Show parent window

[Qt Coder]

Hello All,


I have developed one application,in which I m using 4-5 different screens to navigate.

Now from Mainwindow screen I have activated the another screen,so my mainwindow is now hidden .But in this new screen on one button click event I need to show the mainwindow screen .

How to acheive it???

The code I m using is as follows

in MainWindow.cpp

void MainWindow::f_Open_screen_al()
{	
	screen_al->show();
	screen_al->activateWindow();
}
 
void MainWindow::ShowMainWindow()
{	
	this->activateWindow();
}

void MainWindow::f_Open_screen_al()
{	
	screen_al->show();
	screen_al->activateWindow();
}

void MainWindow::ShowMainWindow()
{	
	this->activateWindow();
}

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and in screen_al.cpp

connect(ui.pushbutton, SIGNAL(clicked()), this->parent(), SLOT(ShowMainWindow()));

connect(ui.pushbutton, SIGNAL(clicked()), this->parent(), SLOT(ShowMainWindow()));

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But No mainwindow is displayed.....

Pls help