Delay in Between loading windows In Qt

[vishnu717]

Hello


I am Beginner to Qt


I used to navigate windows By creating object of that window and hiding the present window . But the Loading time is about 6 seconds . I wanted to get rid of this.
Here is My code of creating Object of Window

void startWindow::on_english_clicked()
{
 
 
    MainWindow *other = new MainWindow;
    other->ui->tester->hide();
    other->ui->textBrowser->hide();
    other->ui->frame_2->hide();
    other->show();
    this->hide();
}

void startWindow::on_english_clicked()
{


    MainWindow *other = new MainWindow;
    other->ui->tester->hide();
    other->ui->textBrowser->hide();
    other->ui->frame_2->hide();
    other->show();
    this->hide();
}

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this is the code in Loading the mainwindow and below is code that is redirected again to the startwindow ..

void MainWindow::on_backward_clicked()
{
    videoplayer->stop();
    videoplayer->hide();
    startWindow *start=new startWindow;
    start->show();
    this->close();
    this->deleteLater();
 
 
}

void MainWindow::on_backward_clicked()
{
    videoplayer->stop();
    videoplayer->hide();
    startWindow *start=new startWindow;
    start->show();
    this->close();
    this->deleteLater();


}

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[stampede]

Have you tried not to create new / delete windows and just create once and later only hide / show them ?
I think you are creating a memory leak, because objects of class startWindow may not be deleted, you just hide() them and later you create new object without parent set. Imagine this sequence:
- open start window, click "english" (start window 1 hides)
- in mainWindow, click "backward" (start window 2 created)
- in start window 2, click "english" ( start window 2 hidden )
- continue with above steps ...
Looks like startWindows are created and hidden but never deleted, I can't be sure, maybe somewhere else you delete them.
If creating the widgets takes so much time, you can do that once, for example in startWindow constructor:

startWindow::startWindow( QWidget * parent ) : ...
{
 ...
 this->_mainWindow = new MainWindow; // create and store mainWindow object
 this->_mainWindow->setStartWindow( this ); // here you can pass a pointer to this object
                                                              // in order to show this window later
}
 
// you can keep startWindow pointer as a member in mainWindow class
void MainWindow::setStartWindow( startWindow * s ){
    this->_startWindow = s;
}
 
// now your methods looks simpler
void startWindow::on_english_clicked()
{
  //  MainWindow *other = new MainWindow; // no need to create new object each time
    _mainWindow->ui->tester->hide();
    _mainWindow->ui->textBrowser->hide();
    _mainWindow->ui->frame_2->hide();
    _mainWindow->show();
    this->hide();
}
 
void MainWindow::on_backward_clicked()
{
    videoplayer->stop();
    videoplayer->hide();
//    startWindow *start=new startWindow;
    this->_startWindow->show();
    this->close();
}

startWindow::startWindow( QWidget * parent ) : ...
{
 ...
 this->_mainWindow = new MainWindow; // create and store mainWindow object
 this->_mainWindow->setStartWindow( this ); // here you can pass a pointer to this object
                                                              // in order to show this window later
}

// you can keep startWindow pointer as a member in mainWindow class
void MainWindow::setStartWindow( startWindow * s ){
    this->_startWindow = s;
}

// now your methods looks simpler
void startWindow::on_english_clicked()
{
  //  MainWindow *other = new MainWindow; // no need to create new object each time
    _mainWindow->ui->tester->hide();
    _mainWindow->ui->textBrowser->hide();
    _mainWindow->ui->frame_2->hide();
    _mainWindow->show();
    this->hide();
}

void MainWindow::on_backward_clicked()
{
    videoplayer->stop();
    videoplayer->hide();
//    startWindow *start=new startWindow;
    this->_startWindow->show();
    this->close();
}

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This way you can avoid creating new widgets each time.