Create a widget using QStackedLayout

Question

Hi everyone I'm pretty new to programming with Qt and I would like to create a widget using a QStackedLayout. I already designed some widgets with Qt Creator, added them to the QStackedLayout and set it to the main widget. But now I would like to change the widgets using buttons inside the added widgets using the setCurrentIndex method. Now I have to use the connect function but in the main widget class I can't access components from the other widgets to connect them. So how can I do this?

#include "mainwindowwidget.h"
#include "ui_mainwindowwidget.h"


MainWindowWidget::MainWindowWidget(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::MainWindowWidget)
{


    qApp->setStyleSheet("MainWindowWidget {background-color : red}");

    //initializing widgets
    this->mainWidget_ = new MainWidget;
    this->createGameWidget_ = new CreateGameWidget;
    this->widgets_ = new QStackedLayout;


    //adding widgets to QstackedLayout
    this->widgets_->addWidget(this->mainWidget_);
    this->widgets_->addWidget(this->createGameWidget_);

    this->setLayout(this->widgets_);
    this->showFullScreen();
    // I would like to connect the qstackedlayout
    // = widgets_ with a button placed in mainwidget_
    ui->setupUi(this);

}

MainWindowWidget::~MainWindowWidget()
{
    delete ui;
}

Answer 1

You have a few options here. If your button is a public member of MainWidget, then you can simply connect the button's clicked() signal to your slot in MainWindow.

//mainwindow.h
...
public slots:
   void buttonClicked();

 

//mainwindow.cpp
...
   connect(mainWidget_->button, SIGNAL(clicked()), this, SLOT(buttonClicked()));
...
void buttonClicked()
{
   //do what you want to do here...
}

Another option is to create a custom signal in your MainWidget class. Then connect your button's clicked() signal to this custom signal:

//mainwidget.h
...
signals:
   void buttonClickedSignal();

 

//mainwidget.cpp
   connect(button, SIGNAL(clicked()), this, SIGNAL(buttonClickedSignal()));

Then connect your buttonClickedSignal() signal to a slot in your MainWindow:

//mainwindow.cpp
   connect(mainWidget_, SIGNAL(buttonClickedSignal()), this, SLOT(buttonClicked()));

A third option would be to add a function to your MainWidget class, that returns a pointer to your button. Then call this function in your MainWindow class, and use that pointer to connect your button to a slot.

//mainwidget.h
...
public:
   QPushButton* getButton();
...

  

//mainwdiget.cpp
...
QPushButton* getButton()
{
   return button;
}
...

 

//mainwindow.cpp
...
   QPushButton *button = mainWidget_->getButton();
   connect(button, SIGNAL(clicked()), this, SLOT(buttonClicked()));