @jsulm yes

                                      jsulmJ 1 Reply Last reply
                                      0
                                      • ManiRonM ManiRon

                                        @jsulm yes

                                        jsulmJ Offline
                                        jsulmJ Offline
                                        jsulm
                                        Lifetime Qt Champion
                                        wrote on last edited by
                                        #21

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

                                        https://forum.qt.io/topic/113070/qt-code-of-conduct

                                        ManiRonM 1 Reply Last reply
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                                        • jsulmJ jsulm

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

                                          ManiRonM Offline
                                          ManiRonM Offline
                                          ManiRon
                                          wrote on last edited by
                                          #22

                                          @jsulm in my constructor

                                          jsulmJ 1 Reply Last reply
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