How to add widget to QScrollArea

[Pradeep Kumar]

Hi,

I am trying to add widget to QScrollarea,
i am getting scrollbars, but widget is not visible in QScrollarea, but it is behind QScrollarea,

Sample code,

m_pQWidget = new QWidget;
m_pQWidget->setFixedSize(2000,2000);

m_pQScrollArea = new QScrollArea;
m_pQScrollArea->setWidgetResizable(true);
m_pQScrollArea->setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOn);
m_pQScrollArea->setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOn);

m_pQVBoxLayoutMain = new QVBoxLayout;


m_pQScrollArea->setWidget(m_pQWidget);


m_pQVBoxLayoutMain->addWidget(m_pQScrollArea);
setLayout(m_pQVBoxLayoutMain);

And the output, is provided in the link, the widget is behind scrollarea,

https://i.imgsafe.org/0740452093.png

can u provide guidance, on how can i achieve this?.

Thanks,

[koahnig]

@Pradeep-Kumar

Did you try to populate your widget?

I had added recently QScrollArea using designer. The generated ui file has basically the steps you mention. However, before setting the widget with setWidget there are all the steps for population of the widget.

Hope this helps.

[Pradeep Kumar]

Without scrollarea, i am getting the widget displayed,
but i want inside QScrollarea,

How can i add QWidget inside QScrollArea, am i doing any wrong in the above code posted, any modifications needed?.

Thanks,

[Ni.Sumi]

@Pradeep-Kumar

I have tried in the sample program using your code . It worked , use some qDebug's to get exact info.

MainWindow::MainWindow(QWidget* parent) :
  QMainWindow(parent),
  ui(new Ui::MainWindow) {
  ui->setupUi(this);

  QWidget* my = new QWidget(this); //Widget
  my->setFixedSize(2000, 2000);
  my->setStyleSheet("background-color: yellow ");

  QScrollArea* m_pQScrollArea = new QScrollArea;
  m_pQScrollArea->setWidget(my);

  m_pQScrollArea->setWidgetResizable(true);
  m_pQScrollArea->setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOn);
  m_pQScrollArea->setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOn);
  
  QVBoxLayout* m_pQVBoxLayoutMain = new QVBoxLayout;
  m_pQVBoxLayoutMain->addWidget(m_pQScrollArea);

  QWidget* central = new QWidget(this);
  central->setLayout(m_pQVBoxLayoutMain);
  setCentralWidget(central);
}

Edit:

USe some back ground color for the Widget, it helps to know whether it got added or not. Currently , it si empty widget , not possible to see .

[Pradeep Kumar]

i will try .

can u post the image please, which you got the output @Ni.Sumi.

Thanks,

[Ni.Sumi]

@Pradeep-Kumar

Ofcourse, _here it is.


[Pradeep Kumar]

@Ni.Sumi

image is not attached, i cant see.

[Ni.Sumi]

@Pradeep-Kumar

https://postimg.org/image/i4uo77l23/

[Pradeep Kumar]

@Ni-Sumi

Thanks for the answer.

can u give me sample inheriting QWidget,
how can it be done.?.

Thanks,

[Ni.Sumi]

@Pradeep-Kumar

Is this way?

#include "widget.h"
#include "ui_widget.h"
#include <QVBoxLayout>
#include <QScrollArea>

Widget::Widget(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::Widget)
{
    ui->setupUi(this);

    QWidget* my = new QWidget(this); //Widget
    my->setFixedSize(2000, 2000);
    my->setStyleSheet("background-color: yellow ");

    QScrollArea* m_pQScrollArea = new QScrollArea;
    m_pQScrollArea->setWidget(my);

    m_pQScrollArea->setWidgetResizable(true);
    m_pQScrollArea->setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOn);
    m_pQScrollArea->setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOn);

    QVBoxLayout* m_pQVBoxLayoutMain = new QVBoxLayout;
    m_pQVBoxLayoutMain->addWidget(m_pQScrollArea);

    setLayout(m_pQVBoxLayoutMain);
}

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

https://postimg.org/image/4bspfhlkf/

It's the same , in the place of setCentralWidget() , we need setLAyout()

[Taz742]

@Pradeep-Kumar
I think the problem has been solved.
Mark as solved.