This is all that is needed to write a QML application in Rust with CXX-Qt now:
```
fn main() {
let mut app = QGuiApplication::new();
let mut engine = QQmlApplicationEngine::new();
if let Some(engine) = engine.as_mut() {
engine.load(&QUrl::from("qrc:/main.qml"));
}
if let Some(app) = app.as_mut() {
app.exec();
}
}
```