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. Access and inheritance
Forum Updated to NodeBB v4.3 + New Features

Access and inheritance

Scheduled Pinned Locked Moved Solved General and Desktop
49 Posts 5 Posters 11.9k Views 4 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.
  • M mrjj
    10 Feb 2019, 18:29

    @tomy
    Hi
    Well the menu already have both shortcut and icon so not sure what else could be added.
    There is no "more advanced" menu possible by overwriting contextMenuEvent as
    you can just 100% the same just altering
    void MainWindow::createActions()
    to show what you want.

    yes, i have it as PDF. did read most of it way back.

    T Offline
    T Offline
    tomy
    wrote on 12 Feb 2019, 08:32 last edited by
    #21

    @mrjj

    Thank you very much. I was too much stuck in a QML program's problem, sorry for the delay.

    If you run the program, even by the latest version of Qt Creator and on a sophisticated and fancy operating system like Windows 10, you see the program still looks old, as though we are in 2000 using it.
    Is it because of the code? If so, what parts can be updated, please?

    M J 2 Replies Last reply 12 Feb 2019, 08:43
    0
    • T tomy
      12 Feb 2019, 08:32

      @mrjj

      Thank you very much. I was too much stuck in a QML program's problem, sorry for the delay.

      If you run the program, even by the latest version of Qt Creator and on a sophisticated and fancy operating system like Windows 10, you see the program still looks old, as though we are in 2000 using it.
      Is it because of the code? If so, what parts can be updated, please?

      M Offline
      M Offline
      mrjj
      Lifetime Qt Champion
      wrote on 12 Feb 2019, 08:43 last edited by
      #22

      @tomy
      Hi
      Nope its just how the QWidgets look.
      If you change the icons to flat style,
      it will look more "modern"

      You could use something like
      https://github.com/laserpants/qt-material-widgets
      if you want to go all in for "modern" look.

      T 1 Reply Last reply 13 Feb 2019, 09:16
      2
      • T tomy
        12 Feb 2019, 08:32

        @mrjj

        Thank you very much. I was too much stuck in a QML program's problem, sorry for the delay.

        If you run the program, even by the latest version of Qt Creator and on a sophisticated and fancy operating system like Windows 10, you see the program still looks old, as though we are in 2000 using it.
        Is it because of the code? If so, what parts can be updated, please?

        J Offline
        J Offline
        jsulm
        Lifetime Qt Champion
        wrote on 12 Feb 2019, 09:27 last edited by
        #23

        @tomy Do you use Qt4 or Qt5?

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

        T 1 Reply Last reply 12 Feb 2019, 11:45
        0
        • J jsulm
          12 Feb 2019, 09:27

          @tomy Do you use Qt4 or Qt5?

          T Offline
          T Offline
          tomy
          wrote on 12 Feb 2019, 11:45 last edited by
          #24

          @jsulm
          It's 5.12. The latest version I think.

          1 Reply Last reply
          0
          • M mrjj
            10 Feb 2019, 10:40

            @tomy
            hi
            well its MainWindow as a subclass of QMainWindow
            The names are so close its sometimes confusing.
            The truth is, if a base class do not do anything in its constructor, nothing bad will happen not calling it.
            Which seems why they didnt bother here for MainWindow

            K Offline
            K Offline
            kshegunov
            Moderators
            wrote on 12 Feb 2019, 13:27 last edited by kshegunov 2 Dec 2019, 13:32
            #25

            @mrjj said in Access and inheritance:

            The truth is, if a base class do not do anything in its constructor, nothing bad will happen not calling it.

            Just for completeness:
            If the base class has a default constructor, and it's not called explicitly in the derived class' constructor the compiler is going to generate code to call it implicitly. Omitting it in the initializer list means nothing here, as QMainWindow() is going to be called either way. If the base class does not have a default constructor, and there's no call to the parent's constructor then this is going to generate a compile error, as the compiler has no idea what to do.

            Read and abide by the Qt Code of Conduct

            T 1 Reply Last reply 12 Feb 2019, 14:01
            4
            • K kshegunov
              12 Feb 2019, 13:27

              @mrjj said in Access and inheritance:

              The truth is, if a base class do not do anything in its constructor, nothing bad will happen not calling it.

              Just for completeness:
              If the base class has a default constructor, and it's not called explicitly in the derived class' constructor the compiler is going to generate code to call it implicitly. Omitting it in the initializer list means nothing here, as QMainWindow() is going to be called either way. If the base class does not have a default constructor, and there's no call to the parent's constructor then this is going to generate a compile error, as the compiler has no idea what to do.

              T Offline
              T Offline
              tomy
              wrote on 12 Feb 2019, 14:01 last edited by
              #26

              @kshegunov
              Hi,

              If the base class has a default constructor, and it's not called explicitly in the derived class' constructor the compiler is going to generate code to call it implicitly. Omitting it in the initializer list means nothing here, as QMainWindow() is going to be called either way.

              Is it true for the Qt Creator compiler too? (I think so)

              If the base class does not have a default constructor, and there's no call to the parent's constructor then this is going to generate a compile error, as the compiler has no idea what to do.

              Can we conclude this way that, when the base class doesn't have a constructor, in either way, whether the subclass calls the parent's constructor (!) or it doesn't, we will get an error?

              K 1 Reply Last reply 12 Feb 2019, 16:05
              0
              • T tomy
                12 Feb 2019, 14:01

                @kshegunov
                Hi,

                If the base class has a default constructor, and it's not called explicitly in the derived class' constructor the compiler is going to generate code to call it implicitly. Omitting it in the initializer list means nothing here, as QMainWindow() is going to be called either way.

                Is it true for the Qt Creator compiler too? (I think so)

                If the base class does not have a default constructor, and there's no call to the parent's constructor then this is going to generate a compile error, as the compiler has no idea what to do.

                Can we conclude this way that, when the base class doesn't have a constructor, in either way, whether the subclass calls the parent's constructor (!) or it doesn't, we will get an error?

                K Offline
                K Offline
                kshegunov
                Moderators
                wrote on 12 Feb 2019, 16:05 last edited by
                #27

                @tomy said in Access and inheritance:

                Is it true for the Qt Creator compiler too? (I think so)

                Qt Creator is not a compiler, it uses some compiler (whatever you've configured), but yes, it's true for all compiler, as this is standard (and required) behaviour for C++.

                Can we conclude this way that, when the base class doesn't have a constructor, in either way, whether the subclass calls the parent's constructor (!) or it doesn't, we will get an error?

                No. Not defining a class constructor means the compiler generates a default one for you (unless specifically told otherwise). If you haven't defined a constructor in the base class, then the derived class is going to implicitly call the automatically generated one.

                Read and abide by the Qt Code of Conduct

                T 1 Reply Last reply 12 Feb 2019, 18:58
                3
                • K kshegunov
                  12 Feb 2019, 16:05

                  @tomy said in Access and inheritance:

                  Is it true for the Qt Creator compiler too? (I think so)

                  Qt Creator is not a compiler, it uses some compiler (whatever you've configured), but yes, it's true for all compiler, as this is standard (and required) behaviour for C++.

                  Can we conclude this way that, when the base class doesn't have a constructor, in either way, whether the subclass calls the parent's constructor (!) or it doesn't, we will get an error?

                  No. Not defining a class constructor means the compiler generates a default one for you (unless specifically told otherwise). If you haven't defined a constructor in the base class, then the derived class is going to implicitly call the automatically generated one.

                  T Offline
                  T Offline
                  tomy
                  wrote on 12 Feb 2019, 18:58 last edited by
                  #28

                  @kshegunov

                  So we will never have to call the base class's constructor from the subclass, because if there is an explicit constructor for the base class, the compiler calls (implicitly) for us (with the absence of an explicit call from us), and if there is no constructor for the base class, the compiler creates a default one and implicitly calls that in the subclass. Hence, we had better never involve ourselves with calling a base class's constructor directly (from the subclass)! :) :)

                  M K 2 Replies Last reply 12 Feb 2019, 19:02
                  0
                  • T tomy
                    12 Feb 2019, 18:58

                    @kshegunov

                    So we will never have to call the base class's constructor from the subclass, because if there is an explicit constructor for the base class, the compiler calls (implicitly) for us (with the absence of an explicit call from us), and if there is no constructor for the base class, the compiler creates a default one and implicitly calls that in the subclass. Hence, we had better never involve ourselves with calling a base class's constructor directly (from the subclass)! :) :)

                    M Offline
                    M Offline
                    mrjj
                    Lifetime Qt Champion
                    wrote on 12 Feb 2019, 19:02 last edited by mrjj 2 Dec 2019, 19:02
                    #29

                    @tomy
                    Hi
                    The automatic version is only for a default constructor.
                    As soon as base class constructor takes parameters, it must be called from subclass as compiler cannot
                    know how to obtain the parameters to give to base class.
                    However the compiler will tell you that.

                    1 Reply Last reply
                    3
                    • T tomy
                      12 Feb 2019, 18:58

                      @kshegunov

                      So we will never have to call the base class's constructor from the subclass, because if there is an explicit constructor for the base class, the compiler calls (implicitly) for us (with the absence of an explicit call from us), and if there is no constructor for the base class, the compiler creates a default one and implicitly calls that in the subclass. Hence, we had better never involve ourselves with calling a base class's constructor directly (from the subclass)! :) :)

                      K Offline
                      K Offline
                      kshegunov
                      Moderators
                      wrote on 12 Feb 2019, 19:39 last edited by
                      #30

                      What @mrjj said, plus the moment you define a constructor, the compiler stops generating for you. Thus if you define a constructor with parameters, the compiler will not generate a default constructor for you. Beautiful system, right? :)

                      Read and abide by the Qt Code of Conduct

                      T 1 Reply Last reply 17 Feb 2019, 07:51
                      3
                      • M mrjj
                        12 Feb 2019, 08:43

                        @tomy
                        Hi
                        Nope its just how the QWidgets look.
                        If you change the icons to flat style,
                        it will look more "modern"

                        You could use something like
                        https://github.com/laserpants/qt-material-widgets
                        if you want to go all in for "modern" look.

                        T Offline
                        T Offline
                        tomy
                        wrote on 13 Feb 2019, 09:16 last edited by
                        #31

                        @mrjj

                        If you change the icons to flat style, it will look more "modern"

                        Hi,
                        The example you posted look very modern and stylish, but too advanced for me now. Thank you.
                        I like to go step by step. So for the icons, I must download some "flat .png related files" from the Internet and substitute the old ones with these. Right?

                        M 1 Reply Last reply 13 Feb 2019, 09:58
                        0
                        • T tomy
                          13 Feb 2019, 09:16

                          @mrjj

                          If you change the icons to flat style, it will look more "modern"

                          Hi,
                          The example you posted look very modern and stylish, but too advanced for me now. Thank you.
                          I like to go step by step. So for the icons, I must download some "flat .png related files" from the Internet and substitute the old ones with these. Right?

                          M Offline
                          M Offline
                          mrjj
                          Lifetime Qt Champion
                          wrote on 13 Feb 2019, 09:58 last edited by
                          #32

                          @tomy
                          Hi
                          Yes, that could be the first step.
                          Maybe a bit of stylesheet to make QToolbar more flat to fit the new icons.
                          I dont have an image of spreadsheet app around so im not sure what else you can
                          do currently. will write of get any other ideas.

                          1 Reply Last reply
                          1
                          • K kshegunov
                            12 Feb 2019, 19:39

                            What @mrjj said, plus the moment you define a constructor, the compiler stops generating for you. Thus if you define a constructor with parameters, the compiler will not generate a default constructor for you. Beautiful system, right? :)

                            T Offline
                            T Offline
                            tomy
                            wrote on 17 Feb 2019, 07:51 last edited by
                            #33

                            @kshegunov

                            Beautiful system, right? :)

                            Right. :)

                            @mrjj

                            Yes, that could be the first step.
                            Maybe a bit of stylesheet to make QToolbar more flat to fit the new icons.
                            I dont have an image of spreadsheet app around so im not sure what else you can
                            do currently. will write of get any other ideas.

                            Hi, Thanks. So I need to lookup "stylesheet".

                            M 1 Reply Last reply 17 Feb 2019, 08:26
                            0
                            • T tomy
                              17 Feb 2019, 07:51

                              @kshegunov

                              Beautiful system, right? :)

                              Right. :)

                              @mrjj

                              Yes, that could be the first step.
                              Maybe a bit of stylesheet to make QToolbar more flat to fit the new icons.
                              I dont have an image of spreadsheet app around so im not sure what else you can
                              do currently. will write of get any other ideas.

                              Hi, Thanks. So I need to lookup "stylesheet".

                              M Offline
                              M Offline
                              mrjj
                              Lifetime Qt Champion
                              wrote on 17 Feb 2019, 08:26 last edited by
                              #34

                              @tomy

                              Hi
                              https://doc.qt.io/qt-5/stylesheet.html

                              T 2 Replies Last reply 17 Feb 2019, 09:30
                              1
                              • M mrjj
                                17 Feb 2019, 08:26

                                @tomy

                                Hi
                                https://doc.qt.io/qt-5/stylesheet.html

                                T Offline
                                T Offline
                                tomy
                                wrote on 17 Feb 2019, 09:30 last edited by
                                #35

                                @mrjj
                                Thanks to you. :)

                                1 Reply Last reply
                                0
                                • M mrjj
                                  17 Feb 2019, 08:26

                                  @tomy

                                  Hi
                                  https://doc.qt.io/qt-5/stylesheet.html

                                  T Offline
                                  T Offline
                                  tomy
                                  wrote on 18 Feb 2019, 11:07 last edited by
                                  #36

                                  @mrjj Hi,

                                  I created a new project called MySpreadsheet and added a few more options to the context menu and renewed the icons to flat ones.
                                  Now when I run the project, it runs normally, but when we close it, the follwoing message is written in the Application Output window:

                                  Starting D:\Projects\Qt\MySpreadsheet\MySpreadsheet\build-MySpreadsheet-Desktop_Qt_5_12_0_MinGW_64_bit-Debug\debug\MySpreadsheet.exe...
                                  FTH: (243752): *** Fault tolerant heap shim applied to current process. This is usually due to previous crashes. ***
                                  The program has unexpectedly finished.
                                  The process was ended forcefully.
                                  D:/Projects/Qt/MySpreadsheet/MySpreadsheet/build-MySpreadsheet-Desktop_Qt_5_12_0_MinGW_64_bit-Debug/debug/MySpreadsheet.exe crashed.

                                  What is the problem please?
                                  Is it not related to the .pro file, please?

                                  J 1 Reply Last reply 18 Feb 2019, 14:11
                                  0
                                  • T tomy
                                    18 Feb 2019, 11:07

                                    @mrjj Hi,

                                    I created a new project called MySpreadsheet and added a few more options to the context menu and renewed the icons to flat ones.
                                    Now when I run the project, it runs normally, but when we close it, the follwoing message is written in the Application Output window:

                                    Starting D:\Projects\Qt\MySpreadsheet\MySpreadsheet\build-MySpreadsheet-Desktop_Qt_5_12_0_MinGW_64_bit-Debug\debug\MySpreadsheet.exe...
                                    FTH: (243752): *** Fault tolerant heap shim applied to current process. This is usually due to previous crashes. ***
                                    The program has unexpectedly finished.
                                    The process was ended forcefully.
                                    D:/Projects/Qt/MySpreadsheet/MySpreadsheet/build-MySpreadsheet-Desktop_Qt_5_12_0_MinGW_64_bit-Debug/debug/MySpreadsheet.exe crashed.

                                    What is the problem please?
                                    Is it not related to the .pro file, please?

                                    J Offline
                                    J Offline
                                    jsulm
                                    Lifetime Qt Champion
                                    wrote on 18 Feb 2019, 14:11 last edited by
                                    #37

                                    @tomy Please run through debugger and post stack trace after it crashed...

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

                                    T 1 Reply Last reply 18 Feb 2019, 14:21
                                    0
                                    • J jsulm
                                      18 Feb 2019, 14:11

                                      @tomy Please run through debugger and post stack trace after it crashed...

                                      T Offline
                                      T Offline
                                      tomy
                                      wrote on 18 Feb 2019, 14:21 last edited by
                                      #38

                                      @jsulm
                                      Do you mean by pressing F5, please?
                                      If so, I did it, but how to post stack trace?

                                      0_1550499661735_Capture_1.PNG

                                      1 Reply Last reply
                                      0
                                      • M Offline
                                        M Offline
                                        mrjj
                                        Lifetime Qt Champion
                                        wrote on 18 Feb 2019, 14:26 last edited by
                                        #39

                                        Hi
                                        It is the list to the right we are after

                                        The code
                                        for entries Level 2,3 would help a lot.

                                        T 1 Reply Last reply 18 Feb 2019, 14:36
                                        2
                                        • M mrjj
                                          18 Feb 2019, 14:26

                                          Hi
                                          It is the list to the right we are after

                                          The code
                                          for entries Level 2,3 would help a lot.

                                          T Offline
                                          T Offline
                                          tomy
                                          wrote on 18 Feb 2019, 14:36 last edited by
                                          #40

                                          @mrjj,
                                          Hi,

                                          0_1550500483783_1.PNG

                                          Do you mean I copy and paste code for level 7 and 11 here?
                                          7 is the project's code but 11 includes thousands of lines of code.

                                          M 1 Reply Last reply 18 Feb 2019, 15:31
                                          0

                                          30/49

                                          12 Feb 2019, 19:39

                                          • Login

                                          • Login or register to search.
                                          30 out of 49
                                          • First post
                                            30/49
                                            Last post
                                          0
                                          • Categories
                                          • Recent
                                          • Tags
                                          • Popular
                                          • Users
                                          • Groups
                                          • Search
                                          • Get Qt Extensions
                                          • Unsolved