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How to make variable objects?

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  • mrjjM Offline
    mrjjM Offline
    mrjj
    Lifetime Qt Champion
    wrote on last edited by
    #13

    Hi
    MPlayer is a local variable and will not live after Main_Game ends.
    so you might need to make it a member of Gameplay

    M 1 Reply Last reply
    0
    • mrjjM mrjj

      Hi
      MPlayer is a local variable and will not live after Main_Game ends.
      so you might need to make it a member of Gameplay

      M Offline
      M Offline
      MasterBlade
      wrote on last edited by
      #14

      @mrjj said in How to make variable objects?:

      Hi
      MPlayer is a local variable and will not live after Main_Game ends.
      so you might need to make it a member of Gameplay

      I tried to define it as a member of Gameplay. But got an error message. What does that mean?

      class Gameplay : public QDialog
      {
      Q_OBJECT

      public:
      MPlayer p1, p2;
      //...
      }

      C:\Users\mfdsr\Documents\MasterZMDJ\gameplay.h:36: error: field 'p1' has incomplete type 'MPlayer'
      MPlayer p1, p2;

      1 Reply Last reply
      0
      • M Offline
        M Offline
        MasterBlade
        wrote on last edited by
        #15

        Nevermind, I managed to make p1 and p2 global variables.

        But still those QLabels don't appear...

        mrjjM 1 Reply Last reply
        0
        • M MasterBlade

          Nevermind, I managed to make p1 and p2 global variables.

          But still those QLabels don't appear...

          mrjjM Offline
          mrjjM Offline
          mrjj
          Lifetime Qt Champion
          wrote on last edited by
          #16

          @MasterBlade
          Dont use global variables. its not good with Qt.

          Anyway, the "incomplete type 'MPlayer'" means you forgot to include
          MPlayer.h and hence it didnt know it.

          Well, its hard to guess. What do you then do with MPlayer ? what do u insert that into ?
          Or is it a window?

          M 1 Reply Last reply
          2
          • mrjjM mrjj

            @MasterBlade
            Dont use global variables. its not good with Qt.

            Anyway, the "incomplete type 'MPlayer'" means you forgot to include
            MPlayer.h and hence it didnt know it.

            Well, its hard to guess. What do you then do with MPlayer ? what do u insert that into ?
            Or is it a window?

            M Offline
            M Offline
            MasterBlade
            wrote on last edited by
            #17

            @mrjj said in How to make variable objects?:

            @MasterBlade
            Dont use global variables. its not good with Qt.

            Anyway, the "incomplete type 'MPlayer'" means you forgot to include
            MPlayer.h and hence it didnt know it.

            Well, its hard to guess. What do you then do with MPlayer ? what do u insert that into ?
            Or is it a window?

            Actually MPlayer is just a class. I declared it in gameplay.h . It stored info for players.

            mrjjM jsulmJ 2 Replies Last reply
            0
            • M MasterBlade

              @mrjj said in How to make variable objects?:

              @MasterBlade
              Dont use global variables. its not good with Qt.

              Anyway, the "incomplete type 'MPlayer'" means you forgot to include
              MPlayer.h and hence it didnt know it.

              Well, its hard to guess. What do you then do with MPlayer ? what do u insert that into ?
              Or is it a window?

              Actually MPlayer is just a class. I declared it in gameplay.h . It stored info for players.

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

              @MasterBlade
              So what do u see in dialog ?
              None of the labels are shown ?
              I cant guess what goes wrong.

              Did you try to insert just 1 label and see ?

              1 Reply Last reply
              0
              • M MasterBlade

                @mrjj said in How to make variable objects?:

                @MasterBlade
                Dont use global variables. its not good with Qt.

                Anyway, the "incomplete type 'MPlayer'" means you forgot to include
                MPlayer.h and hence it didnt know it.

                Well, its hard to guess. What do you then do with MPlayer ? what do u insert that into ?
                Or is it a window?

                Actually MPlayer is just a class. I declared it in gameplay.h . It stored info for players.

                jsulmJ Offline
                jsulmJ Offline
                jsulm
                Lifetime Qt Champion
                wrote on last edited by
                #19

                @MasterBlade You need to call show() on your labels if you want to see them...

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

                M 1 Reply Last reply
                3
                • jsulmJ jsulm

                  @MasterBlade You need to call show() on your labels if you want to see them...

                  M Offline
                  M Offline
                  MasterBlade
                  wrote on last edited by
                  #20

                  @jsulm said in How to make variable objects?:

                  @MasterBlade You need to call show() on your labels if you want to see them...

                  I have an embarrassing problem. Those Labels are shown outside of the current window. And their positions are incorrect. I moved them to the relative position of current window. But somehow they appeared outside.

                  0_1523952747774_1.PNG

                  jsulmJ 1 Reply Last reply
                  0
                  • M MasterBlade

                    @jsulm said in How to make variable objects?:

                    @MasterBlade You need to call show() on your labels if you want to see them...

                    I have an embarrassing problem. Those Labels are shown outside of the current window. And their positions are incorrect. I moved them to the relative position of current window. But somehow they appeared outside.

                    0_1523952747774_1.PNG

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

                    @MasterBlade Why don't you simply use layouts? And I guess you did not set parent on this labels, that's why they are outside of the mainwindow.

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

                    M 1 Reply Last reply
                    2
                    • jsulmJ jsulm

                      @MasterBlade Why don't you simply use layouts? And I guess you did not set parent on this labels, that's why they are outside of the mainwindow.

                      M Offline
                      M Offline
                      MasterBlade
                      wrote on last edited by
                      #22

                      @jsulm said in How to make variable objects?:

                      @MasterBlade Why don't you simply use layouts? And I guess you did not set parent on this labels, that's why they are outside of the mainwindow.

                      Sorry I didn't go to this forum recently. I set parent label and everything works just fine.

                      I am using a customized label to store more information. That's why I created them in functions.

                      Now I am creating context menus for these labels. It looks like this. hands_s[i] are pointers for those 10 labels.

                          connect(hands_s[i], &Gameplay::customContextMenuRequested, this, &Gameplay::HandContextMenu);
                      

                      My problem is, how do I know which label I am right-clicking? Do I have to connect them with 10 different functions?

                      mrjjM 1 Reply Last reply
                      0
                      • M MasterBlade

                        @jsulm said in How to make variable objects?:

                        @MasterBlade Why don't you simply use layouts? And I guess you did not set parent on this labels, that's why they are outside of the mainwindow.

                        Sorry I didn't go to this forum recently. I set parent label and everything works just fine.

                        I am using a customized label to store more information. That's why I created them in functions.

                        Now I am creating context menus for these labels. It looks like this. hands_s[i] are pointers for those 10 labels.

                            connect(hands_s[i], &Gameplay::customContextMenuRequested, this, &Gameplay::HandContextMenu);
                        

                        My problem is, how do I know which label I am right-clicking? Do I have to connect them with 10 different functions?

                        mrjjM Offline
                        mrjjM Offline
                        mrjj
                        Lifetime Qt Champion
                        wrote on last edited by
                        #23

                        @MasterBlade
                        You can use sender() to get the QLabel;

                         QLabel* lab= qobject_cast<QLabel*>(sender());
                           if( lab ) 
                           { 
                              ...
                           }
                        
                        M 1 Reply Last reply
                        3
                        • mrjjM mrjj

                          @MasterBlade
                          You can use sender() to get the QLabel;

                           QLabel* lab= qobject_cast<QLabel*>(sender());
                             if( lab ) 
                             { 
                                ...
                             }
                          
                          M Offline
                          M Offline
                          MasterBlade
                          wrote on last edited by
                          #24

                          @mrjj said in How to make variable objects?:

                          @MasterBlade
                          You can use sender() to get the QLabel;

                           QLabel* lab= qobject_cast<QLabel*>(sender());
                             if( lab ) 
                             { 
                                ...
                             }
                          

                          That does work! Many thanks!!

                          1 Reply Last reply
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