I'm working with Android Studio and I have a problem with my simple project, which uses an API. I'm trying to get images and text from TVMazeAPI http://api.tvmaze.com with the help of retrofit. The idea is in implementation of the search functionality through the SearchView. You type in some title and the app gives some results from http://api.tvmaze.com/search/shows?q=girls Images and text aren't shown and app crashes when I'm trying to make search for some show
The debugger shows this: FATAL EXCEPTION: main Process: com.kate_lebedeva.searchtheshow, PID: 3815 java.lang.NullPointerException: Attempt to invoke interface method 'int java.util.List.size()' on a null object reference at com.kate_lebedeva.searchtheshow.MovieAdapter.getItemCount(MovieAdapter.java:49)
the error is related to this lines in Adapter:
@Override
public int getItemCount() {
if(movieList != null){
return movieListFiltered.size();
} else {
return 0;
}
}
I can't handle this problem. I'm completely new in this sphere. Please give me an advice.
app gradle
dependencies {
implementation fileTree(include: ['*.jar'], dir: 'libs')
implementation 'com.android.support:appcompat-v7:28.0.0'
implementation 'com.android.support.constraint:constraint-layout:1.1.3'
testImplementation 'junit:junit:4.12'
androidTestImplementation 'com.android.support.test:runner:1.0.2'
androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
implementation 'com.android.support:design:28.0.0'
implementation 'com.android.support:cardview-v7:28.0.0'
implementation 'com.android.support:recyclerview-v7:28.0.0'
implementation 'com.squareup.retrofit2:retrofit:2.3.0'
implementation 'com.squareup.retrofit2:converter-gson:2.3.0'
implementation 'com.github.bumptech.glide:glide:4.3.1'
implementation 'com.android.support:support-v4:28.0.0'
}
android Manifest
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.kate_lebedeva.searchtheshow">
<uses-permission android:name="android.permission.INTERNET"></uses-permission>
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:roundIcon="@mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
xmlns:tools="http://schemas.android.com/tools"
tools:context=".MainActivity"
android:orientation="vertical">
<android.support.design.widget.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:theme="@style/AppTheme">
</android.support.design.widget.AppBarLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@android:color/white">
<android.support.v7.widget.RecyclerView
android:id="@+id/recyclerview"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="5dp">
</android.support.v7.widget.RecyclerView>
</LinearLayout>
</LinearLayout>
item.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_height="match_parent"
android:layout_width="wrap_content"
>
<android.support.v7.widget.CardView
android:layout_width="match_parent"
android:layout_height="160dp"
android:orientation="horizontal"
android:padding="8dp">
<ImageView
android:id="@+id/image"
android:layout_width="100dp"
android:layout_height="match_parent"
android:layout_marginRight="8dp"
android:scaleType="fitXY" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<TextView
android:id="@+id/title"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Title"
android:textSize="16sp"
android:textStyle="bold"
/>
<TextView
android:id="@+id/summary"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="4dp"
android:ellipsize="end"
android:maxLines="4"
android:text="summary"
/>
</LinearLayout>
</android.support.v7.widget.CardView>
</LinearLayout>
ApiInterface.java:
import retrofit2.Call;
import retrofit2.http.GET;
public interface ApiInterface {
@GET("search/shows?q=girls")
Call <List<Movie>> getMovies();
}
TvMazeApiClient.java
import retrofit2.Retrofit;
import retrofit2.converter.gson.GsonConverterFactory;
public class TvMazeApiClient {
public static String BASE_URL ="http://api.tvmaze.com/";
private static Retrofit retrofit;
public static Retrofit getClient(){
if(retrofit == null){
retrofit = new Retrofit.Builder()
.baseUrl(BASE_URL)
.addConverterFactory(GsonConverterFactory.create())
.build();
}
return retrofit;
}
}
Main Activity:
public class MainActivity extends AppCompatActivity {
private SearchView searchView;
private RecyclerView recyclerView;
private MovieAdapter movieAdapter;
private List<Movie> movieList;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
recyclerView = (RecyclerView) findViewById(R.id.recyclerview);
recyclerView.setLayoutManager(new LinearLayoutManager(this));
movieAdapter = new MovieAdapter();
recyclerView.setAdapter(movieAdapter);
movieList = new ArrayList<>();
ApiInterface apiService = TvMazeApiClient.getClient().create(ApiInterface.class);
Call<List<Movie>> call = apiService.getMovies();
call.enqueue(new Callback<List<Movie>>() {
@Override
public void onResponse(Call<List<Movie>> call, Response<List<Movie>> response) {
if(movieList != null) {
movieList = response.body();
Log.d("TAG", "Response = " + movieList);
movieAdapter.setMovieList(getApplicationContext(), movieList);
}
else{
Toast.makeText(MainActivity.this,"error", Toast.LENGTH_SHORT).show();
}
}
@Override
public void onFailure(Call<List<Movie>> call, Throwable t) {
Log.d("TAG","Response = "+t.toString());
Toast.makeText(MainActivity.this,t.getLocalizedMessage(), Toast.LENGTH_SHORT).show();
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.options_menu, menu);
SearchManager searchManager = (SearchManager) getSystemService(Context.SEARCH_SERVICE);
searchView = (SearchView) menu.findItem(R.id.action_search)
.getActionView();
searchView.setSearchableInfo(searchManager
.getSearchableInfo(getComponentName()));
searchView.setMaxWidth(Integer.MAX_VALUE);
searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
@Override
public boolean onQueryTextSubmit(String query) {
movieAdapter.getFilter().filter(query);
return false;
}
@Override
public boolean onQueryTextChange(String query) {
movieAdapter.getFilter().filter(query);
return false;
}
});
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if (id == R.id.action_search) {
return true;
}
return super.onOptionsItemSelected(item);
}
@Override
public void onBackPressed() {
if (!searchView.isIconified()) {
searchView.setIconified(true);
return;
}
super.onBackPressed();
}}
Adapter:
public class MovieAdapter extends RecyclerView.Adapter<MovieAdapter.MyViewHolder> implements Filterable {
private List<Movie> movieList;
private List<Movie> movieListFiltered;
private Context context;
public void setMovieList(Context context,final List<Movie> movieList){
this.context = context;
this.movieList = movieList;
this.movieListFiltered = movieList;
}
@Override
public MovieAdapter.MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.item,parent,false);
return new MyViewHolder(view);
}
@Override
public void onBindViewHolder(MovieAdapter.MyViewHolder holder, int position) {
holder.title.setText(movieListFiltered.get(position).getTitle());
Glide.with(context).load(movieList.get(position).getImageUrl()).apply(RequestOptions.centerCropTransform()).into(holder.image);
}
@Override
public int getItemCount() {
if(movieList != null){
return movieListFiltered.size();
} else {
return 0;
}
}
@Override
public Filter getFilter() {
return new Filter() {
@Override
protected FilterResults performFiltering(CharSequence charSequence) {
String charString = charSequence.toString();
if (charString.isEmpty()) {
movieListFiltered = movieList;
} else {
List<Movie> filteredList = new ArrayList<>();
for (Movie movie : movieList) {
if (movie.getTitle().toLowerCase().contains(charString.toLowerCase())) {
filteredList.add(movie);
}
}
movieListFiltered = filteredList;
}
FilterResults filterResults = new FilterResults();
filterResults.values = movieListFiltered;
return filterResults;
}
@Override
protected void publishResults(CharSequence charSequence, FilterResults filterResults) {
movieListFiltered = (ArrayList<Movie>) filterResults.values;
notifyDataSetChanged();
}
};
}
public class MyViewHolder extends RecyclerView.ViewHolder {
TextView title;
ImageView image;
public MyViewHolder(View view) {
super(view);
title = (TextView) view.findViewById(R.id.title);
image = (ImageView)view.findViewById(R.id.image);
}
}
}
Movie.java
public class Movie {
private String title;
private String imageUrl;
public Movie(String title, String imageUrl) {
this.title = title;
this.imageUrl = imageUrl;
}
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
public String getImageUrl() {
return imageUrl;
}
public void setImageUrl(String imageUrl) {
this.imageUrl = imageUrl;
}
}
