How to avoid hidden QWidget height included in QStackedLayout? - qt

Question

I have this scenario with which I have been struggling for few hours:
I have a main widget, whose layout is set to main_layout, before which 3 layouts are added to the main_layout:
A QVBoxLayout (header_app_layout)
A second QVBoxLayout (header_loader_layout)
A QStackBoxLayout (content_layout)
The QStackBoxLayout (content_layout) has 2 child widgets added to it, of which only 1 is shown:
m_content1_widget (shown widget)
m_content2_widget
My problem is that, content_layout is taking into consideration the heights of the hidden child widgets in the widget: m_content1_widget, because of which the main_widget height is overflowing.
If I change content_layout from QStackedLayout to QVBoxLayout type, it all starts working fine.
So it seems to me that, QStackedLayout is respecting the height of the hidden widgets, which I don't want it to. Any ideas to overcome this ?
Here is the code:
main.cpp
int main(int argc, char* argv[])
{
QApplication app(argc, argv);
main_widget w;
w.setFixedSize(400, 400);
w.show();
return app.exec();
}
main_widget.h
#include <QWidget>
#include <QLabel>
#include <QStackedLayout>
#include <QVBoxLayout>
#include <QPushButton>
class main_widget : public QWidget
{
Q_OBJECT
public:
main_widget();
};
main_widget.cpp
#include "main_widget.h"
main_widget::main_widget()
: QWidget(nullptr)
{
QVBoxLayout *header_app_layout = new QVBoxLayout();
QLabel *header_app_label = new QLabel();
header_app_label->setText(tr("Header"));
header_app_layout->addWidget(header_app_label);
QVBoxLayout* header_loader_layout = new QVBoxLayout();
QLabel* header_loader_label = new QLabel();
header_loader_label->setText(tr("Header Loader"));
header_loader_layout->addWidget(header_loader_label);
QWidget *m_content1_widget = new QWidget();
QVBoxLayout* content1_layout = new QVBoxLayout(m_content1_widget);
QPushButton* content1_button1 = new QPushButton(tr("content1_button1"));
content1_layout->addWidget(content1_button1);
QPushButton* content1_button2 = new QPushButton(tr("content1_button2"));
content1_layout->addWidget(content1_button2);
QPushButton* content1_button3 = new QPushButton(tr("content1_button3"));
content1_layout->addWidget(content1_button3);
content1_button2->hide(); //Hidden for now. But it's height is being included
content1_button3->hide();
QWidget* m_content2_widget = new QWidget();
QVBoxLayout* content2_layout = new QVBoxLayout(m_content2_widget);
QPushButton* content2_button1 = new QPushButton(tr("content2_button1"));
content2_layout->addWidget(content2_button1);
QPushButton* content2_button2 = new QPushButton(tr("content2_button2"));
content2_layout->addWidget(content2_button2);
QPushButton* content2_button3 = new QPushButton(tr("content2_button3"));
content2_layout->addWidget(content2_button3);
content2_button2->hide();
content2_button3->hide();
QStackedLayout* content_layout = new QStackedLayout(); //Doesn't work
//QVBoxLayout *content_layout = new QVBoxLayout(); //Works, but I need it to be of type `QStackedLayout` to show the 2 child widgets conditionally
content_layout->addWidget(m_content1_widget);
content_layout->addWidget(m_content2_widget);
content_layout->setStackingMode(QStackedLayout::StackingMode::StackOne);
content_layout->setCurrentIndex(0);
QVBoxLayout* main_layout = new QVBoxLayout;
main_layout->addLayout(header_app_layout); //Adding a QVBoxLayout
main_layout->addLayout(header_loader_layout); //Adding another QVBoxLayout
main_layout->addSpacing(32);
main_layout->addLayout(content_layout); //Adding the QStackedLayout
this->setLayout(main_layout);
}

Answer 1

I was able to resolve the issue by calling adjustSize on m_content2_widget, which removed the space occupied by the hidden controls inside m_content2_widget.
m_content2_widget->adjustSize();