use gtk::prelude::*; use gtk::{Application, ApplicationWindow, Button}; const APP_ID: &'static str = "org.gtk-rs.Gamarjoba"; fn main() { let app = Application::builder().application_id(APP_ID).build(); app.connect_activate(build_ui); app.run(); } fn build_ui(app: &Application) { let button = Button::builder() .label("Hit me!") .margin_top(12) .margin_bottom(12) .margin_start(12) .margin_end(12) .build(); button.connect_clicked(move |button| { button.set_label("Hahaha! Gay!"); }); let window = ApplicationWindow::builder() .application(app) .title("Gamarjoba from GTK4") .child(&button) .build(); window.present(); }