预期开始数组但在 Retrofit 调用中是开始对象

Question

一开始我必须说我是Android中的新手。我想用 Retrofit 进行调用，但调用时出现错误：Expected begin array but was begin object.

我正在尝试解析 result，然后在 RecyclerView 中显示它。下面是我的适配器、activity、POJO 和接口文件。在此先感谢您的帮助。

例子

    public class Example {

    @SerializedName("pagination")
    @Expose
    private Pagination pagination;
    @SerializedName("results")
    @Expose
    private List<Result> results = null;

    public Pagination getPagination() {
        return pagination;
    }

    public void setPagination(Pagination pagination) {
        this.pagination = pagination;
    }

    public List<Result> getResults() {
        return results;
    }

    public void setResults(List<Result> results) {
        this.results = results;
    }

}

结果

    public class Result {
    
    @SerializedName("country")
    @Expose
    private String country;
    @SerializedName("year")
    @Expose
    private String year;
    @SerializedName("format")
    @Expose
    private List<String> format = null;
    @SerializedName("label")
    @Expose
    private List<String> label = null;
    @SerializedName("type")
    @Expose
    private String type;
    @SerializedName("genre")
    @Expose
    private List<String> genre = null;
    @SerializedName("style")
    @Expose
    private List<String> style = null;
    @SerializedName("id")
    @Expose
    private Integer id;
    @SerializedName("barcode")
    @Expose
    private List<String> barcode = null;
    @SerializedName("master_id")
    @Expose
    private Integer masterId;
    @SerializedName("master_url")
    @Expose
    private String masterUrl;
    @SerializedName("uri")
    @Expose
    private String uri;
    @SerializedName("catno")
    @Expose
    private String catno;
    @SerializedName("title")
    @Expose
    private String title;
    @SerializedName("thumb")
    @Expose
    private String thumb;
    @SerializedName("cover_image")
    @Expose
    private String coverImage;
    @SerializedName("resource_url")
    @Expose
    private String resourceUrl;
    @SerializedName("community")
    
    
    public String getCountry() {
        return country;
    }
    
    public void setCountry(String country) {
        this.country = country;
    }
    
    public String getYear() {
        return year;
    }
    
    public void setYear(String year) {
        this.year = year;
    }
    
    public List<String> getFormat() {
        return format;
    }...

Activity

     private void  GetSongInfo(){


        try{


            SongsApi songsApi= SongsClient.getRetrofitClient().create(SongsApi.class);
            Call<List<Result>> call= songsApi.getSongsExampleInfo(3,randomResultPages,"pop",KEY,SECRET);

            call.enqueue(new Callback<List<Result>>() {
                @Override
                public void onResponse(Call<List<Result>> call, Response<List<Result>> response) {

                    if(response.isSuccessful()& response.body()!=null){

                        songList= new ArrayList<>(response.body());
                        RecyclerView.LayoutManager layoutManager = new LinearLayoutManager(HappySongActivity.this);
                        recyclerView.setLayoutManager(layoutManager);
                        SongAdapter= new SongAdapter(songList,SongActivity.this);
                        recyclerView.setAdapter(happySongAdapter);

                    }
                }

                @Override
                public void onFailure(Call<List<Result>> call, Throwable t) {

                    Toast.makeText(getBaseContext(), "Server Error- Couldn't load data, Please try again"+t.getMessage(), Toast.LENGTH_LONG).show();
                }
            });



        }catch (Exception ex){

            Toast.makeText(this,"Something was wrong"+ex.getMessage(),Toast.LENGTH_SHORT).show();
        }

适配器

    public class SongAdapter extends RecyclerView.Adapter<SongAdapter.CustomViewHolder> {

    private ArrayList<Result> dataList;
    private Context context;

    public SongAdapter(ArrayList<Result> dataList, Context context){

        this.dataList = dataList;
        this.context=context;
    }...

通话

      @GET("/database/search")
    Call<List<Result>> getSongsExampleInfo(@Query("per_page") Integer per_page, @Query("page") Integer page, @Query("genre") String genre, @Query("key") String key, @Query("secret") String secret);

Answer 1

您的改装服务方法具有 return 类型 Call<List<Result>> - 这意味着改装将尝试将响应解析为 json 对象列表。但是 API 是 return 单个对象，而不是列表。

检查 API 实际上 return 是什么。如果它实际上是 returning 单个 Result 对象，请将方法声明更改为：

Call<Result> getSongsExampleInfo(....

预期开始数组但在 Retrofit 调用中是开始对象

Expected begin array but was begin object in Retrofit call

java

android

retrofit