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QScreen Connect Problem



  • I have configure Linux Framebuffer has /dev/fb0, Using Examples/qws/framebuffer project is working fine, but
    When I am trying to connect using QScreen object it gives th following error
    @
    QPluginLoader *objPlug = new QPluginLoader("libcheckPlugin1.so",this);
    QScreenDriverPlugin obj = qobject_cast<QScreenDriverPlugin>(objPlug->instance());
    QScreen *objScr = obj->create("dbscreen",QScreen::LinuxFBClass);
    objScr->connect("LinuxFb:/dev/fb0" );
    objScr->initDevice();@

    It gives segementation fault.

    Kindly give me solution to connect the Framebuffer using QScreen plugin.


  • Lifetime Qt Champion

    Hi,

    You should add some sanity check to your code. You don't verify that the plugin is correctly loaded, nor that any object is valid.



  • @ QPluginLoader *objPlug = new QPluginLoader("libcheckPlugin1.so",this);
    QScreenDriverPlugin obj = qobject_cast<QScreenDriverPlugin>(objPlug->instance());

    • if(obj != NULL)
      qDebug()<<"Object Reference:"<<obj->keys();
    • QScreen *objScr = obj->create("dbscreen",QScreen::LinuxFBClass);
      objScr->connect("LinuxFb:/dev/fb0" );
      objScr->initDevice();;@

    I have added the object check to my code and it is valid Screen plugin. but when I am trying to initdevice it is throwing segmentation fault. please let me know any certain configuration are required to init framebuffer device.


  • Lifetime Qt Champion

    Do you have a stack trace of the crash ?



  • I dont find any stack trace but give me clue to debug any stack trace for this object.


  • Lifetime Qt Champion

    Then you should run your application using a debugger so you would be able to see where exactly it crashes


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