【发布时间】：2017-10-24 05:14:24
【问题描述】：
我正在使用 RetroFit 创建一个应用程序。我从 URL 获取 JSON 字符串中的数据，并使用 RetroFit 将其填充到回收视图中。
我的问题
我的问题是，当应用程序执行时，它显示以下错误：：
E/RecyclerView：没有附加适配器；跳过布局
E/RecyclerView: 未连接适配器；跳过布局
D/错误： java.lang.IllegalStateException：应为 BEGIN_OBJECT，但为 BEGIN_ARRAY 在第 1 行第 2 列路径 $
我的支票
- 检查网址
- 使用浏览器检查 URL.. 成功返回 json
我努力解决这个问题，但没有解决方案。
我手动运行了json url，成功返回了json数据。但是在程序上，它返回错误。
JSON 数据样本
[
{
"user_id": "59e4897140d1666c6e8b4567",
"post_id": "59eeb10d40d16686168b4567",
"post_url": "http://demo.cogzideltemplates.com/anan/posts/images/22f3fb0b974be4968118a410e0ad48f7.jpg",
"post_type": "image",
"caption": "vvnnk",
"created": 1508815117,
"time_diff": "1 hours ago",
"first_name": null,
"last_name": null,
"user_name": null,
"email": null,
"profile_pic": "http://demo.cogzideltemplates.com/anan/images/users/no_avatar.jpg",
"category": "New release"
},
{
"user_id": "59e4897140d1666c6e8b4567",
"post_id": "59ee306940d166697f8b4567",
"post_url": "http://demo.cogzideltemplates.com/anan/posts/images/8f81bd77e60e596cf458d42a743897f8.jpg",
"post_type": "image",
"caption": "cutyy",
"created": 1508782185,
"time_diff": "10 hours ago",
"first_name": null,
"last_name": null,
"user_name": null,
"email": null,
"profile_pic": "http://demo.cogzideltemplates.com/anan/images/users/no_avatar.jpg",
"category": "Super Star"
}
]
Post.java（JSON 的 POJO）
import com.google.gson.annotations.Expose;
import com.google.gson.annotations.SerializedName;
public class Post {
@SerializedName("user_id")
@Expose
private String userId;
@SerializedName("post_id")
@Expose
private String postId;
@SerializedName("post_url")
@Expose
private String postUrl;
@SerializedName("post_type")
@Expose
private String postType;
@SerializedName("caption")
@Expose
private String caption;
@SerializedName("created")
@Expose
private Integer created;
@SerializedName("time_diff")
@Expose
private String timeDiff;
@SerializedName("first_name")
@Expose
private Object firstName;
@SerializedName("last_name")
@Expose
private Object lastName;
@SerializedName("user_name")
@Expose
private Object userName;
@SerializedName("email")
@Expose
private Object email;
@SerializedName("profile_pic")
@Expose
private String profilePic;
@SerializedName("category")
@Expose
private String category;
public String getUserId() {
return userId;
}
public void setUserId(String userId) {
this.userId = userId;
}
public String getPostId() {
return postId;
}
public void setPostId(String postId) {
this.postId = postId;
}
public String getPostUrl() {
return postUrl;
}
public void setPostUrl(String postUrl) {
this.postUrl = postUrl;
}
public String getPostType() {
return postType;
}
public void setPostType(String postType) {
this.postType = postType;
}
public String getCaption() {
return caption;
}
public void setCaption(String caption) {
this.caption = caption;
}
public Integer getCreated() {
return created;
}
public void setCreated(Integer created) {
this.created = created;
}
public String getTimeDiff() {
return timeDiff;
}
public void setTimeDiff(String timeDiff) {
this.timeDiff = timeDiff;
}
public Object getFirstName() {
return firstName;
}
public void setFirstName(Object firstName) {
this.firstName = firstName;
}
public Object getLastName() {
return lastName;
}
public void setLastName(Object lastName) {
this.lastName = lastName;
}
public Object getUserName() {
return userName;
}
public void setUserName(Object userName) {
this.userName = userName;
}
public Object getEmail() {
return email;
}
public void setEmail(Object email) {
this.email = email;
}
public String getProfilePic() {
return profilePic;
}
public void setProfilePic(String profilePic) {
this.profilePic = profilePic;
}
public String getCategory() {
return category;
}
public void setCategory(String category) {
this.category = category;
}
}
DataAdapter.java
public class DataAdapter extends RecyclerView.Adapter<DataAdapter.ViewHolder> {
private ArrayList<Post> post;
public DataAdapter(ArrayList<Post> post) {
this.post = post;
}
@Override
public DataAdapter.ViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
View view = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.card_row, viewGroup, false);
return new ViewHolder(view);
}
@Override
public void onBindViewHolder(DataAdapter.ViewHolder viewHolder, int i) {
viewHolder.tv_userId.setText(post.get(i).getUserId());
viewHolder.tv_postId.setText(post.get(i).getPostId());
viewHolder.tv_postType.setText(post.get(i).getPostType());
viewHolder.tv_caption.setText(post.get(i).getCaption());
Picasso.with(viewHolder.tv_postUrl.getContext()).load(post.get(i).getPostUrl()).into(viewHolder.tv_postUrl);
Picasso.with(viewHolder.tv_profilePic.getContext()).load(post.get(i).getProfilePic()).into(viewHolder.tv_profilePic);
viewHolder.tv_timeDiff.setText(post.get(i).getTimeDiff());
viewHolder.tv_category.setText(post.get(i).getCategory());
viewHolder.tv_created.setText(post.get(i).getCreated());
}
@Override
public int getItemCount() {
return post.size();
}
public class ViewHolder extends RecyclerView.ViewHolder{
private TextView tv_userId,tv_postId,tv_postType,tv_caption,tv_timeDiff,tv_category,tv_created;
ImageView tv_profilePic,tv_postUrl;
public ViewHolder(View view) {
super(view);
tv_userId = (TextView)view.findViewById(R.id.tv_userId);
tv_postUrl = (ImageView) view.findViewById(R.id.tv_postUrl);
tv_postType = (TextView)view.findViewById(R.id.tv_postType);
tv_caption = (TextView)view.findViewById(R.id.tv_caption);
tv_postId = (TextView)view.findViewById(R.id.tv_postId);
tv_timeDiff = (TextView)view.findViewById(R.id.tv_timeDiff);
tv_profilePic = (ImageView)view.findViewById(R.id.tv_profilePic);
tv_category = (TextView)view.findViewById(R.id.tv_category);
tv_created = (TextView)view.findViewById(R.id.tv_created);
}
}
}
JSONResponse.java
public class JSONResponse {
private Post[] post;
public Post[] getPost() {
return post;
}
}
RequestInterface.java
import retrofit2.Call;
import retrofit2.http.GET;
public interface RequestInterface {
@GET("anan/mobile/posts/viewall_Posts")
Call<JSONResponse> getJSON();
}
MainActivity.java
public class MainActivity extends AppCompatActivity {
private RecyclerView recyclerView;
private ArrayList<Post> data;
private DataAdapter adapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initViews();
}
private void initViews(){
recyclerView = (RecyclerView)findViewById(R.id.card_recycler_view);
recyclerView.setHasFixedSize(true);
RecyclerView.LayoutManager layoutManager = new LinearLayoutManager(getApplicationContext());
recyclerView.setLayoutManager(layoutManager);
loadJSON();
}
private void loadJSON(){
Retrofit retrofit = new Retrofit.Builder()
.baseUrl("http://demo.cogzideltemplates.com")
.addConverterFactory(GsonConverterFactory.create())
.build();
RequestInterface request = retrofit.create(RequestInterface.class);
Call<JSONResponse> call = request.getJSON();
System.out.println("enter the url: "+call.request().url());
call.enqueue(new Callback<JSONResponse>() {
@Override
public void onResponse(Call<JSONResponse> call, Response<JSONResponse> response) {
JSONResponse jsonResponse = response.body();
data = new ArrayList<>(Arrays.asList(jsonResponse.getPost()));
adapter = new DataAdapter(data);
recyclerView.setAdapter(adapter);
}
@Override
public void onFailure(Call<JSONResponse> call, Throwable t) {
Log.d("Error",t.getMessage());
}
});
}
}
这些是我的课。请帮我解决这个问题。
【问题讨论】：
-
JSONResponse 是对象，你 api 返回的 JSONArray 不是 JSONObject
-
您没有在布局管理器中指定它是垂直、水平、网格等
-
@JRamesh 请解释一下
-
@RageshDAntony 如果您想使用上面的代码解析响应，那么响应将是这样的 {[{},{}]}
标签： java android json android-recyclerview retrofit