按鈕和Firebase監聽器 - OnDataChange不叫 - Android

Question

我們正在爲與FIREBASE接口的LOGIN開發一個Activity。 我們有一個OnClickListener按鈕，其中的AddValueListener嵌套在DatabaseRefence上 問題是AddValueListener永遠不會被調用，並且如果我們使用鎖存器，應用程序將凍結，因爲鎖存器永遠不會降爲零 BUT如果我們在AddValueListener下注釋代碼，我們的應用程序將進入它並且它可以工作。

我們在做什麼錯了？

package it.polito.mad17.viral.sliceapp; 

    import android.animation.Animator; 
    import android.animation.AnimatorListenerAdapter; 
    import android.annotation.TargetApi; 
    import android.content.pm.PackageManager; 
    import android.support.annotation.NonNull; 
    import android.support.design.widget.Snackbar; 
    import android.support.v7.app.AppCompatActivity; 
    import android.app.LoaderManager.LoaderCallbacks; 

    import android.content.CursorLoader; 
    import android.content.Loader; 
    import android.database.Cursor; 
    import android.net.Uri; 
    import android.os.AsyncTask; 

    import android.os.Build; 
    import android.os.Bundle; 
    import android.provider.ContactsContract; 
    import android.telephony.PhoneNumberUtils; 
    import android.text.TextUtils; 
    import android.util.Log; 
    import android.view.KeyEvent; 
    import android.view.View; 
    import android.view.View.OnClickListener; 
    import android.view.inputmethod.EditorInfo; 
    import android.widget.ArrayAdapter; 
    import android.widget.AutoCompleteTextView; 
    import android.widget.Button; 
    import android.widget.EditText; 
    import android.widget.TextView; 
    import android.widget.Toast; 

    import com.google.firebase.database.DataSnapshot; 
    import com.google.firebase.database.DatabaseError; 
    import com.google.firebase.database.DatabaseReference; 
    import com.google.firebase.database.FirebaseDatabase; 
    import com.google.firebase.database.ValueEventListener; 

    import java.util.ArrayList; 
    import java.util.List; 
    import java.util.Objects; 
    import java.util.concurrent.CountDownLatch; 
    import java.util.concurrent.Semaphore; 
    import java.util.regex.Pattern; 
    import java.lang.String; 

    import static android.Manifest.permission.READ_CONTACTS; 

    /** 
    * A login screen that offers login via email/password. 
    */ 
    public class LoginActivity extends AppCompatActivity implements LoaderCallbacks<Cursor> { 


    /** 
    * Id to identity READ_CONTACTS permission request. 
    */ 
    private static final int REQUEST_READ_CONTACTS = 0; 

    /** 
    * A dummy authentication store containing known user names and passwords. 
    * TODO: remove after connecting to a real authentication system. 
    */ 
    private static final String[] DUMMY_CREDENTIALS = new String[]{ 
      "foo@example.com:hello", "bar@example.com:world" 
    }; 
    /** 
    * Keep track of the login task to ensure we can cancel it if requested. 
    */ 
    private UserLoginTask mAuthTask = null; 

    // UI references. 
    private AutoCompleteTextView mPhoneView; 
    private EditText mPasswordView; 
    private View mProgressView; 
    private View mLoginFormView; 
    private String pwdDB,phoneDB; 
    private boolean cancel = false; 
    private View focusView = null; 
    private boolean flag=false; 
    private DatabaseReference db; 

    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_login); 
     //Firebase.setAndroidContext(this); 
     // Set up the login form. 
     mPhoneView = (AutoCompleteTextView) findViewById(R.id.phoneNumber); 
     populateAutoComplete(); 

     mPasswordView = (EditText) findViewById(R.id.password); 
     mPasswordView.setOnEditorActionListener(new TextView.OnEditorActionListener() { 
      @Override 
      public boolean onEditorAction(TextView textView, int id, KeyEvent keyEvent) { 
       if (id == R.id.login || id == EditorInfo.IME_NULL) { 
        attemptLogin(); 
        return true; 
       } 
       return false; 
      } 
      }); 
    } 

    private void attemptLogin() { 
     if (mAuthTask != null) { 
      return; 
     } 

     // Reset errors. 
     mPhoneView.setError(null); 
     mPasswordView.setError(null); 

     // Store values at the time of the login attempt. 
     final String phone = mPhoneView.getText().toString(); 
     final String password = mPasswordView.getText().toString(); 


     boolean verifyMail = false; 


     // Check for a valid phone number. 
     if (phone.isEmpty()) { 
      mPhoneView.requestFocus(); 
      mPhoneView.setError(getString(R.string.error_field_required)); 
      return; 
     } 
     if (isPhoneValid(phone) == false) { 
      mPhoneView.requestFocus(); 
      mPhoneView.setError(getString(R.string.error_invalid_phone)); 
      return; 
      ////focusView = mPhoneView; 
      // cancel = true; 
     } 

     // Check for a valid password, if the user entered one. 
     if (TextUtils.isEmpty(password)) { 
      mPasswordView.requestFocus(); 
      mPasswordView.setError(getString(R.string.error_empty_password)); 
      return; 
     } 
     //Check for a password having the right length 
     //  8 >= pwd <= 16 
     if (isPasswordValid(password) == false) { 
      mPasswordView.requestFocus(); 
      mPasswordView.setError(getString(R.string.error_short_password)); 
      return; 
     } 


     final CountDownLatch latch = new CountDownLatch(1); 
     db = FirebaseDatabase.getInstance("https://sliceapp-a55d6.firebaseio.com/").getReference(); 

     System.out.println("AAAAA " + db.child("Users").child(phone).toString()); 

     //  Thread t = new Thread(new Runnable() { 
     //  @Override 
     //  public void run() { 
     db.child("Users").addListenerForSingleValueEvent(new ValueEventListener() { 

      @Override 
      public void onDataChange(DataSnapshot dataSnapshot) { 
       Log.d("BEFORE FOR CYCLE", "CIAO"); 
//Log are never shown 
       for (DataSnapshot d : dataSnapshot.getChildren()) { 
        System.out.println("CCCCC " + d.getKey()); 
        if (d.getKey().equals(phone)) { 
         phoneDB = d.getKey(); 
         System.out.println("Phone Number is " + phoneDB); 
         pwdDB = d.child("password").getValue().toString(); 
         System.out.println("The password is " + pwdDB); 
        } 
       } 
       // latch.countDown(); 
      } 

      @Override 
      public void onCancelled(DatabaseError databaseError) { 
       Log.d("FAILURE", databaseError.toString()); 
      } 

     }); 

    //} 

    // }); 



     // t.start(); 

     // try { 
      // latch.await(); 
      // } catch (InterruptedException e) { 
      // e.printStackTrace(); 
      //} 

    //If we comment all this code the listener is called 

      System.out.println("phoneDB: " + phoneDB + " pwdDB: " + pwdDB); 
     if(phoneDB.isEmpty()){ 
      mPhoneView.requestFocus(); 
      mPhoneView.setError("The phone number field is empty!"); 
      return; 
     }else if(!phoneDB.equals(phone)){ 
      mPhoneView.requestFocus(); 
      mPhoneView.setError("The phone number is wrong!"); 
      return; 
     } 

     if(pwdDB.isEmpty()){ 
      mPasswordView.requestFocus(); 
      mPasswordView.setError("The password field is empty!"); 
      return; 
     }else if(!pwdDB.equals(password)){ 
      mPasswordView.requestFocus(); 
      mPasswordView.setError("The password is wrong!"); 
      return; 
     } 

    // System.out.println("phoneDB: " + phoneDB + " pwdDB: " + pwdDB); 

    } 

Android studio也給我們這個子類與Async，也許我們需要使用它？如何？

public class UserLoginTask extends AsyncTask<Void, Void, Boolean> { 

     private final String mPhone; 
     private final String mPassword; 

    UserLoginTask(String phone, String password) { 
     mPhone = phone; 
     mPassword = password; 
    } 

    @Override 
    protected Boolean doInBackground(Void... params) { 
     // TODO: attempt authentication against a network service. 

     try { 
      // Simulate network access. 
      Thread.sleep(2000); 
     } catch (InterruptedException e) { 
      return false; 
     } 

     for (String credential : DUMMY_CREDENTIALS) { 
      String[] pieces = credential.split(":"); 
      if (pieces[0].equals(mPhone)) { 
       // Account exists, return true if the password matches. 
       return pieces[1].equals(mPassword); 
      } 
     } 

     // TODO: register the new account here. 
     return true; 
    } 

感謝

Answer 1

如果你想與火力點登錄，那麼你可以使用我的代碼。我希望它能幫助你。

public class Login extends AppCompatActivity implements View.OnClickListener { 

static final String TAG = "FCM"; 

// [START declare_auth_listener] 
private FirebaseAuth.AuthStateListener mAuthListener; 
FirebaseUser user; 
// check if GPS enabled 
private String myID, userUid; 
CallbackManager callbackManager; 
private FirebaseAuth mAuth; 
private String android_id; 
private DatabaseReference myRef; 
DatabaseReference myDBRef; 
@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_login); 
    preferences = getSharedPreferences(check.PREFERENCES, Context.MODE_PRIVATE); 
    strToken = preferences.getString(DEVICETOKEN, "").toString(); 
    gpsTracker = new GPSTracker(Login.this); 
    txtLogin = (TextView) findViewById(R.id.login_btn); 
    //setOnClick listner 
    txtLogin.setOnClickListener(this); 
    android_id = Settings.Secure.getString(getContentResolver(), Settings.Secure.ANDROID_ID); 
    mAuth = FirebaseAuth.getInstance(); 
     getUserToken(); 
    txtRegister.setTypeface(check.NeueRegular); 
      myRef = FirebaseDatabase.getInstance().getReference("localID"); 
    myDBRef = FirebaseDatabase.getInstance().getReference(); 
    mAuthListener = new FirebaseAuth.AuthStateListener() { 
     @Override 
     public void onAuthStateChanged(@NonNull FirebaseAuth firebaseAuth) { 
      FirebaseUser user = firebaseAuth.getCurrentUser(); 
      if (user != null) { 
       myRef.child(android_id).setValue(user.getEmail()); 
       // User is signed in 
       Log.d(TAG, "on Auth State Changed : signed_in : " + user.getEmail()); 
      } else { 
       // User is signed out 
       Log.d(TAG, "on Auth State Changed : signed_out"); 
      } 
        } 
    }; 

} 
@Override 
public void onStart() { 
    super.onStart(); 
    mAuth.addAuthStateListener(mAuthListener); 
} 

@Override 
public void onStop() { 
    super.onStop(); 
    if (mAuthListener != null) { 
     mAuth.removeAuthStateListener(mAuthListener); 
    } 
} 


@Override 
public void onClick(View v) { 
    switch (v.getId()) {   

     case R.id.login_btn:    
         signIn(strEmail, strPassword); 
      break; 
    } 
} 
private void signIn(String email, String password) { 
    Log.d(TAG, "signIn:" + email); 
    if (!validateForm()) { 
     return; 
    } 
    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 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(Login.this, "failed auth..", 
           Toast.LENGTH_SHORT).show(); 
        }else { 


        } 
       } 
      }); 
    // [END sign_in_with_email] 
} 
private void getUserToken() { 
    if (user != null) { 
     userUid = user.getUid(); 
    } 
} 

private boolean validateForm() { 
    boolean valid = true; 

    String emails = edit_email.getText().toString(); 
    if (TextUtils.isEmpty(emails)) { 
     edit_email.setError("Required."); 
     valid = false; 
    } else { 
     edit_email.setError(null); 
    } 
    String passwords = edit_password.getText().toString(); 
    if (TextUtils.isEmpty(passwords)) { 
     edit_password.setError("Required."); 
     valid = false; 
    } else { 
     edit_password.setError(null); 
    } 

    return valid; 
} 

}