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Problem with QMap

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qmap
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  • mrjjM mrjj

    Ok, it does look perfect valid.

    have you tried
    qDebug() << size(); (in ctor)
    and
    qDebug() << par.size(); (right after u define par)

    C Offline
    C Offline
    cristiano.narcisi
    wrote on last edited by
    #5

    Ok. But what does it happen when the function is contains(..key..)?

    mrjjM 1 Reply Last reply
    0
    • C cristiano.narcisi

      Ok. But what does it happen when the function is contains(..key..)?

      mrjjM Offline
      mrjjM Offline
      mrjj
      Lifetime Qt Champion
      wrote on last edited by
      #6

      @cristiano.narcisi
      it looks like outside of constructor the key list is no more.
      i wanted to see if it says
      zero for par.

      C 1 Reply Last reply
      1
      • mrjjM mrjj

        @cristiano.narcisi
        it looks like outside of constructor the key list is no more.
        i wanted to see if it says
        zero for par.

        C Offline
        C Offline
        cristiano.narcisi
        wrote on last edited by
        #7

        @mrjj

        Ok but it is very strange. I give you another information: i can view all the key-value pair stored into the par variable using the watches of the editor!!!!

        mrjjM 1 Reply Last reply
        1
        • C cristiano.narcisi

          @mrjj

          Ok but it is very strange. I give you another information: i can view all the key-value pair stored into the par variable using the watches of the editor!!!!

          mrjjM Offline
          mrjjM Offline
          mrjj
          Lifetime Qt Champion
          wrote on last edited by
          #8

          @cristiano.narcisi
          OK ?!?! That also pretty strange.

          what about size inside and out?

          C 1 Reply Last reply
          0
          • mrjjM mrjj

            @cristiano.narcisi
            OK ?!?! That also pretty strange.

            what about size inside and out?

            C Offline
            C Offline
            cristiano.narcisi
            wrote on last edited by
            #9

            @mrjj

            Size outside the ctor is correct. It is 5!!!

            mrjjM 1 Reply Last reply
            1
            • C Offline
              C Offline
              cristiano.narcisi
              wrote on last edited by
              #10

              Using the iteartor i can view all the values stored in the QMap .... Probably i don't understand something of very important about how QMap acceses the data.
              //your code here

               QMap<const char *, QString>::ConstIterator ii;
               for( ii = par.constBegin(); ii != par.constEnd(); ++ii )
                 qDebug() << ii.key() << " = " << ii.value();```
              
              1 Reply Last reply
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              • C cristiano.narcisi

                @mrjj

                Size outside the ctor is correct. It is 5!!!

                mrjjM Offline
                mrjjM Offline
                mrjj
                Lifetime Qt Champion
                wrote on last edited by
                #11

                @cristiano.narcisi
                ok ?!?

                I think you should try dump the list using par to see if key corruption
                else there is no reason contains should not work.

                C 1 Reply Last reply
                0
                • mrjjM mrjj

                  @cristiano.narcisi
                  ok ?!?

                  I think you should try dump the list using par to see if key corruption
                  else there is no reason contains should not work.

                  C Offline
                  C Offline
                  cristiano.narcisi
                  wrote on last edited by
                  #12

                  @mrjj

                  Probably i have understood why i can retry the key. The problem is that i am using

                  QMap< const char *, QString> 
                  

                  This means that the key is a POINTER and not the text !!!

                  I have replaced the QMap template with

                  QMap< QString, QString>
                  

                  Now the key is an ITEM and not a POINTER and i can find all the keys and the value stored within the QMap.

                  Sorry for bothering you

                  Thanks for hepling me

                  Regards

                  Cristiano Narcisi

                  mrjjM 1 Reply Last reply
                  2
                  • mrjjM mrjj

                    @cristiano.narcisi said:

                    QMap

                    Hi
                    can you show the cpp of the constructor also?
                    How you add the items.

                    Inheriting from Qmap is a bit funky for me as with STL that was normally
                    not super idea. but i dont know with QList. :)

                    kshegunovK Offline
                    kshegunovK Offline
                    kshegunov
                    Moderators
                    wrote on last edited by
                    #13

                    @mrjj

                    Inheriting from Qmap is a bit funky

                    It's specially noted in the docs that deriving from a container specialization is not recommended. That's probably what seems funky ;)

                    Read and abide by the Qt Code of Conduct

                    1 Reply Last reply
                    1
                    • C cristiano.narcisi

                      @mrjj

                      Probably i have understood why i can retry the key. The problem is that i am using

                      QMap< const char *, QString> 
                      

                      This means that the key is a POINTER and not the text !!!

                      I have replaced the QMap template with

                      QMap< QString, QString>
                      

                      Now the key is an ITEM and not a POINTER and i can find all the keys and the value stored within the QMap.

                      Sorry for bothering you

                      Thanks for hepling me

                      Regards

                      Cristiano Narcisi

                      mrjjM Offline
                      mrjjM Offline
                      mrjj
                      Lifetime Qt Champion
                      wrote on last edited by
                      #14

                      @cristiano.narcisi
                      ok so
                      #define MAC_KEY "mac"
                      used as key did funky stuff?

                      good found :)

                      kshegunovK 1 Reply Last reply
                      0
                      • mrjjM mrjj

                        @cristiano.narcisi
                        ok so
                        #define MAC_KEY "mac"
                        used as key did funky stuff?

                        good found :)

                        kshegunovK Offline
                        kshegunovK Offline
                        kshegunov
                        Moderators
                        wrote on last edited by
                        #15

                        @mrjj said:

                        used as key did funky stuff?

                        The only funky stuff with that macro is that char * doesn't have a meaningful operator <, which is required for it to be a key in the map. The comparison is done as you'd compare integers.

                        Read and abide by the Qt Code of Conduct

                        1 Reply Last reply
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