在我的 Firebase 数据库中，我创建了一个新用户，并为该用户分配了一些值。
但是，我无法获取名称并显示在抽屉导航的标题中。为了清楚起见，我发布了完整的 MainActivity.class。
请帮我解决这个问题，告诉我我做错了什么，我一整天都在做这个。
package com.company.walt.activities;
public class MainActivity extends AppCompatActivity implements IProgressDisplay, ISoftKeyboard, IFirebaseAuth {
// STATIC
private static final String TAG = "MainActivity";
private static final int USER_DASHBOARD = 1;
private static final int PROFILE_MANAGE = 2;
private static final int PROFILE_SETTING = 3;
// FIREBASE
private FirebaseAuth.AuthStateListener mAuthListener;
/*
private FirebaseDatabase firebaseDatabase = FirebaseDatabase.getInstance();
private DatabaseReference databaseReference = firebaseDatabase.getReference();
private DatabaseReference reference = databaseReference.child(getString(R.string.dbnode_users));
*/
DatabaseReference mRootRef = FirebaseDatabase.getInstance().getReference();
DatabaseReference mConditionRef = mRootRef.child("users");
// VARIABLES
private ToggleButton mToogleButton;
private Toolbar mToolbar;
private AccountHeader mHeaderResult = null;
private Drawer mResult = null;
private ProgressBar mProgressBar;
private String currentName = "";
@Override
protected void onCreate(Bundle savedInstanceState) {
if (AppCompatDelegate.getDefaultNightMode() == AppCompatDelegate.MODE_NIGHT_YES) {
setTheme(R.style.NightTheme);
} else {
setTheme(R.style.LightTheme);
}
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
switchAppTheme();
createToolbar();
buildHeader(false, savedInstanceState);
createDrawerBuilder();
mProgressBar = (ProgressBar) findViewById(R.id.progressBar);
}
@Override
protected void onResume() {
super.onResume();
checkAuthenticationState();
}
/**
* Used to check if user is authenticated or not
*/
private void checkAuthenticationState() {
Log.d(TAG, "checkAuthenticationState: checking authentication state.");
FirebaseUser user = FirebaseAuth.getInstance().getCurrentUser();
if (user == null) {
Log.d(TAG, "checkAuthenticationState: user is null, navigating back to login screen.");
Intent intent = new Intent(MainActivity.this, LoginActivity.class);
startActivity(intent);
finish();
} else {
Log.d(TAG, "checkAuthenticationState: user is authenticated.");
}
}
/**
* Used to switch between light and dark mode
*/
public void switchAppTheme() {
mToogleButton = (ToggleButton) findViewById(R.id.switcher);
if (AppCompatDelegate.getDefaultNightMode() == AppCompatDelegate.MODE_NIGHT_YES) {
mToogleButton.setChecked(true);
}
mToogleButton.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
if (isChecked) {
AppCompatDelegate.setDefaultNightMode(AppCompatDelegate.MODE_NIGHT_YES);
restartApp();
} else {
AppCompatDelegate.setDefaultNightMode(AppCompatDelegate.MODE_NIGHT_NO);
restartApp();
}
}
});
}
/**
* Used to create the toolbar on top
*/
private void createToolbar() {
mToolbar = (Toolbar) findViewById(R.id.main_toolbar);
setSupportActionBar(mToolbar);
getSupportActionBar().setTitle(R.string.app_name);
}
/**
* small helper method to reuse the logic to build the AccountHeader
* this will be used to replace the header of the drawer with a compact/normal header
*
* @param compact
* @param savedInstanceState
*/
private void buildHeader(boolean compact, Bundle savedInstanceState) {
IProfile profile;
FirebaseUser user = FirebaseAuth.getInstance().getCurrentUser();
if (user != null) {
String email = user.getEmail();
profile = new ProfileDrawerItem()
.withIdentifier(USER_DASHBOARD)
.withName(getCurrentName())
.withEmail(email)
.withIcon(getResources().getDrawable(R.drawable.ic_user_img));
mHeaderResult = new AccountHeaderBuilder()
.withActivity(this)
.withHeaderBackground(R.drawable.ip_menu_header_bg)
.withCompactStyle(compact)
.addProfiles(
profile,
new ProfileSettingDrawerItem()
.withIdentifier(PROFILE_MANAGE)
.withName("Manage Account")
.withDescription("Manage your details")
.withIcon(new IconicsDrawable(this, GoogleMaterial.Icon.gmd_settings)
.actionBar().colorRes(R.color.material_drawer_dark_primary_text)),
new ProfileSettingDrawerItem()
.withIdentifier(PROFILE_SETTING)
.withName("Add Account")
.withDescription("Register new account")
.withIcon(new IconicsDrawable(this, GoogleMaterial.Icon.gmd_person_add)
.actionBar().colorRes(R.color.material_drawer_dark_primary_text))
)
.withOnAccountHeaderListener(new AccountHeader.OnAccountHeaderListener() {
@Override
public boolean onProfileChanged(View view, IProfile profile, boolean current) {
//sample usage of the onProfileChanged listener
//if the clicked item has the identifier 1 add a new profile ;)
if (profile instanceof IDrawerItem && ((IDrawerItem) profile).getIdentifier() == USER_DASHBOARD) {
// Navigate to home fragment
FragmentManager manager = getSupportFragmentManager();
FragmentTransaction transaction = manager.beginTransaction();
Fragment fragment = new Fragment();
fragment = new HomeFragment();
transaction.replace(R.id.flContent, fragment);
transaction.commit();
}
if (profile instanceof IDrawerItem && ((IDrawerItem) profile).getIdentifier() == PROFILE_MANAGE) {
// Navigate to home fragment
FragmentManager manager = getSupportFragmentManager();
FragmentTransaction transaction = manager.beginTransaction();
Fragment fragment = new Fragment();
fragment = new AccountFragment();
transaction.replace(R.id.flContent, fragment);
transaction.commit();
} else if (profile instanceof IDrawerItem && ((IDrawerItem) profile).getIdentifier() == PROFILE_SETTING) {
Toast.makeText(MainActivity.this, "ACCOUNT", Toast.LENGTH_SHORT).show();
}
return false;
}
})
.build();
}
}
/**
* Used to create the drawer with all the icons and items
*/
private void createDrawerBuilder() {
//create the drawer and remember the `Drawer` mResult object
mResult = new DrawerBuilder()
.withActivity(this)
.withAccountHeader(mHeaderResult)
.withToolbar(mToolbar)
.addDrawerItems(
new SecondaryDrawerItem().withName("1st")
.withIdentifier(1)
.withIconTintingEnabled(true)
.withIcon(new IconicsDrawable(this, GoogleMaterial.Icon.gmd_device_hub))
.withTag("Bullhorn"),
new SecondaryDrawerItem().withName("2nd")
.withIdentifier(2)
.withIconTintingEnabled(true)
.withIcon(new IconicsDrawable(this, GoogleMaterial.Icon.gmd_shopping_cart))
.withTag("Bullhorn"),
new SecondaryDrawerItem().withName("3rd")
.withIdentifier(3)
.withIconTintingEnabled(true)
.withIcon(new IconicsDrawable(this, GoogleMaterial.Icon.gmd_camera_roll))
.withTag("Bullhorn"),
new SecondaryDrawerItem().withName("4th")
.withIdentifier(4)
.withIconTintingEnabled(true)
.withIcon(new IconicsDrawable(this, GoogleMaterial.Icon.gmd_content_copy))
.withTag("Bullhorn"),
new SecondaryDrawerItem().withName("5th")
.withIdentifier(5)
.withIconTintingEnabled(true)
.withIcon(new IconicsDrawable(this, GoogleMaterial.Icon.gmd_folder_open))
.withTag("Bullhorn"),
new SectionDrawerItem().withName(R.string.drawer_section_header).withEnabled(false),
new SecondaryDrawerItem().withName("6th")
.withIdentifier(6)
.withIconTintingEnabled(true)
.withIcon(new IconicsDrawable(this, GoogleMaterial.Icon.gmd_settings))
.withTag("Bullhorn"),
new SecondaryDrawerItem().withName("7th")
.withIdentifier(7)
.withIconTintingEnabled(true)
.withIcon(new IconicsDrawable(this, GoogleMaterial.Icon.gmd_headset_mic))
.withTag("Bullhorn"),
new SecondaryDrawerItem().withName("8th")
.withIdentifier(8)
.withIconTintingEnabled(true)
.withIcon(new IconicsDrawable(this, GoogleMaterial.Icon.gmd_security))
.withTag("Bullhorn"),
new SecondaryDrawerItem().withName("9th")
.withIdentifier(9)
.withIconTintingEnabled(true)
.withIcon(new IconicsDrawable(this, GoogleMaterial.Icon.gmd_power_settings_new))
.withTag("Bullhorn")
)
.withOnDrawerItemClickListener(new Drawer.OnDrawerItemClickListener() {
@Override
public boolean onItemClick(View view, int position, IDrawerItem drawerItem) {
navigateDrawerItem((int) drawerItem.getIdentifier(), drawerItem);
return true;
}
})
.addStickyDrawerItems(
new SecondaryDrawerItem().withName(R.string.drawer_all_right_reserved).withIcon(FontAwesome.Icon.faw_copyright).withEnabled(false)
).build();
}
/**
* Used to navigate to drawer fragment items
*/
public void navigateDrawerItem(int pos, IDrawerItem drawerItem) {
// Create a new fragment and specify the fragment to show based on nav item clicked
Fragment fragment = null;
Class fragmentClass;
switch (pos) {
case 1:
fragmentClass = Fragment1.class;
break;
case 2:
fragmentClass = Fragment2.class;
break;
case 3:
fragmentClass = Fragment3.class;
break;
case 4:
fragmentClass = Fragment4.class;
break;
case 5:
fragmentClass = Fragment5.class;
break;
case 6:
fragmentClass = Fragment6.class;
break;
case 7:
fragmentClass = Fragment7.class;
break;
case 8:
fragmentClass = Fragment8.class;
break;
case 9:
fragmentClass = HomeFragment.class;
signOut();
restartApp();
break;
default:
fragmentClass = HomeFragment.class;
}
try {
fragment = (Fragment) fragmentClass.newInstance();
} catch (Exception e) {
e.printStackTrace();
}
// Insert the fragment by replacing any existing fragment
FragmentManager fragmentManager = getSupportFragmentManager();
fragmentManager.beginTransaction().replace(R.id.flContent, fragment).commit();
mResult.closeDrawer();
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle item selection
switch (item.getItemId()) {
default:
return super.onOptionsItemSelected(item);
}
}
@Override
protected void onSaveInstanceState(Bundle outState) {
//add the values which need to be saved from the drawer to the bundle
outState = mResult.saveInstanceState(outState);
//add the values which need to be saved from the accountHeader to the bundle
outState = mHeaderResult.saveInstanceState(outState);
super.onSaveInstanceState(outState);
}
@Override
public void onBackPressed() {
//handle the back press :D close the drawer first and if the drawer is closed close the activity
if (mResult != null && mResult.isDrawerOpen()) {
mResult.closeDrawer();
} else {
super.onBackPressed();
}
}
/**
* Sign out from application
*/
private void signOut() {
Log.d(TAG, "signOut: signing out");
FirebaseAuth.getInstance().signOut();
}
/**
* Used to restart the application
*/
private void restartApp() {
Intent intent = new Intent(getApplicationContext(), MainActivity.class);
startActivity(intent);
finish();
}
@Override
protected void onStart() {
super.onStart();
Query query = mConditionRef.orderByKey().equalTo(FirebaseAuth.getInstance().getCurrentUser().getUid());
query.addListenerForSingleValueEvent(new ValueEventListener() {
@Override
public void onDataChange(DataSnapshot dataSnapshot) {
for (DataSnapshot singelSnapshot : dataSnapshot.getChildren())
{
User user = singelSnapshot.getValue(User.class);
setCurrentName(user.getName());
Log.d(TAG, "onDataChange: found user: " + user.toString());
}
}
@Override
public void onCancelled(DatabaseError databaseError) {
}
});
}
@Override
protected void onStop() {
super.onStop();
}
/*
* **********************************************************************************************
* GET & SET
* */
public String getCurrentName() {
return this.currentName;
}
//public method to set the age variable
public void setCurrentName(String name) {
this.currentName = name;
}
/*
* **********************************************************************************************
* INTERFACE METHODS
* */
/**
* Display progressbar
*/
public void showProgress() {
findViewById(R.id.progressBar).setVisibility(View.VISIBLE);
}
/**
* Hide progressbar
*/
public void hideProgress() {
if (mProgressBar.getVisibility() == View.VISIBLE) {
findViewById(R.id.progressBar).setVisibility(View.INVISIBLE);
}
}
/**
* Hide softKeyboard
*/
public void hideSoftKeyboard() {
this.getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_HIDDEN);
}
/*
* **********************************************************************************************
* FIREBASE SETUP
* */
/**
* Firebase Auth
*/
public void setupFirebaseAuth() {
mAuthListener = new FirebaseAuth.AuthStateListener() {
@Override
public void onAuthStateChanged(@NonNull FirebaseAuth firebaseAuth) {
FirebaseUser user = firebaseAuth.getCurrentUser();
if (user != null) {
// User is signed in
Log.d(TAG, "onAuthStateChanged:signed_in:" + user.getUid());
//toastMessage("Successfully signed in with: " + user.getEmail());
} else {
// User is signed out
Log.d(TAG, "onAuthStateChanged:signed_out");
Toast.makeText(MainActivity.this, "Signed out", Toast.LENGTH_SHORT).show();
Intent intent = new Intent(MainActivity.this, LoginActivity.class);
startActivity(intent);
}
}
};
}
}
这是 LogCat 中的输出
01-01 20:30:24.294 4992-4992/com.company.walt D/MainActivity: onDataChange: found user: User{name='Ben Solo', phone='0997755223311', profile_img='', user_id='D1lXejIFjNTcRr87PAI8rdjm7Wt2'}
最佳答案
与其他同步方法调用不同，onDataChange 方法是异步的。
这意味着监听器声明之后的代码很可能会在 onDataChange 获取调用并设置用户名之前运行。这将导致您的名字在显示中为空
将当前用户代码转移到setCurrentName方法
setCurrentName(String name){
currentUser = new ProfileDrawerItem()
.withIdentifier(USER_DASHBOARD)
// Using name passed by onDataChange
.withName(name)
.withEmail(email)
.withIcon(getResources().getDrawable(R.drawable.ic_user_img));
}
现在，当 onDataChange 被调用时，您的显示器将获得名称，并且应该根据您的逻辑进行更新
关于java - Firebase 无法显示实时数据库中的名称，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/48052852/