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. How to call an object created in another function.
Forum Update on Monday, May 27th 2025

How to call an object created in another function.

Scheduled Pinned Locked Moved Solved General and Desktop
c++function
17 Posts 2 Posters 5.4k Views
  • 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.
  • ronyNSR Offline
    ronyNSR Offline
    ronyNS
    wrote on last edited by
    #7

    Yes , like i want to cover my login form , but when i drag the label on the ui it resizes according to the layout.
    I used size policy , but when i run it , the main window size is fixed and cannot be reduced.
    If there is an easy way , please tell me :)

    mrjjM 1 Reply Last reply
    0
    • ronyNSR ronyNS

      Yes , like i want to cover my login form , but when i drag the label on the ui it resizes according to the layout.
      I used size policy , but when i run it , the main window size is fixed and cannot be reduced.
      If there is an easy way , please tell me :)

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

      @ronyNS
      ok, sounds like i dont understand the full setup then.
      Maybe resize event will just be easier :)

      1 Reply Last reply
      2
      • ronyNSR Offline
        ronyNSR Offline
        ronyNS
        wrote on last edited by
        #9

        Yes , Thank you ! :)

        1 Reply Last reply
        1
        • ronyNSR Offline
          ronyNSR Offline
          ronyNS
          wrote on last edited by
          #10

          Hey now i am getting 'Expected specifier before Qlabel' error . Please help

          mrjjM 1 Reply Last reply
          0
          • ronyNSR ronyNS

            Hey now i am getting 'Expected specifier before Qlabel' error . Please help

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

            @ronyNS said:

            Expected

            show line where it says it :)

            did u include <QLabel>
            in mainwindow. h?

            if its for the line
            QLabel *lbl1;

            1 Reply Last reply
            0
            • ronyNSR Offline
              ronyNSR Offline
              ronyNS
              wrote on last edited by
              #12
              void createlbl(){
              lbl1 = new QLabel("Hello");
              }
              

              Error is for this line only when i use lbl1 in other functions. Yes i have included Qlabel in .h file

              mrjjM 1 Reply Last reply
              0
              • ronyNSR ronyNS
                void createlbl(){
                lbl1 = new QLabel("Hello");
                }
                

                Error is for this line only when i use lbl1 in other functions. Yes i have included Qlabel in .h file

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

                @ronyNS
                well u are not in mainwindow method..

                void XXXX::createlbl(){

                XXXX should be mainwindow

                when there is no NAME:: in front, its NOT a member function. just a plain function.

                ronyNSR 1 Reply Last reply
                0
                • mrjjM mrjj

                  @ronyNS
                  well u are not in mainwindow method..

                  void XXXX::createlbl(){

                  XXXX should be mainwindow

                  when there is no NAME:: in front, its NOT a member function. just a plain function.

                  ronyNSR Offline
                  ronyNSR Offline
                  ronyNS
                  wrote on last edited by
                  #14

                  @mrjj
                  Still the same error

                  void MainWindow:: createlbl(){
                      lbl1 = new Qlabel();
                  }
                  

                  'expected type-specifier before QLabel

                  mrjjM 1 Reply Last reply
                  0
                  • ronyNSR ronyNS

                    @mrjj
                    Still the same error

                    void MainWindow:: createlbl(){
                        lbl1 = new Qlabel();
                    }
                    

                    'expected type-specifier before QLabel

                    mrjjM Offline
                    mrjjM Offline
                    mrjj
                    Lifetime Qt Champion
                    wrote on last edited by mrjj
                    #15

                    but it should work. ?

                    show mainwindow.h

                    here is sample that does so
                    https://www.dropbox.com/s/i0qj2e9mxbggymt/mylabel.zip?dl=0

                    1 Reply Last reply
                    2
                    • ronyNSR Offline
                      ronyNSR Offline
                      ronyNS
                      wrote on last edited by
                      #16

                      my mainwindow.h

                      #ifndef MAINWINDOW_H
                      #define MAINWINDOW_H
                      #include<QLabel>
                      #include <QMainWindow>
                      
                      namespace Ui {
                      class MainWindow;
                      }
                      
                      class MainWindow : public QMainWindow
                      {
                          Q_OBJECT
                      
                      public:
                          explicit MainWindow(QWidget *parent = 0);
                          ~MainWindow();
                          QLabel *lbl;
                      
                      protected:
                          void resizeEvent(QResizeEvent *evt) override;
                      
                      private:
                          Ui::MainWindow *ui;
                      };
                      
                      #endif // MAINWINDOW_H
                      

                      my mainwindow.cpp

                      #include "mainwindow.h"
                      #include "ui_mainwindow.h"
                      #include<QLabel>
                      
                      MainWindow::MainWindow(QWidget *parent) :
                          QMainWindow(parent),
                          ui(new Ui::MainWindow)
                      {
                          ui->setupUi(this);
                      }
                      
                      void MainWindow:: createlbl(){
                          lbl = new Qlabel();
                      }
                      
                      void MainWindow :: resizeEvent(QResizeEvent *evt)
                      {
                          MainWindow::setCentralWidget(lbl);
                          lbl->setStyleSheet("Background-color:pink");
                      
                          QMainWindow::resizeEvent(evt); //call base implementation
                      }
                      
                      MainWindow::~MainWindow()
                      {
                          delete ui;
                      }
                      
                      
                      
                      1 Reply Last reply
                      0
                      • mrjjM Offline
                        mrjjM Offline
                        mrjj
                        Lifetime Qt Champion
                        wrote on last edited by
                        #17

                        @ronyNS said:

                        lbl = new Qlabel();

                        misspelled ?
                        its QLabel ?

                        lbl = new QLabel();
                        big L ?

                        1 Reply Last reply
                        2

                        • Login

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