I have this problem when i open the view of "Eventos", im trying to delete from de database the selected items from the listview.
public class ShowData extends AppCompatActivity {
DatabaseReference databaseReference;
ListView listView;
ArrayList<String> arrayList = new ArrayList<>();
ArrayAdapter<String> arrayAdapter;
Button btnDelete;
Module module;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_show_data);
databaseReference = FirebaseDatabase.getInstance().getReference("Eventos");
listView = (ListView) findViewById(R.id.listViewShow);
btnDelete = (Button) findViewById(R.id.btnBorrarElemento);
module=((Module)getApplication());
arrayAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, arrayList);
listView.setAdapter(arrayAdapter); .....
... listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> paramAdapterView, View view, int position, long id) {
module.setGvalue_titulo(arrayList.get(position));
module.setGvalue_descripcion(arrayList.get(position));
module.setGvalue_fecha(arrayList.get(position));
module.setGvalue_url(arrayList.get(position));
}
});
btnDelete.setOnClickListener(new View.OnClickListener(){
@Override
public void onClick(View v){
final String str = module.getGvalue_titulo().substring(0, 6);
if(str == ""){
Toast.makeText(ShowData.this, "No se ha seleccionado ningun elemento para eliminar", Toast.LENGTH_SHORT).show();
}
else {
databaseReference.child("Eventos").child(str).addListenerForSingleValueEvent(new ValueEventListener() {
@Override
public void onDataChange(@NonNull DataSnapshot dataSnapshot) {
databaseReference.child(str).removeValue();
}
@Override
public void onCancelled(@NonNull DatabaseError databaseError) {
}
});
Toast.makeText(ShowData.this, "Evento Eliminado", Toast.LENGTH_SHORT).show();
Intent intent = new Intent(getApplicationContext(),ShowData.class);
startActivity(intent);
}
}
}); ....
The module has the getters and setters necessaries:
In my manifest, I have this:
