Qt World Summit: Submit your Presentation

Singleton instance of QSplashScreen

  • how to use QSplashScreen in an application of 100 files and each file has to change the message of QSplashScreen using showMessage.
    i.e., singleton instance of splash screen.

    pls any one show me light.

  • You can make wrapper class for working with QSplashScreen and use it as singleton.

  • since i'm a newbie ,could you please explain how to may use of wrapper class.

  • Just create your own custom singleton-class which will have private QSplashScreen field and two public methods: one for setting this field (from place where you are creating splashscreen) and second for setting message.

  • Thanks for ur reply..

    I have created the singleton class SplashScreen
    i'm using this

    to set the message at different files.
    But still i have a doubt where to initialize QApplication.

  • Mmm, QApplication is commonly initialized in main() method. Maybe you mean QSplashScreen? If yes, than I think it will be ok for you to init it in main() too.

  • @class MySplash : public QSplashScreen
    explicit MySplash(QObject parent = 0);
    static MySplash

    MySplash* _inst;
    MySplash::_inst = 0;
    MySplash* MySplash::instance()
    if ( !_inst )
    _inst = new MySplash();
    return _inst;

  • @class SplashScreen : public QSplashScreen{


    static SplashScreen* getInstance();

    void destroyInstance();
    void SetSplashScreen();
    void SetMessage(const std::wstring& message);
    QString *splashMessage;
    CString progressText;

    QSplashScreen *hostSplash_;
    SplashScreen() {}


    static SplashScreen* m_pInstance;

    };@.h file

  • @SplashScreen* SplashScreen::m_pInstance = NULL;

    SplashScreen* SplashScreen::getInstance() {

    if(NULL == m_pInstance ) {

    m_pInstance = new SplashScreen();

    return m_pInstance;

    void SplashScreen::destroyInstance() {

    delete m_pInstance;
    m_pInstance = NULL;

    void SplashScreen::SetMessage(const std::wstring& message ) {

    progressText = message.c_str();
    char pC = (char)(LPCTSTR)progressText ;

    void SplashScreen::SetSplashScreen() {
    hostSplash_ = new QSplashScreen(QPixmap(":Resource Files/splash.jpg"));

  • prakash02, and?

  • This is .cpp file.

    I initialized the QApplication in main function, but my doubt does i can use the SplashScreen instance other than from main class.

    Any help is appreciable.Thanks in advance.

  • prakash02, @SplashScreen* SplashScreen::m_pInstance = NULL;@ it's C style, it's better to use C++ style:
    @SplashScreen* SplashScreen::m_pInstance = 0;@

  • And why do you use std::wstring instead QString?

  • I defined resource file of strings,now i want to use those messages to be display on QSplashScreen when the program execution calls that function which can be on different namespace or on different class.

  • Why do you use CString and std::wstring for setting/storing text? Why not QString? Also using CString and LPCTSTR type will break cross-platform compatibility.

  • Denis Kormalev. :)

  • 2moderators of this section: please move this thread to more correspondent category (Desktop I think)

  • prakash02, how do you defiine resource file of strings?

  • Yes i can use QString, but previously those are used to display on the native windows dialog.Now I want to change those to QT to improve the look and feel.

  • try to use QObject::tr("") for strings instead string table in resource file.

Log in to reply