I'm trying to show a Snack bar in a fragment but it gives me the following error:
Attempt to invoke virtual method 'android.view.View android.app.Activity.findViewById (int) 'on a null object reference
This error happens when I want to show my Snack bar through a button, I do not understand why the error happens, this is my Snack bar code:
public void desplegar() {
Snackbar snackbar = Snackbar.make(getActivity().findViewById(android.R.id.content),
"Se ha añadido a tus favoritos", Snackbar.LENGTH_LONG).setAction(getString(R.string.verfav), new View.OnClickListener() {
@Override
public void onClick(View view) {
FragmentTransaction transaction = getFragmentManager().beginTransaction();
transaction.replace(R.id.qwe, new Favoritos());
transaction.commit();
}
});
//ACTION
snackbar.setActionTextColor(getResources().getColor(R.color.textoblanco));
View snackBarView = snackbar.getView();
//BACKGROUND
snackBarView.setBackgroundColor(getResources().getColor(R.color.toolbar));
//MESSAGE
TextView mensaje = (TextView) snackBarView.findViewById(android.support.design.R.id.snackbar_text);
mensaje.setTextColor(getResources().getColor(R.color.textoblanco));
snackbar.show();
}
I already tried different ways but they did not work for me, I do not know why that error is shown, this is my complete code:
public class Inicio extends Fragment implements noticiasAdapter.OnEventMovieListener, Response.Listener<JSONObject>, Response.ErrorListener{
RecyclerView recyclerView;
private List<Noticias> noticias;
private noticiasAdapter noticiasadapter;
public static final String TAG = Noticias.class.getName();
RequestQueue request;
JsonObjectRequest jsonObjectRequest;
Context context;
public Inicio(){
}
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState){
View view = inflater.inflate(R.layout.inicio, container, false);
recyclerView = (RecyclerView)view.findViewById(R.id.recycler_view);
noticias = new ArrayList<>();
noticiasadapter = new noticiasAdapter(noticias);
noticiasadapter.setOnEventMovieListener(this);
RecyclerView.LayoutManager layoutManager = new LinearLayoutManager(getContext());
recyclerView.setLayoutManager(layoutManager);
request = Volley.newRequestQueue(getActivity());
cargarWebService();
return view;
}
private void cargarWebService() {
String url = "http://192.168.1.72:80/webservicemgrex/listaNoticias.php";
jsonObjectRequest = new JsonObjectRequest(Request.Method.GET,url,null,this,this);
request.add(jsonObjectRequest);
}
@Override
public void onResponse(JSONObject response) {
Noticias news = null;
JSONArray json = response.optJSONArray("inicio");
try{
for (int i=0; i<json.length(); i++){
news = new Noticias();
JSONObject jsonObject = null;
jsonObject = json.getJSONObject(i);
news.setIdNoticia(jsonObject.optInt("idNoticia"));
news.setTituloNoticia(jsonObject.optString("tituloNoticia"));
news.setSubtituloNoticia(jsonObject.getString("subtituloNoticia"));
news.setImagenNoticia(jsonObject.getString("imagenNoticia"));
news.setDescripcionNoticia(jsonObject.getString("descripcionNoticia"));
noticias.add(news);
}
noticiasAdapter adapter = new noticiasAdapter(noticias);
recyclerView.setAdapter(adapter);
noticiasadapter.notifyDataSetChanged();
}catch (JSONException e){
Toast.makeText(getActivity(),"Error al cargar la informacion del servidor: "+e, Toast.LENGTH_LONG).show();
e.printStackTrace();
}
}
@Override
public void onErrorResponse(VolleyError error) {
Toast.makeText(getActivity(),"No se pudo consultar los registros: "+error.toString(), Toast.LENGTH_LONG).show();
Log.i("Error","No se pudo consultar el registro: "+error.toString());
}
@Override
public void onStop() {
super.onStop();
}
@Override
public void onResume() {
super.onResume();
}
@Override
public void onPause() {
super.onPause();
}
@Override
public void onDestroy() {
super.onDestroy();
}
//Revisar este bloque
@Override
public void vistaDetalle(String tituloNoticia, String subtituloNoticia, String imagenNoticia, String descripcionNoticia) {
Intent intent = new Intent(getActivity(), DescripcionNoticias.class);
intent.putExtra("titulon",tituloNoticia);
intent.putExtra("descripcionn", descripcionNoticia);
intent.putExtra("imagen", imagenNoticia);
startActivity(intent);
getActivity().overridePendingTransition(R.anim.left_in, R.anim.left_out);
}
public void desplegar() {
Snackbar snackbar = Snackbar.make(getActivity().findViewById(android.R.id.content),
"Se ha añadido a tus favoritos", Snackbar.LENGTH_LONG).setAction(getString(R.string.verfav), new View.OnClickListener() {
@Override
public void onClick(View view) {
FragmentTransaction transaction = getFragmentManager().beginTransaction();
transaction.replace(R.id.qwe, new Favoritos());
transaction.commit();
}
});
//ACTION
snackbar.setActionTextColor(getResources().getColor(R.color.textoblanco));
View snackBarView = snackbar.getView();
//BACKGROUND
snackBarView.setBackgroundColor(getResources().getColor(R.color.toolbar));
//MESSAGE
TextView mensaje = (TextView) snackBarView.findViewById(android.support.design.R.id.snackbar_text);
mensaje.setTextColor(getResources().getColor(R.color.textoblanco));
snackbar.show();
}
}
This is the XML that is loaded in that fragment:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:id="@+id/content"
android:layout_height="match_parent"
app:layout_behavior="@string/appbar_scrolling_view_behavior"
tools:context="com.example.enriq.seccion15update.Principal"
tools:showIn="@layout/app_bar_main">
<android.support.v7.widget.RecyclerView
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/recycler_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_marginTop="60dp"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_alignParentTop="true"
tools:context=".Principal">
</android.support.v7.widget.RecyclerView>
</RelativeLayout>
and this is my cardview that I post to show the content:
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:paddingEnd="16dp"
android:paddingStart="16dp"
android:paddingTop="16dp">
<TextView
android:id="@+id/tituloNoticia"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:textColor="#000000"
android:text="@string/tituloNoticia"
android:fontFamily="sans-serif"
android:textStyle="bold"
android:layout_marginBottom="5dp"
android:textSize="18sp" tools:targetApi="jelly_bean"/>
<TextView
android:id="@+id/subtituloNoticia"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:textColor="#000000"
android:layout_marginBottom="5dp"
android:text="@string/subitutloNoticias"
android:textSize="15sp"
android:fontFamily="sans-serif" tools:targetApi="jelly_bean"/>
<ImageView
android:id="@+id/imagenNotica"
android:layout_width="match_parent"
android:layout_height="200dp"
android:contentDescription="@string/linea_divisora_de_texto_y_video"
android:scaleType="fitCenter"
app:srcCompat="@drawable/example" />
<android.support.design.widget.FloatingActionButton
android:id="@+id/floatingActionButton"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="right"
android:layout_marginRight="10dp"
android:layout_marginBottom="10dp"
android:clickable="true"
android:tint="@color/barraestatus"
app:backgroundTint="@color/textoblanco"
app:elevation="5dp"
app:rippleColor="@color/barraestatus"
app:srcCompat="@drawable/unliked" />
<TextView
android:id="@+id/descripcionNoticias"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="20dp"
android:text="Descripcion"
android:maxLines="3"
android:textAppearance="@style/TextAppearance.AppCompat.Light.Widget.PopupMenu.Small"
android:textSize="14sp" />
<Button
android:id="@+id/showMore"
style="@android:style/Widget.Material.Button.Borderless"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="5dp"
android:shadowColor="@color/barraestatus"
android:text="Ver nota completa"
android:textColor="@color/barraestatus"
android:textStyle="bold"
android:tint="@color/barraestatus"
app:backgroundTint="@color/textoblanco" tools:targetApi="lollipop"/>
</LinearLayout>
The deploy method I send to call from this class called noticiasWebService, is just a class that you create to be able to run another webService:
public class noticiasWebService extends AppCompatActivity implements Response.Listener<JSONObject>, Response.ErrorListener {
RequestQueue request;
JsonObjectRequest jsonObjectRequest;
private Context context;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
context = getApplicationContext();
}
public void update(String tituloNoticia, String subtituloNoticia, String imagenNoticia, String descripcionNoticia, Context context) {
String url = "http://192.168.1.72:80/webservicemgrex/agregarFavoritos.php?tituloFavorito="+tituloNoticia+"" +
"&subtituloFavorito="+subtituloNoticia+
"&imagenFavorito="+imagenNoticia+
"&descripcionFavoritos="+descripcionNoticia;
url = url.replace(" ","%20");
request = Volley.newRequestQueue(context);
jsonObjectRequest = new JsonObjectRequest(Request.Method.GET,url,null,this,this);
request.add(jsonObjectRequest);
Inicio inicio = new Inicio();
inicio.desplegar();
}
@Override
public void onResponse(JSONObject response) {
Log.i("Error","Se haregistrado con exito: "+response);
}
@Override
public void onErrorResponse(VolleyError error) {
Log.i("Error","No se pudo consultar el registro: "+error.toString());
}
}