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Advice about the application I will be making? (I'm a beginner)

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  • mrjjM mrjj

    @dvlpr.bernard said in Advice about the application I will be making? (I'm a beginner):

    Do I need objects and classes (not that familiar with that) or mostly I would use functions?

    You will be mostly used classes since all Widgets are classes.
    the Print_Question should be a member function to the MainWindow so
    it can access the widgets. You can use QLabel for the topic (call setText on it)
    and QPlainTextEdit for the user / answer input.
    The design looks fine. You can realize it with a stacked widget.

    for both the Topic and Level selection, you have 2 options.
    1: as soon as the user click button, its selected and page is changed.
    2: You set Checkable on the buttons, so they are like a checkbox ( can be selected) and
    first when user press next, the page is changed.

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    dvlpr.bernard
    wrote on last edited by
    #24

    @mrjj
    Good day!

    Is it possible to store a long string in SQLite database or maybe an image? I need it for the questions or do I?

    0_1556191665411_732ce764-c6ca-43bb-9503-7d7f32a626a5-image.png

    mrjjM 1 Reply Last reply
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    • D dvlpr.bernard

      @mrjj
      Good day!

      Is it possible to store a long string in SQLite database or maybe an image? I need it for the questions or do I?

      0_1556191665411_732ce764-c6ca-43bb-9503-7d7f32a626a5-image.png

      mrjjM Offline
      mrjjM Offline
      mrjj
      Lifetime Qt Champion
      wrote on last edited by
      #25

      Hi
      Storing text in Sqllite should just work. use the TEXT type for the column.

      Im not sure what you would need any images for ?

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      • mrjjM mrjj

        Hi
        Storing text in Sqllite should just work. use the TEXT type for the column.

        Im not sure what you would need any images for ?

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        dvlpr.bernard
        wrote on last edited by
        #26

        Okay, did you mean this string? I already tried it but it didn't work I think it is one liner meaning I can't put two or more line data.

        0_1556192247323_cb9def4a-6675-4b99-9615-d7151c9d178c-image.png

        I want store an image to make it look more a real code rather than just a plain text, but if it is not possible thats fine.
        0_1556192503849_c8f12403-d6c9-48af-bb84-37ba1b9cdfa5-image.png

        mrjjM 1 Reply Last reply
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        • D dvlpr.bernard

          Okay, did you mean this string? I already tried it but it didn't work I think it is one liner meaning I can't put two or more line data.

          0_1556192247323_cb9def4a-6675-4b99-9615-d7151c9d178c-image.png

          I want store an image to make it look more a real code rather than just a plain text, but if it is not possible thats fine.
          0_1556192503849_c8f12403-d6c9-48af-bb84-37ba1b9cdfa5-image.png

          mrjjM Offline
          mrjjM Offline
          mrjj
          Lifetime Qt Champion
          wrote on last edited by
          #27

          @dvlpr.bernard
          where you have string, if u open drop down, there is not TEXT type ?

          ahh. that way.
          well we can fix that later with a syntax highlighter
          https://doc.qt.io/qt-5/qtwidgets-richtext-syntaxhighlighter-example.html
          so when we set text texts its formatted with colors. no need to store image of it.

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          • mrjjM mrjj

            @dvlpr.bernard
            where you have string, if u open drop down, there is not TEXT type ?

            ahh. that way.
            well we can fix that later with a syntax highlighter
            https://doc.qt.io/qt-5/qtwidgets-richtext-syntaxhighlighter-example.html
            so when we set text texts its formatted with colors. no need to store image of it.

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            dvlpr.bernard
            wrote on last edited by
            #28

            @mrjj
            Uhhmm I see, I need to use Text rather than string.
            Thank you, thank you!

            mrjjM 1 Reply Last reply
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            • D dvlpr.bernard

              @mrjj
              Uhhmm I see, I need to use Text rather than string.
              Thank you, thank you!

              mrjjM Offline
              mrjjM Offline
              mrjj
              Lifetime Qt Champion
              wrote on last edited by
              #29

              @dvlpr.bernard
              string is a way to optimize the db so one can set a fixed size so if all text is within that, its more efficient, however, for your case with 75 questions. just use TEXT type.

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              • mrjjM mrjj

                @dvlpr.bernard
                string is a way to optimize the db so one can set a fixed size so if all text is within that, its more efficient, however, for your case with 75 questions. just use TEXT type.

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                dvlpr.bernard
                wrote on last edited by
                #30

                @mrjj
                Sir. Just wondering how can I access the string value from other functions? I want to use it in other functions.

                0_1556204335320_ff86f8e5-34df-453a-887c-a9a1f3df8d9f-image.png

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                • mrjjM Offline
                  mrjjM Offline
                  mrjj
                  Lifetime Qt Champion
                  wrote on last edited by
                  #31

                  Hi
                  what string do you mean ?
                  The Topic column string from the data base ?

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                  • mrjjM mrjj

                    Hi
                    what string do you mean ?
                    The Topic column string from the data base ?

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                    dvlpr.bernard
                    wrote on last edited by
                    #32

                    @mrjj Hello, no. I mean the QString ch_topic whenever the user chooses a topic. How I'm going to get the ch_topic in order to use it in other functions?

                    mrjjM 1 Reply Last reply
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                    • D dvlpr.bernard

                      @mrjj Hello, no. I mean the QString ch_topic whenever the user chooses a topic. How I'm going to get the ch_topic in order to use it in other functions?

                      mrjjM Offline
                      mrjjM Offline
                      mrjj
                      Lifetime Qt Champion
                      wrote on last edited by mrjj
                      #33

                      @dvlpr.bernard
                      Hi
                      Just store in main window class.
                      All the data you want to be shared between functions should be part of MainWindow. (in .h)
                      At least stuff like selected Topic etc.

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                      • mrjjM mrjj

                        @dvlpr.bernard
                        Hi
                        Just store in main window class.
                        All the data you want to be shared between functions should be part of MainWindow. (in .h)
                        At least stuff like selected Topic etc.

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                        dvlpr.bernard
                        wrote on last edited by
                        #34

                        @mrjj
                        Hello, Hmm didn't know why this is happening. What I did wrong?

                        0_1556212301978_004fed1f-b35c-473b-ac23-46e096ec3041-image.png
                        0_1556212325470_a4634d6a-f4a2-4b72-a254-2cd4b79ab393-image.png

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                        • mrjjM Offline
                          mrjjM Offline
                          mrjj
                          Lifetime Qt Champion
                          wrote on last edited by mrjj
                          #35

                          Hi
                          You say get_ch_topic is of type MainWindow ???
                          Should it not QString ?
                          Or do you mean it should be a function to return
                          the ch_topic ?
                          In any case, type of MainWindow just seems wrong.

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                          • mrjjM mrjj

                            Hi
                            You say get_ch_topic is of type MainWindow ???
                            Should it not QString ?
                            Or do you mean it should be a function to return
                            the ch_topic ?
                            In any case, type of MainWindow just seems wrong.

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                            dvlpr.bernard
                            wrote on last edited by
                            #36

                            @mrjj
                            I don't know. But I want to define a global object so that other functions can use it. But I just don't know where to declare it

                            mrjjM 1 Reply Last reply
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                            • D dvlpr.bernard

                              @mrjj
                              I don't know. But I want to define a global object so that other functions can use it. But I just don't know where to declare it

                              mrjjM Offline
                              mrjjM Offline
                              mrjj
                              Lifetime Qt Champion
                              wrote on last edited by
                              #37

                              @dvlpr.bernard
                              Hi
                              Just like the
                              QString ch_topic;
                              Then all member functions have access to it as they are part of the class.

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                              • mrjjM mrjj

                                @dvlpr.bernard
                                Hi
                                Just like the
                                QString ch_topic;
                                Then all member functions have access to it as they are part of the class.

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                                dvlpr.bernard
                                wrote on last edited by
                                #38

                                @mrjj
                                whenever I use qDebug() <<get_ch_Topic.getTopic() in the same function where ch_topic was define it returns "IF". But when I use qDebug() <<get_ch_Topic.getTopic() in other functions it return "". I don't know why but maybe because the object name was different?

                                0_1556213404603_c1fd677f-9d65-4757-823b-cd0ca12c8cd1-image.png

                                0_1556213335075_393dae0b-1e06-4d26-b205-1442f8e031ab-image.png
                                0_1556213772599_8a754c36-c9f0-4944-9321-6a467c0b3431-image.png
                                0_1556213365670_97704c96-1c78-4e8d-a8f3-d6ed2356bc05-image.png

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                                • mrjjM Offline
                                  mrjjM Offline
                                  mrjj
                                  Lifetime Qt Champion
                                  wrote on last edited by mrjj
                                  #39

                                  Hi
                                  Do NOT make new instances of the main window class like you do
                                  alt text

                                  that is just plain wrong.

                                  You are already in an instance. So no need to ever make new ones.
                                  you can simply use the ch_topic variable.
                                  Its already declared in the MainWindow you are using already.

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                                  • mrjjM mrjj

                                    Hi
                                    Do NOT make new instances of the main window class like you do
                                    alt text

                                    that is just plain wrong.

                                    You are already in an instance. So no need to ever make new ones.
                                    you can simply use the ch_topic variable.
                                    Its already declared in the MainWindow you are using already.

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                                    dvlpr.bernard
                                    wrote on last edited by
                                    #40

                                    @mrjj
                                    Sir, that's what I did before but whenever I do that it says 0_1556214114582_f2ded59c-c3a3-4d57-aae1-428aaa89e276-image.png

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                                    • mrjjM Offline
                                      mrjjM Offline
                                      mrjj
                                      Lifetime Qt Champion
                                      wrote on last edited by mrjj
                                      #41

                                      well
                                      just use the variable directly. no need to use function.
                                      im not sure what get_ch_tipic is as you dont have () so its not function call.

                                      However, if you do

                                      QString MyX; ( in .h as you shown)

                                      then anywhere you can just use it like

                                      MyX = "";
                                      or read it.

                                      alt text
                                      is just bad syntax.
                                      as you say get_ch_Topic is a object with the function getTopic and its not true.

                                      if you gave MainWindow a function called getTopic
                                      then just call it
                                      qDebug() << getTopic();

                                      Its important to understand that all you add to MainWindow class ( in .h)
                                      can be access from any functio that also a memebr .
                                      that is
                                      MainWindow::SomeFunction() {
                                      any variable from .h you can use here. no special syntax. just use it.
                                      }

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                                        dvlpr.bernard
                                        wrote on last edited by
                                        #42

                                        Thank you sir. I just don't know but still it doesn't work it just return "" not "WHILE". :(

                                        mrjjM 1 Reply Last reply
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                                        • D dvlpr.bernard

                                          Thank you sir. I just don't know but still it doesn't work it just return "" not "WHILE". :(

                                          mrjjM Offline
                                          mrjjM Offline
                                          mrjj
                                          Lifetime Qt Champion
                                          wrote on last edited by
                                          #43

                                          @dvlpr.bernard
                                          hi
                                          check code where you set it.
                                          Maybe you create other instance you set it on ?

                                          D 1 Reply Last reply
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