按钮和 Firebase 侦听器 - 未调用 OnDataChange - Android

Question

我们正在为与 FIREBASE 接口的 LOGIN 开发一个 Activity。 我们有一个带有 OnClickListener 的按钮，其中嵌套了 DatabaseRefence 上的 AddValueListener 问题是 AddValueListener 永远不会被调用，而且如果我们使用锁存器，应用程序将冻结，因为锁存器永远不会降为零 但是，如果我们在 AddValueListener 下注释代码，我们的应用程序将在其中输入它并且它可以工作。

我们做错了什么？

   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 也给了我们这个带有 Async 的子类，也许我们需要用这个？以及如何？

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;
    }

谢谢

Answer 1

如果您想使用 firebase 登录，则可以使用我的代码。希望对你有帮助。

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;
}

}