Я пытаюсь переписать навигационную кнопку «Назад» в соответствии с моими потребностями в Android с помощью ionic 3, но всякий раз, когда я запускаю свое приложение, при нажатии кнопки «Назад» навигационная кнопка говорит: «nav.getActive - это не функция» из-за этой ошибки.Кнопка не работает.
Обновлен следующий код
export class MyApp {
rootPage:any = LoginPage;
public counter=0;
@ViewChild(Nav) nav: Nav;
constructor(platform: Platform, statusBar: StatusBar, splashScreen: SplashScreen,public globalProvider: GlobalProvider,
public googlePlus: GooglePlus, public zone: NgZone, private readonly firebase: Firebase, private alertCtrl: AlertController,
public toastCtrl: ToastController, public app: App) {
platform.ready().then(() => {
// Okay, so the platform is ready and our plugins are available.
// Here you can do any higher level native things you might need.
statusBar.styleDefault();
splashScreen.hide();
platform.registerBackButtonAction(() => {
const activeView = this.nav.getActive().name // This will give you the activeview name
if(activeView === 'HomePage') {
if (this.nav.canGoBack()){ //Can we go back?
this.nav.pop();
} else {
const alert = this.alertCtrl.create({
title: 'App termination',
message: 'Do you want to close the app?',
buttons: [{
text: 'Cancel',
role: 'cancel',
handler: () => {
console.log('Application exit prevented!');
}
},{
text: 'Close App',
handler: () => {
platform.exitApp(); // Close this application
}
}]
});
alert.present();
}
}
this.nav.push(TabsPage);
}, 1);
this.firebase.onNotificationOpen().subscribe(notification => {
console.log('notification info: ', notification);
/*!notification.tap
? console.log('The user was using the app when the notification arrived...')
: console.log('The app was closed when the notification arrived...');
let notificationAlert = this.alertCtrl.create({
title: notification.title,
message: notification.body,
buttons: ['Ok']
});
notificationAlert.present();*/
},
error => {
console.error('Error getting the notification', error);
});
});
/*platform.registerBackButtonAction(() => {
if (this.counter == 0) {
this.counter++;
this.presentToast();
setTimeout(() => { this.counter = 0 }, 3000)
} else {
// console.log("exitapp");
platform.exitApp();
}
}, 0) });*/
}