#include "mainwindow.h" #include "ui_mainwindow.h" MainWindow::MainWindow(QWidget *parent) : QMainWindow(parent), ui(new Ui::MainWindow) { ui->setupUi(this); myButton = new QPushButton(this); myButton->setIcon(QIcon(":/res/icon128.png")); myButton->setIconSize(QSize(128, 128)); myButton->resize(QSize(128, 128)); connect(myButton, &QAbstractButton::clicked, this, &MainWindow::on_actionExit_triggered); } void MainWindow::closeEvent(QCloseEvent *event) { const QMessageBox::StandardButton ret = QMessageBox::warning(this, tr("Application"), tr("something-something-close?"), QMessageBox::Yes | QMessageBox::No); switch (ret) { case QMessageBox::Yes: event->accept(); break; case QMessageBox::No: default: event->ignore(); break; } } MainWindow::~MainWindow() { delete ui; delete myButton; } void MainWindow::on_actionExit_triggered() { exit(EXIT_SUCCESS); }