将列表添加到Cloud Firebase - Android _Firebase

一箫一剑平生意，负尽狂名十五年。这篇文章主要讲述将列表添加到Cloud Firebase - Android相关的知识，希望能为你提供帮助。
我根据Youtube的优秀导游做了一切。 https://www.youtube.com/watch?v=W-L6Cr2WP18- 我推荐。不幸的是，我使用片段而不是活动，但我有一个错误。
主要内容：

public class MainActivity extends AppCompatActivity implements NavigationView.OnNavigationItemSelectedListener{private String userEmail, userName; private GoogleApiClient googleApiClient; private FirebaseAuth firebaseAuth; private FirebaseFirestore rootRef; private FirebaseAuth.AuthStateListener authStateListener; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main_activity); GoogleSignInAccount googleSignInAccount = GoogleSignIn.getLastSignedInAccount(this); if(googleSignInAccount != null){ String userEmail = googleSignInAccount.getEmail(); String userName = googleSignInAccount.getDisplayName(); Toast.makeText(this, "Witaj " + userName, Toast.LENGTH_LONG).show(); }GoogleApiClient googleApiClient = new GoogleApiClient.Builder(this) .addApi(Auth.GOOGLE_SIGN_IN_API) .build(); firebaseAuth = FirebaseAuth.getInstance(); rootRef = FirebaseFirestore.getInstance(); authStateListener = new FirebaseAuth.AuthStateListener() { @Override public void onAuthStateChanged(@NonNull FirebaseAuth firebaseAuth) { FirebaseUser firebaseUser = firebaseAuth.getCurrentUser(); if(firebaseUser == null){ Intent intent = new Intent(MainActivity.this, LoginActivity.class); startActivity(intent); } } }; Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar); setSupportActionBar(toolbar); DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout); ActionBarDrawerToggle toggle = new ActionBarDrawerToggle( this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close); drawer.setDrawerListener(toggle); toggle.syncState(); NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view); navigationView.setNavigationItemSelectedListener(this); //add this line to display menu1 when the activity is loaded displaySelectedScreen(R.id.nav_menu1); }private void signOut(){ Map< String, Object> map = new HashMap< > (); map.put("tokenId", FieldValue.delete()); rootRef.collection("users").document(userEmail).update(map).addOnSuccessListener(new OnSuccessListener< Void> (){ @Override public void onSuccess(Void aVoid){ firebaseAuth.signOut(); if(googleApiClient.isConnected()){ Auth.GoogleSignInApi.signOut(googleApiClient); } } }); }@Override protected void onStart() { super.onStart(); googleApiClient.connect(); firebaseAuth.addAuthStateListener(authStateListener); }@Override protected void onStop() { super.onStop(); if(googleApiClient.isConnected()){ googleApiClient.disconnect(); } }@Override public void onBackPressed() { DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout); if (drawer.isDrawerOpen(GravityCompat.START)) { drawer.closeDrawer(GravityCompat.START); } else { super.onBackPressed(); } }//wybieranie fragmentu private void displaySelectedScreen(int itemId) {//creating fragment object Fragment fragment = null; //initializing the fragment object which is selected switch (itemId) { case R.id.nav_menu1: fragment = new Menu1Goals(); break; case R.id.nav_menu2: fragment = new Menu2(); break; case R.id.nav_menu3: fragment = new Menu3(); break; }//replacing the fragment - zmienianie fragmentów //Transakcja fragmentu to seria zmian dotycz?cych fragmentu, które chcemy wykona? w tym samym momencie if (fragment != null) { FragmentTransaction ft = getSupportFragmentManager().beginTransaction(); ft.replace(R.id.content_frame, fragment); ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_FADE); ft.commit(); }DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout); drawer.closeDrawer(GravityCompat.START); }//przekazywanie wybranego fragmentu do interfejsu @SuppressWarnings("StatementWithEmptyBody") @Override public boolean onNavigationItemSelected(MenuItem item) {//calling the method displayselectedscreen and passing the id of selected menu displaySelectedScreen(item.getItemId()); //make this method blank return true; }//------------------------------------Top Menu---------------------------------------------- @Override public boolean onCreateOptionsMenu(Menu menu) {MenuInflater menuInflater = getMenuInflater(); menuInflater.inflate(R.menu.main, menu); //getting the search view from the menu MenuItem searchViewItem = menu.findItem(R.id.menuSearch); //getting search manager from systemservice SearchManager searchManager = (SearchManager) getSystemService(Context.SEARCH_SERVICE); //getting the search view final SearchView searchView = (SearchView) searchViewItem.getActionView(); //you can put a hint for the search input field searchView.setQueryHint("Czego wspólnie poszukamy?"); searchView.setSearchableInfo(searchManager.getSearchableInfo(getComponentName())); //by setting it true we are making it iconified //so the search input will show up after taping the search iconified //if you want to make it visible all the time make it false searchView.setIconifiedByDefault(true); //here we will get the search query searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() { @Override public boolean onQueryTextSubmit(String query) {//do the search here return false; }@Override public boolean onQueryTextChange(String newText) { return false; } }); return true; }@Override public boolean onOptionsItemSelected(MenuItem item) { switch (item.getItemId()){ case R.id.sign_out_button: signOut(); return true; case R.id.action_settings: //settings(); return true; default: return super.onOptionsItemSelected(item); } } //------------------------------------------------------------------------------------------

分段：

public class DailyFragment extends Fragment{Toast toast; private FirebaseFirestore rootRef; private CollectionReference dailyGoalsRef; private String userEmail, userName; @Nullable @Override public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {View layout = inflater.inflate(R.layout.fragment_daily, container, false); FloatingActionButton fab2 = layout.findViewById(R.id.fab2); fab2.setOnClickListener(new View.OnClickListener(){ @Override public void onClick(View view){ AlertDialog.Builder builder = new AlertDialog.Builder(getContext()); builder.setTitle("Zadania na dzisiaj"); final EditText editText = new EditText(getContext()); editText.setInputType(InputType.TYPE_CLASS_TEXT | InputType.TYPE_TEXT_FLAG_CAP_WORDS); editText.setHint("Podaj cel"); editText.setHintTextColor(Color.GRAY); builder.setView(editText); builder.setPositiveButton("Utwórz", new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialogInterface, int i) { Stringnazwa_celu = editText.getText().toString().trim(); addGoalsList(nazwa_celu); } }); builder.setNegativeButton("Anuluj", new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialogInterface, int i) { dialogInterface.dismiss(); } }); AlertDialog alertDialog = builder.create(); alertDialog.show(); } }); dailyGoalsRef = rootRef.collection("goalsData").document(userEmail).collection("dailyGoals"); return layout; }private void addGoalsList(String nazwa_celu){ String goalsListId = dailyGoalsRef.document().getId(); GoalsModel goalsModel = new GoalsModel(goalsListId, nazwa_celu, userName); dailyGoalsRef.document(goalsListId).set(goalsModel).addOnSuccessListener(new OnSuccessListener< Void> () { @Override public void onSuccess(Void aVoid) { Log.d("TAG", "Lista celów stworzona pomy?lnie!"); } }); } }

答案要解决此问题，请更改以下代码行：

if(googleSignInAccount != null){ String userEmail = googleSignInAccount.getEmail(); String userName = googleSignInAccount.getDisplayName(); Toast.makeText(this, "Witaj " + userName, Toast.LENGTH_LONG).show(); }

同

if(googleSignInAccount != null){ userEmail = googleSignInAccount.getEmail(); userName = googleSignInAccount.getDisplayName(); Toast.makeText(this, "Witaj " + userName, Toast.LENGTH_LONG).show(); }

【将列表添加到Cloud Firebase - Android】此字段已声明为全局字段。
您在片段中使用以下代码行：