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. Undefined reference to signal
Qt 6.11 is out! See what's new in the release blog

Undefined reference to signal

Scheduled Pinned Locked Moved Unsolved General and Desktop
2 Posts 2 Posters 7.2k Views 1 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.
  • AlvaroSA Offline
    AlvaroSA Offline
    AlvaroS
    wrote on last edited by
    #1

    Hello everyone:

    Thanks for reading this post and being able to help.

    I would like to create a signal to call a slot in another class.

    My code looks like:

    header:

    class scene_mouse_event : public QGraphicsScene
    {
    
        Q_OBJECT
    
    public:
            scene_mouse_event(QObject* parent = 0);
    
            void mousePressEvent(QGraphicsSceneMouseEvent *event);
            QPointF pt;
    
    
    signals:
            void emit_mouse_pressed();
    
    
    };
    
    #endif // SCENE_MOUSE_EVENT_H
    

    .cpp

    #include "mainwindow.h"
    #include "ui_mainwindow.h"
    #include <QtGui>
    #include <QApplication>
    #include "scene_mouse_event.h"
    
    
    scene_mouse_event::scene_mouse_event(QObject* parent): QGraphicsScene(parent){
    
    }
    
    void scene_mouse_event::mousePressEvent(QGraphicsSceneMouseEvent *event)
    {
        this->pt = event->scenePos();
        emit emit_mouse_pressed();
        QGraphicsScene::mousePressEvent(event);
    }
    
    

    but it gives me an error in "emit emit_mouse_pressed();":
    scene_mouse_event.cpp:15: error: undefined reference to `scene_mouse_event::emit_mouse_pressed()'

    and this in the constructor:
    scene_mouse_event.cpp:8: error: undefined reference to `vtable for scene_mouse_event'

    What's happening?
    Thanks!

    1 Reply Last reply
    1
    • mrjjM Offline
      mrjjM Offline
      mrjj
      Lifetime Qt Champion
      wrote on last edited by
      #2

      hi, you need to run qmake from the build menu.
      if it still stupid, then clean the build folder and rebuild all :)

      1 Reply Last reply
      5

      • Login

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