I'm working on an Android Project right now and I'm trying to parse from an URL. In my "ApiClient" I have no problem to parse. Here is my "ApiClient" class:
public class ApiClient implements Callback<Map<String, Channel>> {
static final String BASE_URL = "someURL";
public void start() {
Gson gson = new GsonBuilder()
.setLenient()
.create();
Retrofit retrofit = new Retrofit.Builder()
.baseUrl(BASE_URL)
.addConverterFactory(GsonConverterFactory.create(gson))
.build();
RestInterface restInterface = retrofit.create(RestInterface.class);
Call<Map<String, Channel>> call = restInterface.getChannels();
call.enqueue(this);
}
#Override
public void onResponse(retrofit2.Call<Map<String, Channel>> call, Response<Map<String, Channel>> response) {
System.out.println(response.code());
if(response.isSuccessful()) {
Map<String, Channel> body = response.body();
List<Channel> channels = new ArrayList<>(body.values());
}
...
}
I'm trying to get the response into a List from using callback in my "Radio" class. This the place where I'm having the problem. I tried this three too but it didn't solved my problem:
private List<Channel> listChannels = new ArrayList<Channel>();
private List<Channel> listChannels = new ArrayList<>();
private List<Channel> listChannels = new List<>();
Here is my "Radio" class:
public class Radio {
private static final String STORAGE = "radio";
private List<Channel> listChannels;
public static Radio get() {
return new Radio();
}
private SharedPreferences storage;
private Radio() {
storage = App.getInstance().getSharedPreferences(STORAGE, Context.MODE_PRIVATE);
}
public List<Channel> getData() {
RestInterface restInterface = SingletonClass.getService();
restInterface.getChannels().enqueue(new Callback<Map<String, Channel>>() {
#Override
public void onResponse(Call<Map<String, Channel>> call, Response<Map<String, Channel>> response) {
if(response.isSuccessful()){
Map<String, Channel> body = response.body();
List<Channel> channels = new ArrayList<>(body.values());
loadChannels(channels);
}
}
#Override
public void onFailure(Call<Map<String, Channel>> call, Throwable t) {
}
});
System.out.println(listChannels.get(1).getArtist());
return listChannels;
}
public boolean isRated(int itemId) {
return storage.getBoolean(String.valueOf(itemId), false);
}
public void setRated(int itemId, boolean isRated) {
storage.edit().putBoolean(String.valueOf(itemId), isRated).apply();
}
private void loadChannels(List<Channel> channels){
listChannels.clear();
listChannels.addAll(channels);
}
}
Here is my interface class:
public interface RestInterface {
#GET("someURL")
retrofit2.Call<Map<String, Channel>> getChannels();
}
and my SingletonClass:
public class SingletonClass{
private static final Retrofit RETROFIT = new Retrofit.Builder()
.baseUrl(someURL)
.addConverterFactory(GsonConverterFactory.create())
.build();
private static final RestInterface SERVICE = RETROFIT.create(RestInterface.class);
public static RestInterface getService(){
return SERVICE;
}
}
I don't know what should I do to fill the List in my Radio class now. I'm totally open to suggestions. Thanks for the help.
Are you getting an empty list? You're asynchronously setting in the channel data in getData(), so if you're trying to get the data by reading it in the next line, it may not be loaded yet.
This means that when you call System.out.println(listChannels.get(1).getArtist()), you won't see the result of loadChannels, because that call happens right after you call enqueue() while loadChannels() is running on a separate thread. If you moved that into onResponse() you might have more luck.
In Android, a fairly easy way to do things like this and interact with the UI is by using AsyncTask, which for you would look something like this:
private class loadChannelTask extends AsyncTask<Void, Void, List<Channel>> {
protected List<Channel> doInBackground() {
//get response
//pass to load channels
}
protected void onPostExecute() {
System.out.println(listChannels.get(1).getArtist()); //presumably the artist name
}
}
Related
I've seen a few similar questions but they don't seem to answer my problem exactly. I'm pulling a list with Retrofit and I want to export it to a list and create a listview. But I am not getting any return from onResponse. I've also tried returning a list directly with return. Please help.
this is the callback func
listCatcher just holds a list
Ibreeds is interface
public ListCatcher allBreeds(View view){
ArrayList<String> breedList = new ArrayList<>(breeds);
Ibreeds.allBreeds().enqueue(new Callback<Breeds>() {
#Override
public void onResponse(Call<Breeds> call, Response<Breeds> response) {
List<String> breeds = response.body().getMessage();
for (String b: breeds){
breedList.add(b);
}
}
#Override
public void onFailure(Call<Breeds> call, Throwable t) {
Snackbar.make(view,R.string.connectionStatus, 3000 ).show();
}
});
ListCatcher listcatcher = new ListCatcher(breedList);
return listcatcher;
}
public interface BreedsDAOInterface {
#GET("breeds/list")
Call<Breeds> allBreeds();
#GET("breed/{breed}/list")
Call<Breeds> listSubBreed(#Path("breed") String breed);
#GET("breed/{breed}/images")
Call<Breeds> listBreedImages(#Path("breed") String breed);
#GET("breed/{breed}/{subBreed}/images")
Call<Breeds> listSubBreedImages(#Path("breed") String breed, #Path("subBreed") String subBreed);
#GET("breeds/image/random")
Call<Breeds> iFeelLucky();
}
public class ApiUtils {
public static final String BASE_URL = "https://dog.ceo/api/";
public static BreedsDAOInterface getBreedsDaoInterface(){
return RetrofitClient.getClient(BASE_URL).create(BreedsDAOInterface.class);
}
}
public class RetrofitClient {
private static Retrofit retrofit = null;
public static Retrofit getClient(String baseURL){
if (retrofit == null){
retrofit = new Retrofit
.Builder()
.baseUrl(baseURL)
.addConverterFactory(GsonConverterFactory.create())
.build();
}
return retrofit;
}
}
public class Breeds {
#SerializedName("message")
#Expose
private List<String> message;
public List<String> getMessage() {
return message;
}
public void setMessage(List<String> message) {
this.message = message;
}
}
EDIT
I found the solution to the problem:
listCatcher deleted
public class HomeActivity extends AppCompatActivity {
List<String> breedsList = new ArrayList<>();
private BreedsInterface Ibreeds;
private RecyclerViewAdapter RWAdapter;
private ActivityHomeBinding binding;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
binding = ActivityHomeBinding.inflate(getLayoutInflater());
setContentView(binding.getRoot());
Ibreeds = ApiUtils.getBreedsDaoInterface();
allBreeds();
}
public void allBreeds(){
Ibreeds.allBreeds().enqueue(new Callback<Answer>() {
#Override
public void onResponse(Call<Answer> call, Response<Answer> response) {
List<String> breedResponceList = response.body().getMessage();
breedsList.clear();
breedsList.addAll(breedResponceList);
initRecyclerView();
}
#Override
public void onFailure(Call<Answer> call, Throwable t) {
throwError();
}
});
}
private void throwError() {
Snackbar.make(binding.getRoot(), R.string.connectionStatus, 3000).show();
}
private void initRecyclerView() {
RWAdapter = new RecyclerViewAdapter(breedsList);
binding.recyclerView.setLayoutManager(new LinearLayoutManager(this));
binding.recyclerView.setAdapter(RWAdapter);
}
}
I added the adapter to the enqueue function via a function
I am implementing android pagination library in my app and would like to pass "id" of an item from my activity to the data source where my network call is made
AddCommentActivity.java
//I want to pass this string to the network call.
String image_id = getIntent().getStringExtra("image_id");
CommentViewModel commentViewModel = new ViewModelProvider(this).get(CommentViewModel.class);
CommentDataSource.java
public class CommentDataSource extends PageKeyedDataSource<Long, Comment> {
public CommentDataSource(){
progress_bar = new MutableLiveData<>();
}
#Override
public void loadInitial(#NonNull final LoadInitialParams<Long> params, #NonNull final LoadInitialCallback<Long, Comment> callback) {
RestApi restApi = RetrofitApi.create();
Call<CommentResponse> call = restApi.getComments(FIRST_PAGE, "I want the image_id from activity here");
call.enqueue(new Callback<CommentResponse>() {
#Override
public void onResponse(Call<CommentResponse> call, Response<CommentResponse> response) {
}
CommentDataSourceFactory.java
public class CommentDataFactory extends DataSource.Factory<Long, Comment> {
public MutableLiveData<CommentDataSource> commentLiveDataSource = new MutableLiveData<>();
public CommentDataFactory() {
}
#Override
public DataSource<Long, Comment> create() {
CommentDataSource commentDataSource = new CommentDataSource();
commentLiveDataSource.postValue(commentDataSource);
return commentDataSource;
}
CommentViewModel.java
public class CommentViewModel extends ViewModel {
public LiveData<PagedList<Comment>> commentPagedList;
public LiveData<CommentDataSource> liveDataSource;
public LiveData progressBar;
public CommentViewModel(){
CommentDataFactory commentDataFactory = new CommentDataFactory();
liveDataSource = commentDataFactory.commentLiveDataSource;
progressBar = Transformations.switchMap(liveDataSource, CommentDataSource::getProgressBar);
PagedList.Config config = new PagedList.Config.Builder()
.setEnablePlaceholders(false)
.setPageSize(CommentDataSource.PAGE_SIZE)
.build();
commentPagedList = new LivePagedListBuilder<>(commentDataFactory, config).build();
}
public LiveData<PagedList<Comment>> getCommentData(){
return commentPagedList;
}
public void getRefreshedData(){
getCommentData().getValue().getDataSource().invalidate();
}
}
How to do that.? I checked Passing variable to paging library class which is exactly what I want to do but I dont understand it and the code gives errors. Errors such as
Cannot create an instance of class CommentViewModel
CommentViewModel has no zero argument constructor
Okay do:
commentViewmodel1.getCommentData().observe(this, new Observer<PagedList<Comments>>(){
#Override
public void onChanged(PagedList<Comment>
comments){
adapter.submitList(comments);
}
});
Android newly here. I am working on a popular movies app that fetches some movie data from moved.org and display to users when tapping on movie thumbnail. Recently, I have been working on setting up retrofit in my app for two weeks. I am trying to use MVVM pattern. My goals is to get response from api.moviedb.org so that, eventually, I can display movie posters in recycler view. For some reason, I am not able to get any response from the api call using retrofit. I think I did something wrong with setting up retrofit but can't find out how I messed up... I feel like I am hard stuck.. Any help from experienced android developers would be much appreciated:)
Github link to my project
On create method in MainActivity:
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mRecyclerView = findViewById(R.id.rvMovies);
movieViewModel = ViewModelProviders.of(this).get(MovieViewModel.class);
// Log.d("viewmodel", String.valueOf(movieViewModel));
movieViewModel.getMoviesLiveData().observe(this, new Observer<MovieResult>() {
#Override
public void onChanged(MovieResult movieResult) {
Log.d("movieResult", String.valueOf(movieResult));
}
});
}
ViewModel Class:
public class MovieViewModel extends AndroidViewModel {
private MutableLiveData<MovieResult> movieLiveData;
private MovieRepository movieRepository;
public MovieViewModel(#NonNull Application application){
super(application);
}
public void init(){
if (movieLiveData != null){
return;
}
movieRepository = MovieRepository.getInstance();
movieLiveData = movieRepository.getMovies("api_key_here");
}
public LiveData<MovieResult> getMoviesLiveData() {
init();
return movieLiveData;
}
}
Respository:
public class MovieRepository {
private static MovieRepository movieRepository;
public static MovieRepository getInstance(){
if (movieRepository == null){
movieRepository = new MovieRepository();
}
return movieRepository;
}
private GetMovieService service;
public MovieRepository(){
service = RetrofitInstance.getRetrofitInstance().create(GetMovieService.class);
}
public MutableLiveData<MovieResult> getMovies(String api){
Log.d("getmovies","called");
final MutableLiveData<MovieResult> movieData = new MutableLiveData<>();
service.getMovieResult(api).enqueue(new Callback<MovieResult>() {
#Override
public void onResponse(Call<MovieResult> call, Response<MovieResult> response) {
if (response.isSuccessful()){
movieData.setValue(response.body());
Log.d("debug", String.valueOf(movieData));
}
}
#Override
public void onFailure(Call<MovieResult> call, Throwable t) {
movieData.setValue(null);
Log.d("onfailure","why");
}
});
return movieData;
}
}
RetrofitInstance:
public class RetrofitInstance {
private static Retrofit retrofit;
private static final String BASE_URL = "http://api.themoviedb.org/3/";
public static Retrofit getRetrofitInstance(){
if(retrofit == null){
retrofit = new retrofit2.Retrofit.Builder()
.baseUrl(BASE_URL)
.addConverterFactory(GsonConverterFactory.create())
.build();
}
return retrofit;
}
}
GetMovieService.Java
public interface GetMovieService {
#GET("movie/popular")
Call<MovieResult> getMovieResult(#Query("api_key") String apiKey);
}
logical:
log output
I am using from rx for connect to service with retrofit, bellow is RetrofitApi.java :
public class RetrofitApi {
private static PublicApi retrofit = null;
public static PublicApi getClient(String url) {
retrofit = new Retrofit.Builder()
.baseUrl(url)
.addCallAdapterFactory(RxJava2CallAdapterFactory.create())
.addConverterFactory(GsonConverterFactory.create())
.build().create(PublicApi.class);
return retrofit;
}
}
And here is PublicApi.java :
public interface PublicApi {
#GET("/web_service/mobile/rest")
Observable<LastNews> lastNews(#Query("function") String function);
}
Bellow I am connecting to my service :
#Override
public void fetchLastNewsStartPage(RemoteDataSource.ResultListener<List<LastNews>> resultListener) {
PublicApi publicApi = RetrofitApi.getClient("https://xxx.xxx.xxx/web_service/");
CompositeDisposable mCompositeDisposable = new CompositeDisposable();
mCompositeDisposable.add(publicApi.lastNews("getLastNews")
.observeOn(AndroidSchedulers.mainThread())
.subscribeOn(Schedulers.io())
.subscribe(this::handleResponse, this::handleError));
}
My problem is here, how can I send parameter to handleResponse and handleError. I need to send this RemoteDataSource.ResultListener<List<LastNews>> resultListener to handleResponse and handleError:
private void handleResponse(LastNews lastNewses) {
}
private void handleError(Throwable error) {
}
Just don't use method reference as it can only accept one parameter. You can achieve the result with a lambda expression. Instead of
this::handleResponse
write
lastNews -> handleResponse(lastNews, resultListener)
I'm new to retrofit and i am trying te get a json response to an object called RootObject. The error that i am stuck with is :
"Error:(21, 44) error: incompatible types: NewsController cannot be
converted to Callback>"
Does someone now my mistake here? thanks in regards!
public class NewsController {
public void getNews(){
Retrofit retrofit = new Retrofit.Builder().baseUrl("apilink").addConverterFactory(GsonConverterFactory.create()).build();
GetNewsService service = retrofit.create(GetNewsService.class);
try {
service.GetNewsItems().enqueue(this); //asynchronous
Response<List<RootObject>> response = service.GetNewsItems().execute(); //synchronous
}
catch (IOException e){
}
}
}
class to put the data:
public class RootObject implements Serializable {
public ArrayList<Result> results ;
public int nextId;
public ArrayList<Result> getResults() { return results; }
public int getNextId() { return nextId; }
public String toString() {
return String.format("JEEJ" + nextId);
}
}
Interface:
public interface GetNewsService {
#GET("/Articles")
Call<List<RootObject>> GetNewsItems();
}
First of all,
change your interface to this:
public interface GetNewsService {
#GET("/Articles")
void GetNewsItems(Callback<List<RootObject>> cb);
}
Also change your newsController class.
public class NewsController {
private RestAdapter restAdapter;
static final String API_URL = "[Enter your API base url here]";
public void getNews(){
OkHttpClient mOkHttpClient = new OkHttpClient();
mOkHttpClient.setConnectTimeout(15000,TimeUnit.MILLISECONDS);
mOkHttpClient.setReadTimeout(15000,TimeUnit.MILLISECONDS);
restAdapter = new RestAdapter.Builder().setEndpoint(API_URL).setClient(new OkClient(mOkHttpClient)).setLogLevel(RestAdapter.LogLevel.FULL) .build();
GetNewsService service = restAdapter.create(GetNewsService.class);
Callback<List<RootObject> cb = new Callback<List<RootObject>>() {
#Override
public void success(List<RootObject> rootObjectList, Response response) {
//whatever you want to do with the fetched news items
}
#Override
public void failure(RetrofitError error) {
//whatever you want to do with the error
}
};
service.GetNewsItems(cb);
}
}
You'll need to add the following dependencies in your build.gradle:
compile 'com.squareup.retrofit:retrofit:1.9.0'
compile 'com.google.code.gson:gson:2.3.1'
compile 'com.squareup.okhttp:okhttp:2.4.0'
#megh vidani's answer works, but he had you switch your code from Retrofit 2 to Retrofit 1. Here is how to do it in Retrofit 2. You would need to go back to your original gradle settings, etc. --
public class NewsController {
public void getNews(){
Retrofit retrofit = new Retrofit.Builder().baseUrl("apilink").addConverterFactory(GsonConverterFactory.create()).build();
GetNewsService service = retrofit.create(GetNewsService.class);
service.GetNewsItems().enqueue(new Callback<List<RootObject>>() {
#Override
public void onResponse(Response<List<RootObject>> response) {
// Handle your response
// Note HTTP errors are delivered here, you can check
// response.isSuccess() or response.code() to determine
// HTTP failures
}
#Override
public void onFailure(Throwable t) {
// Network errors
}
});
}
}