springboot和ionic如何通信？

Question

i am using ionic 4 with spring boot web service, the problem is after installation application in my phone the web service is not run?

i use in Controller.java

@CrossOrigin(origins = "*")
@RestController
public class CarController {
    @Autowired
    CarRepository carRepository;
    
    @GetMapping(path = "/cars")
    public ResponseEntity<List<Car>> retriveCars() {
        try {
            List<Car> cars = new ArrayList<>();
            carRepository.findAll().forEach(cars::add);
            
            
            if (cars.isEmpty()) {
                return new ResponseEntity<>(null, HttpStatus.NO_CONTENT);
            }
            return new ResponseEntity<>(cars, HttpStatus.OK);
        }catch(Exception e) {
            return new ResponseEntity<>(null, HttpStatus.INTERNAL_SERVER_ERROR);
        }
    }
    
    @PostMapping(path = "/car")
    public ResponseEntity<Car> saveCar (@RequestBody Car car) {
        try {
            Car _car= carRepository.save(new Car(UUID.randomUUID(), car.getMake(), car.getModel()));
            return new ResponseEntity<>(_car, HttpStatus.CREATED);
        }
        catch(Exception e) {
            System.out.println(e);
            return new ResponseEntity<>(null, HttpStatus.EXPECTATION_FAILED);
            
        }
    }

and in api.service.ts

 import { Injectable } from '@angular/core';
import { HttpClient } from '@angular/common/http'
import { Car } from './car';

@Injectable({
  providedIn: 'root'
})
export class ApiService {
  constructor(private http: HttpClient) { }

  baseUrl='http://localhost:8081';

  retrieveCars(){
    return this.http.get<Car[]>(this.baseUrl+ '/cars');
  }

  saveCar(car: Car) {
    return this.http.post<Car>(this.baseUrl+'/car', car);
  }

My question is how can i communicate in ionic and springboot? i need help please

Answer 1

yes it will not work because http gives mixed data in mobiles and emulators.... it will work perfectly with browsers but not with emulators and devices

Solution is simple just use https to get data in api.service.ts in baseUrl everything else is fine

https ://localhost:8081

baseUrl='http://localhost:8081';