If I want to use "setCentralWidget" in Widget, what should I do.

[Sabual]

I am now porting the sample code of QCustomPlot. The sample code of QCustomPlot uses QMainWindow, and I want to use QWidget. What should I do?

this is my code

Widget::Widget(QWidget *parent)
    : QWidget(parent)
    , ui(new Ui::Widget),
      mPlot(0),
      mTag1(0),
      mTag2(0)
{
    ui->setupUi(this);

    mPlot = new QCustomPlot(this);
    setCentralWidget(mPlot);
}

this is QCustomPlot`s sample code

MainWindow::MainWindow(QWidget *parent) :
  QMainWindow(parent),
  ui(new Ui::MainWindow),
  mPlot(0),
  mTag1(0),
  mTag2(0)
{
  ui->setupUi(this);
  
  mPlot = new QCustomPlot(this);
  setCentralWidget(mPlot);
}

Please help me!😭😭

[skycrestway]

You can only use setCentralWidget with a QMainWindow. Instead use QWidget::setLayout to add a layout and then add a QWidget to the layout.

See the documentation for QWidget::setLayout.

[Sabual]

The QWidget is a separate ‘.ui’ file.

[SGaist]

Hi and welcome to devnet,

The answer of @skycrestway still holds. Your widget needs a layout. After that you can add your plot to that layout.

[Sabual]

@SGaist oh!i know，thanks！