Add a custom widget in code to a MainWindow

[Steff]

Hy there,

i am new to Qt and Creator and have the following problem.

I whant to add an OpenGL QGLWidget to a QGuiApplication that i have created with the new project wizard. Then I add a new QTWidget (QT Designer Form Class) also over the wizard and change

class gl : public QWidget {

class gl : public QWidget {

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to

class gl : public QGLWidget {

class gl : public QGLWidget {

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in .h and .cpp

i alos add

#include "QGLWidget"

#include "QGLWidget"

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in the .h file

Now i need to create a new instance of my class here and connect it to the ui

GLTest::GLTest(QWidget *parent)
    : QMainWindow(parent), ui(new Ui::GLTest)
{
    // have to add it here
    ui->setupUi(this);
    // or here and how ?
}

GLTest::GLTest(QWidget *parent)
    : QMainWindow(parent), ui(new Ui::GLTest)
{
    // have to add it here
    ui->setupUi(this);
    // or here and how ?
}

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But i do not get it to work.
Can you give me an smale example?
I know that i have to add it to the CentraWidget.