Koin + Retrofit 在运行时添加标题

Question

我有一个基于 MVVM 架构的硬币和改造项目。我想在注册此项目后使用“viewmodel”打印数据并在运行时将“token”的值添加到标题中。 但我无法提供获取我保存在 SharedPreferences 中的令牌所需的上下文结构。我怎样才能以最干净的形式处理它？

 fun createNetworkClient(baseUrl: String) =
        retrofitClient(baseUrl, httpClient())


    private fun httpClient(): OkHttpClient {

        val httpLoggingInterceptor = HttpLoggingInterceptor(HttpLoggingInterceptor.Logger.DEFAULT)
        val clientBuilder = OkHttpClient.Builder()
        if (BuildConfig.DEBUG) {
            httpLoggingInterceptor.level = HttpLoggingInterceptor.Level.BODY
            clientBuilder.addInterceptor(httpLoggingInterceptor)
        }
        clientBuilder.addInterceptor { chain ->
            val newRequest = chain.request().newBuilder()
                .addHeader( //I can't get token because there is no context here.
                    "Authorization", "Bearer ${PreferencesHelper.getInstance(context).token.toString()}"
                )
                .build()
            chain.proceed(newRequest)
        }



        clientBuilder.readTimeout(120, TimeUnit.SECONDS)
        clientBuilder.writeTimeout(120, TimeUnit.SECONDS)
        return clientBuilder.build()
    }

    private fun retrofitClient(baseUrl: String, httpClient: OkHttpClient): Retrofit =
        Retrofit.Builder()
            .baseUrl(baseUrl)
            .client(httpClient)
            .addConverterFactory(GsonConverterFactory.create())
            .addCallAdapterFactory(RxJava2CallAdapterFactory.create())
            .build()

应用模块

val appModule = module {
    single {
        androidApplication().getSharedPreferences("PREFERENCES", android.content.Context.MODE_PRIVATE)
    }
    single { createNetworkClient(BuildConfig.BASE_URL) }
    single { (get() as Retrofit).create(Api::class.java) } 
    viewModel {
        ContactViewModel(get())
    }
}

我的联系活动

 private val contactList: ContactViewModel  by viewModel()
    override fun onCreate(savedInstanceState: Bundle?) {
        viewModel = contactList

        super.onCreate(savedInstanceState)
        binding.adapter = ContactAdapter(this)
        binding.layoutManager = LinearLayoutManager(this)

        contactList.getContactList()

        contactList.contactListLiveData.observe(this, Observer { list ->
            if (list != null)
                binding.adapter?.update(list)
        })
    }

Answer 1

您可以创建一个 Koin 模块来提供共享首选项：

val sharedPreferencesModule = module {

   single {
      androidApplication().getSharedPreferences("PREFERENCES",  android.content.Context.MODE_PRIVATE)
   }
}

然后用 Koin 将其注入到生成 Retrofit 客户端的类中。

编辑

你需要修改你的createNetworkClient方法签名：

fun createNetworkClient(baseUrl: String, preferences: SharedPreferences)

然后用 Koin 注入它：

val appModule = module {
    single {
        androidApplication().getSharedPreferences("PREFERENCES", android.content.Context.MODE_PRIVATE)
    }
    single { createNetworkClient(BuildConfig.BASE_URL, get()) }

    ...
}

然后您将收到在createNetworkClient 方法中注入的共享首选项，并且只需要实现从共享首选项中检索令牌的逻辑。