在Android中获得带有改进的对象数组

Question

private static Retrofit retrofit = null;

public static Retrofit getClient(String baseUrl) {
    if (retrofit==null) {
        retrofit = new Retrofit.Builder()
                .baseUrl(baseUrl)
                .addConverterFactory(GsonConverterFactory.create())
                .build();
    }
    return retrofit;
}

下面是使用我的GET方法的类：

public interface SOService {

    @GET("stocks/")
Call<List<Stock>> getStocks();

}

下面是我的类，包含url和如何连接：

public class ApiUtils {

    public static final String BASE_URL = "http://127.0.0.1:8000";

    public static SOService getSOService() {
        return RetrofitClient.getClient(BASE_URL).create(SOService.class);
    }
}

这就是我最终尝试获取信息的地方：

public class RegisterActivity extends AppCompatActivity {

    private Button registerButton;
    private SOService mService;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_register);

        mService = ApiUtils.getSOService();

        registerButton = findViewById(R.id.register_button);
        registerButton.setOnClickListener(v -> loadAnswers());
    }

    public void loadAnswers() {

        System.out.println("Entro aquí");
        mService.getStocks().enqueue(new Callback<List<Stock>>() {
        @Override
        public void onResponse(Call<List<Stock>> call, Response<List<Stock>> response) {
            if(response.isSuccessful()) {

                System.out.println("Te lo imprimo");
                System.out.println(response.body().toString());
                Log.d("MainActivity", "posts loaded from API");
            }else {
                int statusCode  = response.code();
                // handle request errors depending on status code
            }
        }

        @Override
        public void onFailure(Call<List<Stock>> call, Throwable t) {
            Log.d("MainActivity", "error loading from API");

        }
    });
    }
}

public class Stock {

    @SerializedName("id")
    @Expose
    private Integer id;
    @SerializedName("ticker")
    @Expose
    private String ticker;
    @SerializedName("open")
    @Expose
    private Double open;
    @SerializedName("close")
    @Expose
    private Double close;
    @SerializedName("volume")
    @Expose
    private Integer volume;

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getTicker() {
        return ticker;
    }

    public void setTicker(String ticker) {
        this.ticker = ticker;
    }

    public Double getOpen() {
        return open;
    }

    public void setOpen(Double open) {
        this.open = open;
    }

    public Double getClose() {
        return close;
    }

    public void setClose(Double close) {
        this.close = close;
    }

    public Integer getVolume() {
        return volume;
    }

    public void setVolume(Integer volume) {
        this.volume = volume;
    }

}

Answer 1

您应该尝试检索如下所示的对象列表：

public interface SOService {

    @GET("stocks/")
    Call<List<Stock>> getStocks();

}

mService.getStocks().enqueue(new Callback<List<Stock>>() {
            @Override
            public void onResponse(Call<List<Stock>> call, Response<List<Stock>> response) {
                if(response.isSuccessful()) {

                    System.out.println("Te lo imprimo");
                    System.out.println(response.body().toString());
                    Log.d("MainActivity", "posts loaded from API");
                }else {
                    int statusCode  = response.code();
                    // handle request errors depending on status code
                }
            }

            @Override
            public void onFailure(Call<List<Stock>> call, Throwable t) {
                Log.d("MainActivity", "error loading from API");

            }
        });

编辑

您正在尝试连接到计算机上的本地服务器，但通过模拟器。模拟器无法连接到此服务器。检查这个答案。您正在使用的本地URL将被改版用于识别您的电话（模拟器）上的本地端口和地址。这就是为什么你不能连接。你手机上没有那个地址的服务器。您需要输入您的pc ip地址，以便执行以下操作：）