Mvvm LIveData每次从Acity和以前的数据中观察两次以上

我遵循MVVM登录API，通过改进，我的问题是livedata被观察了两次以上，并且在从活动中观察时总是发出以前的响应，但在存储库中它给出了正确的响应 我从stackoverflow和其他网站尝试了很多解决方案，但仍然没有成功，我也尝试了删除观察员，但仍然获得了以前的数据，因此请建议一个可行的解决方案，我将在下面发布我的代码

LoginActivity.kt

private lateinit var loginViewModel: LoginViewModel

loginViewModel = ViewModelProvider(this, ViewModelProvider.NewInstanceFactory()).get(
            LoginViewModel::class.java
        )
loginViewModel.login(userEmail, pwd)

loginViewModel.getLoginRepository().observe(this, Observer {
    val loginResult = it ?: return@Observer
                     
    val accessToken = loginResult.user?.jwtToken.toString()

})
                    
val statusMsgObserver = Observer<String> { statusMsg ->
                        showToast(statusMsg)
                    })

val errorMsgObserver = Observer<String> { errorMsg ->
                        // Update the UI
                        showToast(errorMsg)
})

loginViewModel.getStatusMessage()?.observe(this, statusMsgObserver)

loginViewModel.getErrorStatusMessage()?.observe(this, errorMsgObserver)

在LoginActivity中，当我观察loginResult时，它首先给出先前发出的accessToken，然后再次调用，并给出当前accessToken，类似地，每次调用observer的次数超过两次。

---

但是在存储库中，它提供了最新的数据，请检查我的代码并建议我必须在哪里更正才能获得正确的最新livedata

最后我找到了解决方案，在LoginRepository中，我在doLogin（）外部声明了responseData，它应该在doLogin（）内部声明 由于不在方法范围内，它总是先给出以前的数据，然后给出当前的数据， 一旦我声明内部方法的问题已经解决，现在它的工作是完美的

class LoginViewModel: ViewModel() {

    private var loginRepository: LoginRepository? = null

    private var _mutableLiveData = MutableLiveData<LoginAPIResponse?>()
    val liveData: LiveData<LoginAPIResponse?> get() = _mutableLiveData

    private var responseMsgLiveData:MutableLiveData<String>?= null
    private var errorResponseMsgLiveData:MutableLiveData<String>?= null

    fun login(username: String, password: String) {

        loginRepository = LoginRepository.getInstance()!!

        /* Query data from Repository */
        //val _mutableLiveData: MutableLiveData<Response<LoginAPIResponse?>?>? = loginRepository?.doLogin(username, password)
        _mutableLiveData = loginRepository?.doLogin(username, password)!!

        responseMsgLiveData = loginRepository?.respMessage!!
        errorResponseMsgLiveData = loginRepository?.loginResponseErrorData!!
    }

    fun getLoginRepository(): LiveData<LoginAPIResponse?> {
        return liveData
    }

    fun getStatusMessage(): LiveData<String>? {
        return responseMsgLiveData
    }

    fun getErrorStatusMessage(): LiveData<String>? {
        return errorResponseMsgLiveData
    }
}

class LoginRepository {

    private val loginApi: ApiEndpoints = RetrofitService.createService(ApiEndpoints::class.java)

  
    val responseData = MutableLiveData<LoginAPIResponse?>()
    var respMessage = MutableLiveData<String>()
    var loginResponseErrorData = MutableLiveData<String>()

    fun doLogin(username: String, password: String)
    : MutableLiveData<LoginAPIResponse?> {

        respMessage.value = null
        loginResponseErrorData.value = null

        val params = JsonObject()
        params.addProperty("email", username)
        params.addProperty("password",password)
        val jsonParams = JsonObject()
        jsonParams.add("user",params)

        loginApi.loginToServer(jsonParams).enqueue(object : Callback<LoginAPIResponse?> {
            override fun onResponse( call: Call<LoginAPIResponse?>, response: Response<LoginAPIResponse?> ) {

                responseData.value = response.body()
                respMessage.value = RetrofitService.handleError(response.code())

                val error = response.errorBody()
                if (!response.isSuccessful) {
                    val errorMsg = error?.charStream()?.readText()
                    println("Error Message: $errorMsg")
                    loginResponseErrorData.value = errorMsg
                } else {
                    println("API Success -> Login, $username, ${response.body()?.user?.email.toString()}")
                }
            }

            override fun onFailure(call: Call<LoginAPIResponse?>, t: Throwable) {
                println("onFailure:(message) "+t.message)
                loginResponseErrorData.value = t.message
                responseData.value = null
            }
        })
        return responseData
    }

    companion object {
        private var loginRepository: LoginRepository? = null
        internal fun getInstance(): LoginRepository? {
            if (loginRepository == null) {
                loginRepository = LoginRepository()
            }
            return loginRepository
        }
    }
}

override fun onDestroy() {
        super.onDestroy()
        loginViewModel.getLoginRepository()?.removeObservers(this)
        this.viewModelStore.clear()
    }