定义Retrofit Service类

import android.os.Build
import cn.wtyc.weiwogroup.global.Constant
import cn.wtyc.weiwogroup.global.MyApplication
import cn.wtyc.weiwogroup.mvvm.utils.logV
import com.google.gson.GsonBuilder
import okhttp3.*
import retrofit2.Retrofit
import retrofit2.converter.gson.GsonConverterFactory
import retrofit2.converter.scalars.ScalarsConverterFactory
import java.io.IOException
import java.util.Date


/**
 * 网络基础服务配置。
 * @author ym6745476
 * @since  2021/10/14
 */
object RetrofitService {

    const val BASE_URL = "https://127.0.0.1/"

    val httpClient: OkHttpClient = OkHttpClient.Builder()
        .addInterceptor(LoggingInterceptor())
        .addInterceptor(HeaderInterceptor())
        .addInterceptor(BasicParamsInterceptor())
        .build()

    private val builder = Retrofit.Builder()
        .baseUrl(BASE_URL)
        .client(httpClient)
        .addConverterFactory(ScalarsConverterFactory.create())
        .addConverterFactory(GsonConverterFactory.create(GsonBuilder().registerTypeAdapterFactory(
            GsonTypeAdapterFactory()
        ).create()))

    private val retrofit = builder.build()

    fun <T> create(serviceClass: Class<T>): T = retrofit.create(serviceClass)


    class LoggingInterceptor : Interceptor {

        @Throws(IOException::class)
        override fun intercept(chain: Interceptor.Chain): Response {
            val request = chain.request()
            val t1 = System.nanoTime()

            //logV(TAG, "发送请求: ${request.method()} ${request.url()} ${request.headers()}")

            logV(
                TAG,String.format("发送请求 %s on %s%n%s",
                request.url(), request.method(), request.headers()));

            val response = chain.proceed(request)

            val t2 = System.nanoTime()
            //logV(TAG, "Received response for  ${response.request().url()} in ${(t2 - t1) / 1e6} ms\n${response.headers()}")
            val responseBody: ResponseBody = response.peekBody((1024 * 1024).toLong())
            logV(
                TAG,
                String.format(
                    "接收响应: [%s] %n返回json:【%s】 %.1fms%n%s",
                    response.request().url(),
                    responseBody.string(),
                    (t2 - t1) / 1e6,
                    response.headers()
                )
            )

            return response
        }

        companion object {
            const val TAG = "LoggingInterceptor"
        }
    }

    class HeaderInterceptor : Interceptor {
        override fun intercept(chain: Interceptor.Chain): Response {
            val original = chain.request()
            val request = original.newBuilder().apply {
                header("model", "Android")
                header("If-Modified-Since", "${Date()}")
                header("User-Agent", System.getProperty("http.agent") ?: "unknown")
                header("token", "传入你的token")
            }.build()
            return chain.proceed(request)
        }
    }

    class BasicParamsInterceptor : Interceptor {
        override fun intercept(chain: Interceptor.Chain): Response {
            val originalRequest = chain.request()
            val originalHttpUrl = originalRequest.url()
            val url = originalHttpUrl.newBuilder().apply {
                addQueryParameter("version", "${Build.VERSION.SDK_INT}")
            }.build()
            val request = originalRequest.newBuilder().url(url).method(originalRequest.method(), originalRequest.body()).build()
            return chain.proceed(request)
        }
    }
}

定义TypeAdapterFactory

/**
 * Gson解析
 * @author ym6745476
 * @since  2021/10/14
 */
class GsonTypeAdapterFactory : TypeAdapterFactory {

    override fun <T : Any?> create(gson: Gson?, type: TypeToken<T>?): TypeAdapter<T> {
        val adapter = gson?.getDelegateAdapter(this, type)
        return object : TypeAdapter<T>() {
            @Throws(IOException::class)
            override fun write(out: JsonWriter?, value: T) {
                adapter?.write(out, value)
            }

            @Throws(IOException::class)
            override fun read(jr: JsonReader): T? {
                return try {
                    adapter?.read(jr)
                } catch (e: Throwable) {
                    e.printStackTrace()
                    consumeAll(jr)
                    null
                }
            }

            @Throws(IOException::class)
            private fun consumeAll(jr: JsonReader) {
                if (jr.hasNext()) {
                    val peek: JsonToken = jr.peek()
                    when {
                        peek === JsonToken.STRING -> {
                            jr.nextString()
                        }
                        peek === JsonToken.BEGIN_ARRAY -> {
                            jr.beginArray()
                            consumeAll(jr)
                            jr.endArray()
                        }
                        peek === JsonToken.BEGIN_OBJECT -> {
                            jr.beginObject()
                            consumeAll(jr)
                            jr.endObject()
                        }
                        peek === JsonToken.END_ARRAY -> {
                            jr.endArray()
                        }
                        peek === JsonToken.END_OBJECT -> {
                            jr.endObject()
                        }
                        peek === JsonToken.NUMBER -> {
                            jr.nextString()
                        }
                        peek === JsonToken.BOOLEAN -> {
                            jr.nextBoolean()
                        }
                        peek === JsonToken.NAME -> {
                            jr.nextName()
                            consumeAll(jr)
                        }
                        peek === JsonToken.NULL -> {
                            jr.nextNull()
                        }
                    }
                }
            }
        }
    }
}

定义Service

interface RecordService {

    @GET("/api/list")
    suspend fun list(@Query("page") page:Int,@Query("pageSize") pageSize:Int): ServiceResult<RecordItem>
}

在Repository中定义

private var service = RetrofitService.create(RecordService:class.java)

suspend fun getList(size: Int): ServiceResult<RecordItem> {
      return service.list(size)
}

配置Retrofit Get方式

@GET("/api/list")
suspend fun list(@Query("page") page:Int,@Query("pageSize") pageSize:Int): ServiceResult<RecordItem>

配置Retrofit Post Form方式

@FormUrlEncoded
@POST("/api/list")
suspend fun list(@Field("name")  name:String): ServiceResult<RecordItem>

配置Retrofit Post Json方式

@Headers("Content-Type: application/json", "Accept: */*")
@POST("api/login")
suspend fun login(@Body data: RequestBody): ServiceResult<LoginUser>

var data = HashMap<String,String>()
data.put("mobile",mobile)
data.put("password",password)
val paramBody = RequestBody.create(MediaType.parse("application/json;charset=UTF-8"),Gson().toJson(data))
val response = userService.login(paramBody)

以上。