Skip to content
  • Categories
  • Recent
  • Tags
  • Popular
  • Users
  • Groups
  • Search
  • Get Qt Extensions
  • Unsolved
Collapse
Brand Logo
  1. Home
  2. Qt Development
  3. General and Desktop
  4. Basic stuff here...
Forum Updated to NodeBB v4.3 + New Features

Basic stuff here...

Scheduled Pinned Locked Moved Solved General and Desktop
22 Posts 5 Posters 3.2k Views 3 Watching
  • Oldest to Newest
  • Newest to Oldest
  • Most Votes
Reply
  • Reply as topic
Log in to reply
This topic has been deleted. Only users with topic management privileges can see it.
  • U Offline
    U Offline
    Uberlinc
    wrote on last edited by
    #1

    Hi,

    So, I'm working my way through C++ GUI Programming with Qt 4 by Blanchard and Summerfield.
    I have installed the latest version of Qt Creator (Creator 4.6.2 based on Qt 5.11.1)

    I understand that the differences between Qt 4 and Qt 5 are minimal but do exist.
    The problem is, I don't know what I don't know.

    So, working through the first chapter, I'm copying code pretty-much verbatim (apart from the odd typo here and there which, for the most part, I catch) but keep running into snags.

    I'm trying to get the GoToCell Example (Chapter 2, page 28) going... and it's like it can't see my .cpp file with the constructor as it won't allow me to declare a new class based on my defined type.
    I tried putting Ui:: in front of it to no avail.

    Is this an issue with slight variations between versions?
    Could I have made a typo someone that is stopping the compiler from seeing my class definitions?

    Any help would be appreciated!

    Thanks,

    Uberlinc.

    jsulmJ 1 Reply Last reply
    0
    • U Uberlinc

      Hi,

      So, I'm working my way through C++ GUI Programming with Qt 4 by Blanchard and Summerfield.
      I have installed the latest version of Qt Creator (Creator 4.6.2 based on Qt 5.11.1)

      I understand that the differences between Qt 4 and Qt 5 are minimal but do exist.
      The problem is, I don't know what I don't know.

      So, working through the first chapter, I'm copying code pretty-much verbatim (apart from the odd typo here and there which, for the most part, I catch) but keep running into snags.

      I'm trying to get the GoToCell Example (Chapter 2, page 28) going... and it's like it can't see my .cpp file with the constructor as it won't allow me to declare a new class based on my defined type.
      I tried putting Ui:: in front of it to no avail.

      Is this an issue with slight variations between versions?
      Could I have made a typo someone that is stopping the compiler from seeing my class definitions?

      Any help would be appreciated!

      Thanks,

      Uberlinc.

      jsulmJ Offline
      jsulmJ Offline
      jsulm
      Lifetime Qt Champion
      wrote on last edited by jsulm
      #2

      @Uberlinc said in Basic stuff here...:

      and it's like it can't see my .cpp file with the constructor as it won't allow me to declare a new class based on my defined type

      I don't understand this. Can you please explain/show what you did and what error you get?
      Also which Qt version do you use ("Creator 4.6.2 based on Qt 5.11.1" - does not tell you which Qt version you use, but which Qt version was used to build QtCreator)?

      "Basic stuff here..." - isn't a good title.

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

      1 Reply Last reply
      1
      • U Offline
        U Offline
        Uberlinc
        wrote on last edited by
        #3

        Hi,

        I wrote "Basic stuff here" because I'm still at the beginning of the book.
        Since then, I've made some changed from what I've found in other sources.

        It seems that I need:

        QT = core gui

        greaterThan(QT_MAJOR_VERSION, 4): QT += widgets

        in the .pro file.

        Why is this?
        Is this always required?

        Thanks.

        Uberlinc.

        aha_1980A 1 Reply Last reply
        0
        • U Uberlinc

          Hi,

          I wrote "Basic stuff here" because I'm still at the beginning of the book.
          Since then, I've made some changed from what I've found in other sources.

          It seems that I need:

          QT = core gui

          greaterThan(QT_MAJOR_VERSION, 4): QT += widgets

          in the .pro file.

          Why is this?
          Is this always required?

          Thanks.

          Uberlinc.

          aha_1980A Offline
          aha_1980A Offline
          aha_1980
          Lifetime Qt Champion
          wrote on last edited by
          #4

          @Uberlinc

          QT = core gui
          greaterThan(QT_MAJOR_VERSION, 4): QT += widgets
          

          Why is this?

          Because in Qt4 widgets was implicit when giving gui. In Qt5, both modules are separated for smaller libraries.

          Is this always required?

          If you don't need Qt4 compatibility (just use Qt5), you can just write:QT = core gui widgets

          Qt has to stay free or it will die.

          1 Reply Last reply
          5
          • mrjjM Offline
            mrjjM Offline
            mrjj
            Lifetime Qt Champion
            wrote on last edited by
            #5

            @Uberlinc
            hi
            Also as a note
            here you find all samples from that book
            https://github.com/mutse/qt5-book-code
            convert to work in Qt5.

            So if u get other issues related to the changes in includes,
            you can use that as reference.

            1 Reply Last reply
            6
            • U Offline
              U Offline
              Uberlinc
              wrote on last edited by
              #6

              Thanks for this.

              I've actually been using this reference:
              https://github.com/GaoHongchen/CPPGUIProgrammingWithQt4
              .... which is essentially the same.

              When I can't get my code to go, I compare side-by-side with this to see if I can spot the typo.
              It seems that there are some small differences with the latest when compared to the book.

              I'll persevere.

              Many thanks.

              mrjjM 1 Reply Last reply
              2
              • U Uberlinc

                Thanks for this.

                I've actually been using this reference:
                https://github.com/GaoHongchen/CPPGUIProgrammingWithQt4
                .... which is essentially the same.

                When I can't get my code to go, I compare side-by-side with this to see if I can spot the typo.
                It seems that there are some small differences with the latest when compared to the book.

                I'll persevere.

                Many thanks.

                mrjjM Offline
                mrjjM Offline
                mrjj
                Lifetime Qt Champion
                wrote on last edited by
                #7

                @Uberlinc
                Ok, seems fine too :)
                its just that the other link is fixed
                so it just compiles in Qt5. including all the pro file

                1 Reply Last reply
                2
                • U Offline
                  U Offline
                  Uberlinc
                  wrote on last edited by
                  #8

                  Ah! An important difference!
                  I suspect that many of my woes revolve around Qt 5 compatibility so this will be of great help!

                  Thank you once again!

                  1 Reply Last reply
                  0
                  • U Offline
                    U Offline
                    Uberlinc
                    wrote on last edited by
                    #9

                    Thanks for the Qt 5 code link.
                    It was helpful, and I went about making changes to match Qt 5 code standard.
                    However, it would seem that the code is still not working.
                    I then went about copying and pasting the raw code from the website in case it was a tiny typo that I kept missing.
                    Again, it gave the same error.

                    (I apologise. I'm struggling here!)

                    It refuses to recognise the 'buttonBox' variable in spite of:

                    1. Being created in the Design Tool
                    2. Being specified in the Design Tool Property Editor (yes, I checked syntax)
                    3. It is clearly specified in the qmake created ui_gotocell.h file.
                    4. I have ensured that the ui_gotocell.h file is included in the relevant file (and I added it to the .cpp file for good measure!)
                      It keeps giving the error "buttonBox was not declared in this scope."

                    I've been staring at it for hours.

                    Any ideas?

                    Thanks.

                    1 Reply Last reply
                    0
                    • M Offline
                      M Offline
                      MrShawn
                      wrote on last edited by
                      #10

                      Can you provide a link to your specific example?

                      1 Reply Last reply
                      1
                      • U Offline
                        U Offline
                        Uberlinc
                        wrote on last edited by
                        #11

                        https://github.com/mutse/qt5-book-code/tree/master/chap02/gotocell3

                        jsulmJ 1 Reply Last reply
                        0
                        • U Uberlinc

                          https://github.com/mutse/qt5-book-code/tree/master/chap02/gotocell3

                          jsulmJ Offline
                          jsulmJ Offline
                          jsulm
                          Lifetime Qt Champion
                          wrote on last edited by
                          #12

                          @Uberlinc It should be

                          ui->buttonBox
                          

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

                          1 Reply Last reply
                          1
                          • U Offline
                            U Offline
                            Uberlinc
                            wrote on last edited by
                            #13

                            Do you mean:

                            #include <QtWidgets>

                            #include "gotocelldialog.h"
                            #include "ui_gotocelldialog.h"

                            GoToCellDialog::GoToCellDialog(QWidget *parent)
                            : QDialog(parent)
                            {
                            setupUi(this);
                            Ui->buttonBox->button(QDialogButtonBox::Ok)->setEnabled(false);

                            QRegExp regExp("[A-Za-z][1-9][0-9]{0,2}");
                            lineEdit->setValidator(new QRegExpValidator(regExp, this));
                            
                            connect(buttonBox, SIGNAL(accepted()), this, SLOT(accept()));
                            connect(buttonBox, SIGNAL(rejected()), this, SLOT(reject()));
                            

                            }

                            void GoToCellDialog::on_lineEdit_textChanged()
                            {
                            Ui->buttonBox->button(QDialogButtonBox::Ok)->setEnabled(
                            lineEdit->hasAcceptableInput());
                            }

                            This yielded "Expected Primary Expression before ->"
                            (as well as the original two errors.)

                            I tried it with a Ui::buttonBox and it gave "buttonBox is not a member of Ui"

                            Suggestions?

                            Thanks.

                            mrjjM jsulmJ 2 Replies Last reply
                            0
                            • U Uberlinc

                              Do you mean:

                              #include <QtWidgets>

                              #include "gotocelldialog.h"
                              #include "ui_gotocelldialog.h"

                              GoToCellDialog::GoToCellDialog(QWidget *parent)
                              : QDialog(parent)
                              {
                              setupUi(this);
                              Ui->buttonBox->button(QDialogButtonBox::Ok)->setEnabled(false);

                              QRegExp regExp("[A-Za-z][1-9][0-9]{0,2}");
                              lineEdit->setValidator(new QRegExpValidator(regExp, this));
                              
                              connect(buttonBox, SIGNAL(accepted()), this, SLOT(accept()));
                              connect(buttonBox, SIGNAL(rejected()), this, SLOT(reject()));
                              

                              }

                              void GoToCellDialog::on_lineEdit_textChanged()
                              {
                              Ui->buttonBox->button(QDialogButtonBox::Ok)->setEnabled(
                              lineEdit->hasAcceptableInput());
                              }

                              This yielded "Expected Primary Expression before ->"
                              (as well as the original two errors.)

                              I tried it with a Ui::buttonBox and it gave "buttonBox is not a member of Ui"

                              Suggestions?

                              Thanks.

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

                              @Uberlinc

                              Hi
                              i think something went wrong copying stuff around
                              I just download the whole zip and open that project.
                              and it just ran.

                              so could u try try with clean project ?

                              1 Reply Last reply
                              1
                              • U Uberlinc

                                Do you mean:

                                #include <QtWidgets>

                                #include "gotocelldialog.h"
                                #include "ui_gotocelldialog.h"

                                GoToCellDialog::GoToCellDialog(QWidget *parent)
                                : QDialog(parent)
                                {
                                setupUi(this);
                                Ui->buttonBox->button(QDialogButtonBox::Ok)->setEnabled(false);

                                QRegExp regExp("[A-Za-z][1-9][0-9]{0,2}");
                                lineEdit->setValidator(new QRegExpValidator(regExp, this));
                                
                                connect(buttonBox, SIGNAL(accepted()), this, SLOT(accept()));
                                connect(buttonBox, SIGNAL(rejected()), this, SLOT(reject()));
                                

                                }

                                void GoToCellDialog::on_lineEdit_textChanged()
                                {
                                Ui->buttonBox->button(QDialogButtonBox::Ok)->setEnabled(
                                lineEdit->hasAcceptableInput());
                                }

                                This yielded "Expected Primary Expression before ->"
                                (as well as the original two errors.)

                                I tried it with a Ui::buttonBox and it gave "buttonBox is not a member of Ui"

                                Suggestions?

                                Thanks.

                                jsulmJ Offline
                                jsulmJ Offline
                                jsulm
                                Lifetime Qt Champion
                                wrote on last edited by
                                #15

                                @Uberlinc said in Basic stuff here...:

                                Ui

                                ui not Ui!

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

                                mrjjM 1 Reply Last reply
                                0
                                • U Offline
                                  U Offline
                                  Uberlinc
                                  wrote on last edited by
                                  #16

                                  I can find the code listings, but not the zip file.
                                  Am I missing it here?
                                  Can you please provide a link?

                                  Thanks.

                                  mrjjM 1 Reply Last reply
                                  0
                                  • U Uberlinc

                                    I can find the code listings, but not the zip file.
                                    Am I missing it here?
                                    Can you please provide a link?

                                    Thanks.

                                    mrjjM Offline
                                    mrjjM Offline
                                    mrjj
                                    Lifetime Qt Champion
                                    wrote on last edited by
                                    #17

                                    @Uberlinc
                                    alt text

                                    1 Reply Last reply
                                    3
                                    • jsulmJ jsulm

                                      @Uberlinc said in Basic stuff here...:

                                      Ui

                                      ui not Ui!

                                      mrjjM Offline
                                      mrjjM Offline
                                      mrjj
                                      Lifetime Qt Champion
                                      wrote on last edited by
                                      #18

                                      @jsulm
                                      It uses the old ? / other way with ui
                                      class GoToCellDialog : public QDialog, public Ui::GoToCellDialog
                                      :)

                                      1 Reply Last reply
                                      0
                                      • U Offline
                                        U Offline
                                        Uberlinc
                                        wrote on last edited by
                                        #19

                                        Okay, yes the downloaded version works.

                                        The only thing that I can think of is that when creating the form, I selected "Dialog" instead of "Widget."
                                        I must have missed that the first time around.

                                        Would this have caused this problem?

                                        Thanks.

                                        mrjjM 1 Reply Last reply
                                        0
                                        • U Uberlinc

                                          Okay, yes the downloaded version works.

                                          The only thing that I can think of is that when creating the form, I selected "Dialog" instead of "Widget."
                                          I must have missed that the first time around.

                                          Would this have caused this problem?

                                          Thanks.

                                          mrjjM Offline
                                          mrjjM Offline
                                          mrjj
                                          Lifetime Qt Champion
                                          wrote on last edited by mrjj
                                          #20

                                          @Uberlinc
                                          well for
                                          "buttonBox was not declared in this scope."
                                          i would guess on something with the UI and maybe left
                                          over files in your build folder.
                                          Using Dialog and not widget should not have changed the name of buttons / if it was created.

                                          1 Reply Last reply
                                          0

                                          • Login

                                          • Login or register to search.
                                          • First post
                                            Last post
                                          0
                                          • Categories
                                          • Recent
                                          • Tags
                                          • Popular
                                          • Users
                                          • Groups
                                          • Search
                                          • Get Qt Extensions
                                          • Unsolved