My app doesn’t display the data from an API with retrofit and moshi

I am a beginning computer schience student. For school I have to make an app that can display data from an API. I use this API: The user of my app has to enter a booktitle or author, so they can find a book. I add the search value to the url. For example, if I want to search “The hobbit”, the url would look like this:”. However, the data does not get displayed. I don’t have any errors either. Is there anyone that can help me?
Thanks in advance!

My API service class

private const val BASE_URL = ""

private val moshi = Moshi.Builder()

private val retrofit = Retrofit.Builder()

interface BoekenAPIService {
    suspend fun getBooksByTitle(@Query("q")search: String) : Base_BookTitle

object BookAPI {
    val retrofitService : BoekenAPIService by lazy { retrofit.create( }

My Base_BookTitle class

data class Base_BookTitle (
    val numFound : Int,
    val start : Int,
    val numFoundExact : Boolean,
    val docs : List<Q>,
    val num_found : Int,
    val book : String,
    val offset : String

My Q class

data class Q (
    val key : String,
    val type : String,
    val seed : List<String>,
    val title : String,
    val title_suggest : String,
    val has_fulltext : Boolean,
    val edition_count : Int,
    val edition_edition_key : List<String>,
    val publish_date : List<String>,
    val publish_year : List<Int>,
    val first_publish_year : Int,
    val number_of_pages_median : Int,
    val lccn : List<Int>,
    val publish_place : List<String>,
    val oclc : List<Int>,
    val contributor : List<String>,
    val lcc : List<String>,
    val ddc : List<Double>,
    val isbn : List<Int>,
    val last_modified_i : Int,
    val ebook_count_i : Int,
    val ia : List<String>,
    val public_scan_b : Boolean,
    val ia_collection_s : String,
    val lending_edition_s : String,
    val lending_identifier_s : String,
    val printdisabled_s : String,
    val cover_edition_cover_edition_key : String,
    val cover_i : Int,
    val publisher : List<String>,
    val language : List<String>,
    val author_author_key : List<String>,
    val author_name : List<String>,
    val author_alternative_name : List<String>,
    val person : List<String>,
    val place : List<String>,
    val subject : List<String>,
    val time : List<String>,
    val id_alibris_id : List<Int>,
    val id_amazon : List<String>,
    val id_canadian_national_library_archive : List<Int>,
    val id_depósito_legal : List<String>,
    val id_goodreads : List<Int>,
    val id_google : List<String>,
    val id_librarything : List<Int>,
    val id_overdrive : List<String>,
    val id_paperback_swap : List<Int>,
    val id_wikidata : List<String>,
    val ia_loaded_id : List<String>,
    val ia_box_id : List<String>,
    val publisher_facet : List<String>,
    val person_person_key : List<String>,
    val place_place_key : List<String>,
    val time_facet : List<String>,
    val person_facet : List<String>,
    val subject_facet : List<String>,
    val _version_ : Int,
    val place_facet : List<String>,
    val lcc_sort : String,
    val author_facet : List<String>,
    val subject_subject_key : List<String>,
    val ddc_sort : Double,
    val time_time_key : List<String>
): Parcelable

I got the Base_Booktitle and Q class from a json to kotlin converter.

The ViewModel in which i call the method to display the data

class SearchViewModel(__user: User) : ViewModel() {
   var _user = MutableLiveData<User>()
   val user:LiveData<User>
       get() {
           return _user
   var _baseBookTitle = MutableLiveData<Base_BookTitle?>()
   val baseBooktitle : LiveData<Base_BookTitle?>
   get() {
       return _baseBookTitle
   var search = MutableLiveData<String>()
   var _error = MutableLiveData<String>()
   val error : LiveData<String>
   get() {
       return _error
   var _response = MutableLiveData<Q?>()
   val response: LiveData<Q?>
       return _response
   init {
       _user.value = __user
       _error.value = null

   fun searchBtnClicked(){
       viewModelScope.launch {
               _baseBookTitle.value = BookAPI.retrofitService.getBooksByTitle(search.value!!)
           catch (e: Exception){
               _error.value = e.localizedMessage
   fun onBookClicked(book: Q){
       _response.value = book
   fun navigateToBookFinished(){
       _response.value = null


La mascarade s'arrête là : le slalom de Zagreb définitivement annulé thumbnail

La mascarade s’arrête là : le slalom de Zagreb définitivement annulé

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