我是firebase的新手，但我设法使用firebase开发应用程序 - 电子邮件和密码验证 这个应用程序适用于组织的成员，所以没有在应用程序上注册，组织给我一个列表，我添加到用户列表。我的问题是，我只有45个注册用户，但几乎有85谁正在使用该应用程序。我明白我应该使用身份验证令牌，但我不太清楚。任何人都可以解释我可以同时防止多次登录的最简单方法吗？ 我已经附加了登录代码（我尝试存储设备名称，但这是一种不好的方式）所以有人可以帮我解决必须做的事情吗？
public class EmailLogin extends AppCompatActivity implements
View.OnClickListener {
public String Email;
private static final String TAG = "EmailPassword";
public static int device = 0;
private TextView forgoPwd;
private TextView mDetailTextView;
private EditText mEmailField;
private EditText mPasswordField;
private ProgressDialog PD;
private CheckBox saveLoginCheckBox;
private SharedPreferences loginPreferences;
private SharedPreferences.Editor loginPrefsEditor;
private Boolean saveLogin;
// [START declare_auth]
private FirebaseAuth mAuth;
// [END declare_auth]
private DatabaseReference root;
// [START declare_auth_listener]
private FirebaseAuth.AuthStateListener mAuthListener;
// [END declare_auth_listener]
private String temp_key;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
WindowManager.LayoutParams.FLAG_FULLSCREEN);
setContentView(R.layout.emailpass);
PD = new ProgressDialog(this);
PD.setMessage("Loading...");
PD.setCancelable(true);
PD.setCanceledOnTouchOutside(false);
// Views
mEmailField = (EditText) findViewById(R.id.field_email);
Email = mEmailField.toString();
mPasswordField = (EditText) findViewById(R.id.field_password);
Button btnCount = (Button) findViewById(R.id.email_sign_in_button);
// Button regis = (Button) findViewById(R.id.regis);
saveLoginCheckBox = (CheckBox)findViewById(R.id.checkBox);
loginPreferences = getSharedPreferences("loginPrefs", MODE_PRIVATE);
loginPrefsEditor = loginPreferences.edit();
saveLogin = loginPreferences.getBoolean("saveLogin", false);
if (saveLogin == true) {
mEmailField.setText(loginPreferences.getString("username", ""));
mPasswordField.setText(loginPreferences.getString("password", ""));
saveLoginCheckBox.setChecked(true);
}
//regis.setOnClickListener(this);
forgoPwd = (TextView)findViewById(R.id.forgo);
forgoPwd.setOnClickListener(this);
// Buttons
btnCount.setOnClickListener(this);
// findViewById(R.id.email_create_account_button).setOnClickListener(this);
// findViewById(R.id.sign_out_button).setOnClickListener(this);
// [START initialize_auth]
mAuth = FirebaseAuth.getInstance();
// [END initialize_auth]
// [START auth_state_listener]
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());
} else {
// User is signed out
Log.d(TAG, "onAuthStateChanged:signed_out");
}
// [START_EXCLUDE]
updateUI(user);
// [END_EXCLUDE]
}
};
// [END auth_state_listener]
}
public ProgressDialog mProgressDialog;
public void showProgressDialog() {
if (mProgressDialog == null) {
mProgressDialog = new ProgressDialog(this);
mProgressDialog.setMessage(getString(R.string.loading));
mProgressDialog.setIndeterminate(true);
}
}
public void hideProgressDialog() {
if (mProgressDialog != null && mProgressDialog.isShowing()) {
mProgressDialog.dismiss();
}
}
// [START on_start_add_listener]
@Override
public void onStart() {
super.onStart();
mAuth.addAuthStateListener(mAuthListener);
}
// [END on_start_add_listener]
// [START on_stop_remove_listener]
@Override
public void onStop() {
super.onStop();
if (mAuthListener != null) {
mAuth.removeAuthStateListener(mAuthListener);
}
}
// [END on_stop_remove_listener]
private void createAccount(String email, String password) {
Log.d(TAG, "createAccount:" + email);
if (!validateForm()) {
return;
}
showProgressDialog();
// [START create_user_with_email]
mAuth.createUserWithEmailAndPassword(email, password)
.addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {
@Override
public void onComplete(@NonNull Task<AuthResult> task) {
Log.d(TAG, "createUserWithEmail:onComplete:" + task.isSuccessful());
// If sign in fails, display a message to the user. If sign in succeeds
// the auth state listener will be notified and logic to handle the
// signed in user can be handled in the listener.
if (!task.isSuccessful()) {
Toast.makeText(EmailLogin.this, R.string.auth_failed,
Toast.LENGTH_SHORT).show();
}
// [START_EXCLUDE]
hideProgressDialog();
// [END_EXCLUDE]
}
});
// [END create_user_with_email]
}
private void signIn(String email, String password) {
Log.d(TAG, "signIn:" + email);
if (saveLoginCheckBox.isChecked()) {
loginPrefsEditor.putBoolean("saveLogin", true);
loginPrefsEditor.putString("username", mEmailField.getText().toString());
loginPrefsEditor.putString("password", password);
loginPrefsEditor.commit();
} else {
loginPrefsEditor.clear();
loginPrefsEditor.commit();
}
if (!validateForm()) {
return;
}
PD.show();
showProgressDialog();
// [START sign_in_with_email]
mAuth.signInWithEmailAndPassword(email, password)
.addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {
@Override
public void onComplete(@NonNull Task<AuthResult> task) {
Log.d(TAG, "signInWithEmail:onComplete:" + task.isSuccessful());
if (task.isSuccessful())
{
onAuthSuccess(task.getResult().getUser());
}
// If sign in fails, display a message to the user. If sign in succeeds
// the auth state listener will be notified and logic to handle the
// signed in user can be handled in the listener.
if (!task.isSuccessful()) {
Log.w(TAG, "signInWithEmail:failed", task.getException());
Toast.makeText(EmailLogin.this, R.string.auth_failed,
Toast.LENGTH_SHORT).show();
}
// [START_EXCLUDE]
if (!task.isSuccessful()) {
// mStatusTextView.setText(R.string.auth_failed);
}PD.dismiss();
hideProgressDialog();
// [END_EXCLUDE]
}
});
// [END sign_in_with_email]
}
private void onAuthSuccess(FirebaseUser user) {
if (device == 0)
getDeviceName();
device++;
String username = usernameFromEmail(user.getEmail());
Intent intent = new Intent(getApplicationContext(),Home_screen.class);
intent.putExtra("user",username);
startActivity(intent);
finish();
}
public String getDeviceName() {
String manufacturer = Build.MANUFACTURER;
String model = Build.MODEL;
root = FirebaseDatabase.getInstance().getReference().child("users");
doDb(manufacturer);
return manufacturer+model ;
}
private void doDb(String manu) {
Map<String,Object> map = new HashMap<String, Object>();
temp_key = root.push().getKey();
root.updateChildren(map);
DatabaseReference mess_root = root.child(temp_key);
Map<String,Object> map2 = new HashMap<String, Object>();
String email = FirebaseAuth.getInstance().getCurrentUser().getEmail();
int index = email.indexOf('@');
email = email.substring(0,index);
map2.put("user",email);
map2.put("msg",manu);
mess_root.updateChildren(map2);
}
private String usernameFromEmail(String email) {
if (email.contains("@")) {
return email.split("@")[0];
} else {
return email;
}
}
private void signOut() {
mAuth.signOut();
updateUI(null);
}
private boolean validateForm() {
boolean valid = true;
String email = mEmailField.getText().toString();
if (TextUtils.isEmpty(email)) {
mEmailField.setError("Required.");
valid = false;
} else {
mEmailField.setError(null);
}
String password = mPasswordField.getText().toString();
if (TextUtils.isEmpty(password)) {
mPasswordField.setError("Required.");
valid = false;
} else {
mPasswordField.setError(null);
}
return valid;
}
private void updateUI(FirebaseUser user) {
hideProgressDialog();
if (user != null) {
//Timer timer = new Timer();
//timer.schedule(new TimerTask(){
// public void run() {
Intent i = new Intent(EmailLogin.this, Home_screen.class);
i.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(i);
finish();
// return;
// }
// }, 600000);
}
/*
if (user != null) {
Intent intent = new Intent(getApplicationContext(),Home_screen.class);
startActivity(intent);
finish();
mStatusTextView.setText(getString(R.string.emailpassword_status_fmt, user.getEmail()));
mDetailTextView.setText(getString(R.string.firebase_status_fmt, user.getUid()));
findViewById(R.id.email_password_buttons).setVisibility(View.GONE);
findViewById(R.id.email_password_fields).setVisibility(View.GONE);
} */
else {
// mStatusTextView.setText(R.string.signed_out);
// mDetailTextView.setText(null);
// findViewById(R.id.email_password_buttons).setVisibility(View.VISIBLE);
// findViewById(R.id.email_password_fields).setVisibility(View.VISIBLE);
}
}
@Override
public void onClick(View v) {
int i = v.getId();
if (i == R.id.email_sign_in_button) {
signIn(mEmailField.getText().toString(), mPasswordField.getText().toString());
}
//if(i == R.id.regis)
{
}
if(i == R.id.forgo) {
FirebaseAuth auth = FirebaseAuth.getInstance();
String mail = mEmailField.getText().toString();
if (TextUtils.isEmpty(mail)) {
mEmailField.setError("Required.");
} else {
auth.sendPasswordResetEmail(mEmailField.getText().toString())
.addOnCompleteListener(new OnCompleteListener<Void>() {
@Override
public void onComplete(@NonNull Task<Void> task) {
if (task.isSuccessful()) {
Toast.makeText(EmailLogin.this, "Email sent to your account",
Toast.LENGTH_SHORT).show();
}
}
});
}
}
}
}
答案 0 :(得分：0)
我知道我应该使用身份验证令牌
那不行。每当用户登录设备时，他们都会获得新的身份验证令牌。因此，在两个设备上登录的同一用户将具有不同的身份验证令牌。
但他们将拥有相同的UID。所以我实际上存储了uid以及识别数据库中活动设备的东西。
activeDeviceByUser
<uid>: <device ID>
答案 1 :(得分：0)
您可以聘用会话管理器，它仅跟踪上一个会话并终止该用户的所有其他会话。一种简单的方法是在每次启动应用程序时在客户端上生成UUID（随机128位值）并将其称为sessionId。如果用户已登录，或者当登录时，请将sessionId写入数据库中当前用户userId下名为lastSessionId的数据库中。然后，只需侦听当前lastSessionId对userId（在客户端）的更改即可。
当另一个客户端使用相同的userId启动您的应用程序时，该客户端也会获得一个随机的sessionId，并且该sessionId也会被写入该userId下的数据库中（覆盖最后一个客户端的写操作）。然后，向userId登录的所有客户端（通过文档侦听器）通知lastSessionId的更改，对于本地sessionId与远程{{1 }}，它们的UX会得到相应处理。您可以优雅地退出这些客户端，或者更严重地终止他们的应用程序，并出现致命错误。