- connect(ui->transition_btn1, SIGNAL(clicked()), mapper, SLOT(map()));
- connect(ui->transition_btn2, SIGNAL(clicked()), mapper, SLOT(map()));
- connect(ui->transition_btn3, SIGNAL(clicked()), mapper, SLOT(map()));
- connect(mapper, SIGNAL(mapped(int)), this, SLOT(transition_clicked(int)));
+ connect(ui->transition_btn1, &QPushButton::clicked, mapper, static_cast<void (QSignalMapper::*)()>(&QSignalMapper::map));
+ connect(ui->transition_btn2, &QPushButton::clicked, mapper, static_cast<void (QSignalMapper::*)()>(&QSignalMapper::map));
+ connect(ui->transition_btn3, &QPushButton::clicked, mapper, static_cast<void (QSignalMapper::*)()>(&QSignalMapper::map));
+ connect(mapper, static_cast<void (QSignalMapper::*)(int)>(&QSignalMapper::mapped), this, &MainWindow::transition_clicked);