enter code here

private Intent takePictureIntent;
FirebaseDatabase database = FirebaseDatabase.getInstance();
DatabaseReference myRef;
private String pathFotoTemporal;
private static final int REQUEST_TAKE_PHOTO = 1;
private View view;
private String key;

//Expandable list Adapter
ExpandableListAdapter listAdapter;
ExpandableListView expListView;
List<String> listDataHeader;
HashMap<String, List<String>> listDataChild;

//Users
private List <User> items = new ArrayList<>();

//Obejeto a pasar
User user = new User();
String password;


//Botones
private EditText TextPass;
private EditText TextDNI;
private Button fichar;

// Adding child data
List<String> top250 = new ArrayList<String>();


@Override
public View onCreateView(LayoutInflater inflater, final ViewGroup container,
                         Bundle savedInstanceState) {
    view = inflater.inflate(R.layout.fragment_main, container, false);
    LeerFirebase();

    //Botones
    TextPass = (EditText) view.findViewById(R.id.IdpasswordUser);
    //TextDNI = (EditText) view.findViewById(R.id.DNI);

    // get the listview
    expListView = (ExpandableListView) view.findViewById(R.id.lvExp);

    // preparing list data
    prepareListData();

    listAdapter = new ExpandableListAdapter(getActivity(), listDataHeader, listDataChild);
    //expListView.setAdapter(listAdapter);

    // setting list adapter
    expListView.setAdapter(listAdapter);

    //Write in database mesage myRef.setValue("Hello, World!");

    //Llamamos al boton fichar
    fichar = (Button) view.findViewById(R.id.fichar);
    fichar.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            key = TextDNI.getText().toString();
            password = TextPass.getText().toString();
            //SuperUsuario
            if(key.equalsIgnoreCase("cesi.tic")&&password.equalsIgnoreCase("123456789")){
                ((MainActivity) getActivity()).EditarUsuario();
                fichar.setVisibility(view.INVISIBLE);
                TextPass.setVisibility(view.INVISIBLE);
                TextDNI.setVisibility(view.INVISIBLE);
            }else{
                LeerFirebase();
            }

            //Para pasar de fragment hay que comprobar el dni y el password
            /*((MainActivity) getActivity()).AbrirFichar();
            fichar.setVisibility(view.INVISIBLE);
            TextPass.setVisibility(view.INVISIBLE);*/

        }
    });
    return view;
}

private void LeerFirebase() {
    myRef = database.getReference("Usuario" +"_"+ key+"/password");
    //+"/password"
    // Read from the database
    myRef.addValueEventListener(new ValueEventListener() {
        @Override
        public void onDataChange(DataSnapshot dataSnapshot) {
            String value = dataSnapshot.getValue(String.class);
            password = TextPass.getText().toString();
            if(password.equalsIgnoreCase(value)){
                //Pasamos por pantalla
                Toast.makeText(getActivity(),"El usuario introducido es correcto",Toast.LENGTH_SHORT).show();
                //Pasamos al otro Fragment
                ((MainActivity) getActivity()).AbrirFichar(TextDNI.getText().toString());
                fichar.setVisibility(view.INVISIBLE);
                TextPass.setVisibility(view.INVISIBLE);
                TextDNI.setVisibility(view.INVISIBLE);
            }else {
                Toast.makeText(getActivity(),"El usuario introducido o la Contraseña no son correctos ",Toast.LENGTH_SHORT).show();
            }
        }

        @Override
        public void onCancelled(DatabaseError error) {
            Toast.makeText(getActivity(),"Hay un error de lectura ",Toast.LENGTH_SHORT).show();
        }
    });
}

//Al iniciarse crea el boton Visible
@Override
public void onStart() {
    final Button fichar = (Button) getView().findViewById(R.id.fichar);
    EditText getpassword = (EditText) getView().findViewById(R.id.IdpasswordUser);
    fichar.setVisibility(getView().VISIBLE);
    getpassword.setVisibility(getView().VISIBLE);
    super.onStart();
}

private File createImageFile() throws IOException {
    // Create an image file name
    String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
    String imageFileName = "JPEG_" + timeStamp + "_";
    File storageDir = Environment.getExternalStoragePublicDirectory(
            Environment.DIRECTORY_PICTURES);
    File image = File.createTempFile(
            imageFileName,  /* prefix */
            ".jpg",         /* suffix */
            storageDir      /* directory */
    );

    // Save a file: path for use with ACTION_VIEW intents
    pathFotoTemporal = "file:" + image.getAbsolutePath();
    return image;
}

private void dispatchTakePictureIntent() {
    takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
    // Ensure that there's a camera activity to handle the intent
    if (takePictureIntent.resolveActivity(getContext().getPackageManager()) != null) {
        // Create the File where the photo should go
        File photoFile = null;
        try {
            photoFile = createImageFile();
        } catch (IOException ex) {
            // Error occurred while creating the File
            ex.printStackTrace();
        }
        // Continue only if the File was successfully created
        if (photoFile != null) {
            takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT,
                    Uri.fromFile(photoFile));
            startActivityForResult(takePictureIntent, REQUEST_TAKE_PHOTO);
        }
    }
}


public void onActivityResult(int requestCode, int resultCode, Intent intent) {
    super.onActivityResult(requestCode, resultCode, intent);

    try {

        if (requestCode == REQUEST_TAKE_PHOTO) {
            if (resultCode == RESULT_OK) {
                //Glide.with(getContext()).load(pathFotoTemporal).into(imageView);
                //Falta guardar la Url en la base de datos.
            }
        }
    } catch (Exception e) {
        e.printStackTrace();

    }
}


//List Adapter
private void prepareListData() {
    listDataHeader = new ArrayList<String>();
    listDataChild = new HashMap<String, List<String>>();

    // Adding child data
    listDataHeader.add("User Name");

    //Firebase carga

    DatabaseReference ListaRef = database.getReference();

    // Read from the database
    ListaRef.addValueEventListener(new ValueEventListener() {
        @Override
        public void onDataChange(DataSnapshot dataSnapshot) {
            // This method is called once with the initial value and again
            // whenever data at this location is updated.

            items.clear();
            User usuarios;

            for( DataSnapshot i : dataSnapshot.getChildren()) {
                usuarios = i.getValue(User.class);
                items.add(usuarios);
                top250.add(" " + usuarios.getName() + " " + usuarios.getLastname());
            }
            Toast.makeText(getContext(), "Se han bajado " + items.size() + " Usuario", Toast.LENGTH_SHORT).show();
        }

        @Override
        public void onCancelled(DatabaseError error) {
            Toast.makeText(getContext(), "Error descargando las recetas", Toast.LENGTH_SHORT).show();
        }
    });
        List<String> top = new ArrayList<String>();

    for(int i = 0 ; i < top250.size(); i++){
        if (top250.get(i).isEmpty()||top250.equals(null)||top250.get(i).equals(null)||top250.get(i).equalsIgnoreCase("null null")){
            System.out.println("Noooo");
        }else{
            top.add(top250.get(i));
        }
    }
        listDataChild.put(listDataHeader.get(0), top); // Header, Child data
}