C++ (Qt)
class MyClass {
public:
    void Connect() {
        ...
    }
 
private:
    ...
};

C++ (Qt)
#include <QWidget>
 
 class MyWidget : public QWidget
 {
 public:
     MyWidget(QWidget *parent = 0);
 };

ui->

ui->textEdit->setText("текст");

C++ (Qt)
QTextEdit edit;
edit.setReadOnly(true);
edit.insertPlainText("text");

C++ (Qt)
#include "widget.h"
#include "ui_widget.h"
 
#include <QApplication>
#include <QAxObject>
#include <QAxWidget>
#include <QtWidgets>
#include <QString>
 
Widget::Widget(QWidget *parent)
    : QWidget(parent)
    , ui(new Ui::Widget)
{
    ui->setupUi(this);
}
 
Widget::~Widget()
{
    delete ui;
}
 
 
int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
 
    Widget mainWindow;
    mainWindow.setWindowTitle("qwerty");
 
    QVBoxLayout layout(&mainWindow);
 
    mainWindow.show();
    return a.exec();
}
 
void Widget::on_pushButton_clicked()
{
    this->close();
}