即使我使用Parse sdk注销，getCurrentUser也不会为null

Question

Splash.Java

import android.content.Intent;
import android.os.Handler;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;

import com.parse.Parse;
import com.parse.ParseUser;

public class Splash extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_splash);
        new Handler().postDelayed(new Runnable() {

            @Override
            public void run() {
                final ParseUser user = ParseUser.getCurrentUser();
                if (user != null) {
                    // Start an intent for the logged in activity
                    startActivity(new Intent(Splash.this, MainActivity.class));
                } else {
                    // Start and intent for the logged out activity
                    startActivity(new Intent(Splash.this, LoginActivity.class));
                }
            }
        }, 3000);
    }

}

LoginActivity.java

import android.app.ProgressDialog;
import android.content.Intent;
import android.os.Bundle;
import android.provider.ContactsContract;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;

import com.parse.LogInCallback;
import com.parse.ParseException;
import com.parse.ParseUser;

import butterknife.ButterKnife;
import butterknife.InjectView;

public class LoginActivity extends AppCompatActivity {
    private static final String TAG = "LoginActivity";
    private static final int REQUEST_SIGNUP = 0;

    @InjectView(R.id.input_username)
    EditText _usernameText;
    @InjectView(R.id.input_password)
    EditText _passwordText;
    @InjectView(R.id.btn_login)
    Button _loginButton;
    @InjectView(R.id.link_signup)
    TextView _signInLink;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_login);
        ButterKnife.inject(this);


        _loginButton.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {
                login();
            }
        });

        _signInLink.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {
                // Start the Signup activity
                Intent intent = new Intent(LoginActivity.this, SignupActivity.class);
                startActivity(intent);
            }
        });
    }

    public void login() {
        Log.d(TAG, "Login");

        if (!validate()) {
            onLoginFailed();
            return;
        }

        _loginButton.setEnabled(false);

        final ProgressDialog progressDialog = new ProgressDialog(LoginActivity.this,
                R.style.AppTheme_Dark_Dialog);
        progressDialog.setIndeterminate(true);
//        progressDialog.setMessage("Authenticating...");
        progressDialog.show();
        new android.os.Handler().postDelayed(
                new Runnable() {
                    public void run() {
                        onLoginSuccess();
                        progressDialog.dismiss();
                    }
                }, 3000);
    }

    void onLoginSuccess() {

        // TODO: Authentication Source

        ParseUser.logInInBackground(_usernameText.getText().toString(),
                _passwordText.getText().toString(), new LogInCallback() {
                    @Override
                    public void done(ParseUser parseUser, ParseException e) {
                        if (parseUser != null) {
                            moveTaskToBack(false);
                            Toast.makeText(LoginActivity.this, "Logged in Successfully!!", Toast.LENGTH_SHORT).show();
                            Intent intent = new Intent(LoginActivity.this, MainActivity.class);
                            intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK |
                                    Intent.FLAG_ACTIVITY_NEW_TASK);
                            startActivity(intent);
                        } else {

                            Toast.makeText(LoginActivity.this, "\n Enter correct user credentials.",
                                    Toast.LENGTH_LONG).show();
                            _loginButton.setEnabled(true);
                        }
                    }
                });
    }


    void onLoginFailed() {
        _passwordText.getText().clear();
        _usernameText.getText().clear();
        Toast.makeText(LoginActivity.this, "Login Failed!!", Toast.LENGTH_SHORT).show();
    }

    public boolean validate() {
        boolean valid = true;

        String username = _usernameText.getText().toString();
        String password = _passwordText.getText().toString();

        if (username.isEmpty()) {
            _usernameText.setError("enter a valid username");
            Toast.makeText(LoginActivity.this, "Enter a valid username!", Toast.LENGTH_SHORT).show();
            valid = false;

        } else {
            _usernameText.setError(null);
        }

        if (password.isEmpty() || password.length() < 4 || password.length() > 10) {
            _passwordText.setError("between 4 and 10 alphanumeric characters");
            Toast.makeText(LoginActivity.this, "Enter a valid Password!", Toast.LENGTH_SHORT).show();
            valid = false;
        } else {
            _passwordText.setError(null);
        }

        return valid;
    }
}

MainActivity.java

import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.support.design.widget.NavigationView;
import android.support.v4.view.GravityCompat;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBarDrawerToggle;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Button;
import android.widget.Toast;
import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.OnMapReadyCallback;
import com.google.android.gms.maps.SupportMapFragment;
import com.google.android.gms.maps.model.BitmapDescriptorFactory;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.MarkerOptions;
import com.parse.ParseUser;


public class MainActivity extends AppCompatActivity
        implements NavigationView.OnNavigationItemSelectedListener, OnMapReadyCallback {
    Button button_offer_ride;
    Button button_find_ride;
    private GoogleMap mMap;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);
        //map start
        SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()
                .findFragmentById(R.id.map);
        mapFragment.getMapAsync(this);
        //map stop

        button_find_ride=(Button) findViewById(R.id.btn_findride);
        button_offer_ride=(Button) findViewById(R.id.btn_offerride);

        String user=ParseUser.getCurrentUser().getUsername();
        Toast.makeText(MainActivity.this, user, Toast.LENGTH_SHORT).show();

        button_find_ride.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent inten_onClick_findride=new Intent(MainActivity.this,FindActivity.class);
                startActivity(inten_onClick_findride);
            }
        });

        button_offer_ride.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent inten_onClick_Offerride=new Intent(MainActivity.this,OfferActivity.class);
                startActivity(inten_onClick_Offerride);
            }
        });


        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);

    }

    @Override
    public void onBackPressed() {
        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        if (drawer.isDrawerOpen(GravityCompat.START)) {
            drawer.closeDrawer(GravityCompat.START);
        } else {
            super.onBackPressed();
        }
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }
        if(id == R.id.action_logout){

            ParseUser.logOut();
            Intent intent = new Intent(MainActivity.this, LoginActivity.class);
            intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK | Intent.FLAG_ACTIVITY_NEW_TASK);
            startActivity(intent);
            Toast.makeText(MainActivity.this, "Logged out successfully", Toast.LENGTH_SHORT).show();
            return true;
        }

        return super.onOptionsItemSelected(item);
    }

    @SuppressWarnings("StatementWithEmptyBody")
    @Override
    public boolean onNavigationItemSelected(MenuItem item) {
        // Handle navigation view item clicks here.
        int id = item.getItemId();

        if (id == R.id.nav_camara) {
            Toast.makeText(MainActivity.this, "Profile page will created soon..", Toast.LENGTH_SHORT).show();
        } else if (id == R.id.nav_gallery) {
            Toast.makeText(MainActivity.this, "Offer Ride page", Toast.LENGTH_SHORT).show();
            Intent intent= new Intent(MainActivity.this,OfferActivity.class);
            startActivity(intent);

        } else if (id == R.id.nav_slideshow) {

            Toast.makeText(MainActivity.this, "Find Ride page", Toast.LENGTH_SHORT).show();
            Intent intent= new Intent(MainActivity.this,FindActivity.class);
            startActivity(intent);

        } else if (id == R.id.nav_manage) {
            Toast.makeText(MainActivity.this, "Tool Page will created Soon", Toast.LENGTH_SHORT).show();
        } else if (id == R.id.nav_share) {

            Toast.makeText(MainActivity.this, "Share page will created Soon..", Toast.LENGTH_SHORT).show();

        } else if (id == R.id.nav_send) {

            Toast.makeText(MainActivity.this, "Send page will created Soon...", Toast.LENGTH_SHORT).show();

        }

        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        drawer.closeDrawer(GravityCompat.START);
        return true;
    }

    @Override
    public void onMapReady(GoogleMap googleMap) {
        mMap = googleMap;
        // Add a marker in Jaipur and move the camera
        LatLng jaipur = new LatLng(26, 75.80);
        LatLng bikaner= new LatLng(28.0167, 73.3119);
        LatLng bangalore=new LatLng(12.9667, 77.5667);
        LatLng delhi=new LatLng(28.6100, 77.2300);
        mMap.setMapType(GoogleMap.MAP_TYPE_TERRAIN);
        mMap.setMyLocationEnabled(true);
        mMap.addMarker(new MarkerOptions().position(jaipur).title("Cars available in Jaipur"))
                .setIcon(BitmapDescriptorFactory.fromResource(R.drawable.caricon));
        mMap.moveCamera(CameraUpdateFactory.newLatLng(jaipur));
        mMap.addMarker(new MarkerOptions().position(bikaner).title("Cars available in Bikaner"))
                .setIcon(BitmapDescriptorFactory.fromResource(R.drawable.caricon));
        mMap.moveCamera(CameraUpdateFactory.newLatLng(bikaner));
        mMap.addMarker(new MarkerOptions().position(bangalore).title("Cars available in Bangalore"))
                .setIcon(BitmapDescriptorFactory.fromResource(R.drawable.caricon));
        mMap.moveCamera(CameraUpdateFactory.newLatLng(bangalore));
        mMap.addMarker(new MarkerOptions().position(delhi).title("Cars available in Delhi"))
                .setIcon(BitmapDescriptorFactory.fromResource(R.drawable.caricon));
        mMap.moveCamera(CameraUpdateFactory.newLatLng(delhi));

    }
}

注册活动

import android.app.ProgressDialog;
import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;

import com.parse.ParseException;
import com.parse.ParseUser;
import com.parse.SignUpCallback;

import butterknife.ButterKnife;
import butterknife.InjectView;

public class SignupActivity extends AppCompatActivity {
    private static final String TAG = "SignupActivity";

    @InjectView(R.id.input_name)
    EditText _nameText;
    @InjectView(R.id.input_email) EditText _emailText;
    @InjectView(R.id.input_password) EditText _passwordText;
    @InjectView(R.id.input_repassword) EditText _passwordAgainText;
    @InjectView(R.id.input_mobile) EditText _mobileText;
    @InjectView(R.id.btn_signup)
    Button _signupButton;
    @InjectView(R.id.link_login)
    TextView _loginLink;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_signup);
        ButterKnife.inject(this);

        _signupButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                signup();
            }
        });

        _loginLink.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                // Finish the registration screen and return to the Login activity
                finish();
            }
        });
    }

    public void signup() {
        Log.d(TAG, "Signup");

        if (!validate()) {
            onSignupFailed();
            return;
        }
        else {
            _signupButton.setEnabled(false);

            final ProgressDialog progressDialog = new ProgressDialog(SignupActivity.this,
                    R.style.AppTheme_Dark_Dialog);
            progressDialog.setIndeterminate(true);
//            progressDialog.setMessage("Creating Account...");
            progressDialog.show();

            new android.os.Handler().postDelayed(
                    new Runnable() {
                        public void run() {
                            onSignupSuccess();
                            progressDialog.dismiss();
                        }
                    }, 3000);
        }
    }


    public void onSignupSuccess() {
        _signupButton.setEnabled(true);
        setResult(RESULT_OK, null);
        //code for succefully signed up
        ParseUser user =new ParseUser();
        user.setUsername(_nameText.getText().toString());
        user.setEmail(_emailText.getText().toString());
        user.setPassword(_passwordText.getText().toString());


        user.signUpInBackground(new SignUpCallback() {
            @Override
            public void done(ParseException e) {
                if (e != null) {
                    // Show the error message
                    Toast.makeText(SignupActivity.this, e.getMessage(),
                            Toast.LENGTH_LONG).show();
                } else {
                    // Start an intent for the dispatch activity
                    Intent intent = new Intent(SignupActivity.this, MainActivity.class);
                    intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK |
                            Intent.FLAG_ACTIVITY_NEW_TASK);
                    startActivity(intent);
                }
            }
        });
    }

    public void onSignupFailed() {
        Toast.makeText(getBaseContext(), "Login failed", Toast.LENGTH_LONG).show();
        _signupButton.setEnabled(true);

    }

    public boolean validate() {
        boolean valid = true;

        String name = _nameText.getText().toString();
        String email = _emailText.getText().toString();
        String password = _passwordText.getText().toString();
        String password_again= _passwordAgainText.getText().toString();
        String mobile=_mobileText.getText().toString();


        if (name.isEmpty() || name.length() < 3) {
            _nameText.setError("at least 3 characters");
            valid = false;
        } else {
            _nameText.setError(null);
        }

        if (email.isEmpty() || !android.util.Patterns.EMAIL_ADDRESS.matcher(email).matches()) {
            _emailText.setError("enter a valid email address");
            valid = false;
        } else {
            _emailText.setError(null);
        }

        if (password.isEmpty() || password.length() < 4 || password.length() > 10) {
            _passwordText.setError("between 4 and 10 alphanumeric characters");
            valid = false;
        } else {
            _passwordText.setError(null);
        }


        if (name.isEmpty() || name.length() < 3) {
            _nameText.setError("at least 3 characters");
            valid = false;
        } else {
            _passwordAgainText.setError(null);
        }

        if (!password.equals(password_again)){
            _passwordAgainText.setError("Password Do not match");
            valid = false;
        }
        else {
            _passwordAgainText.setError(null);
        }

        if (mobile.isEmpty() || mobile.length() < 10 || mobile.length() >10) {
            _mobileText.setError("Enter correct Mobile No.");
            valid = false;
        }
        else {
            _mobileText.setError(null);
        }
        return valid;

    }
}

ParseApplication.java

import android.app.Application;

import com.parse.Parse;
import com.parse.ParseACL;
import com.parse.ParseUser;

public class ParseApplication extends Application {
    @Override
    public void onCreate() {
        super.onCreate();

        // Enable Local Datastore.
        Parse.enableLocalDatastore(this);

        Parse.initialize(this, "key", "key");
        ParseUser.enableRevocableSessionInBackground();

        ParseUser.enableAutomaticUser();
        ParseACL defaultACL = new ParseACL();

        // If you would like all objects to be private by default, remove this
        // line.
        defaultACL.setPublicReadAccess(true);

        ParseACL.setDefaultACL(defaultACL, true);
    }
}

清单文件

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.developer.akshay.youmego" >

    <!-- To auto-complete the email text field in the login form with the user's emails -->
    <uses-permission android:name="android.permission.GET_ACCOUNTS" />
    <uses-permission android:name="android.permission.READ_PROFILE" />
    <uses-permission android:name="android.permission.READ_CONTACTS" />
    <uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />


    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />


    <application
        android:name=".ParseApplication"
        android:allowBackup="true"
        android:icon="@drawable/logo_main"
        android:label="@string/app_name"
        android:supportsRtl="true"
        android:theme="@style/AppTheme.NoActionBar" >
        <meta-data
            android:name="com.google.android.geo.API_KEY"
            android:value="@string/google_maps_key" />
        <activity
            android:name=".Splash"
            android:label="@string/app_name"
            android:theme="@style/AppTheme.NoActionBar" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.VIEW" />
            </intent-filter>
        </activity>
        <activity android:name=".MapsActivity"/>
        <activity android:name=".SignupActivity"
            android:theme="@style/AppTheme"/>
        <activity android:name=".LoginActivity"
            android:theme="@style/AppTheme">
        </activity>
        <activity android:name=".OfferActivity"
            android:theme="@style/AppTheme">
        </activity>
        <activity android:name=".FindActivity"
            android:theme="@style/AppTheme">
        </activity>

    </application>

</manifest>

1. 当我运行应用程序时。即使我从用户注销，MainActivity.java也会打开。
2. 我想让应用程序也使用电子邮件ID登录。
3. 如何检索当前用户详细信息。像用户名和所有。
4. 注册页面：能够使用相同的手机号码创建帐户。如何解决？

Answer 1

我不知道第一个问题的解决方案，因为即使我没有让它工作。其中一种解决方法是在用户登录时临时将用户信息存储在共享首选项中，并在用户退出应用程序时将其清除。

    private void setUserPreferences(String username){
        SharedPreferences sharedPreferences=getSharedPreferences("DEFAULT_SP", Context.MODE_PRIVATE);
        SharedPreferences.Editor editor=sharedPreferences.edit();
        editor.putString("username", username);
        editor.commit();
    }

    private String getUserPreferences(){
        SharedPreferences sharedPreferences=getSharedPreferences("DEFAULT_SP", Context.MODE_PRIVATE);
        return sharedPreferences.getString("username", null);
    }

    private void clearUserPreferences(){
        SharedPreferences sharedPreferences=getSharedPreferences("DEFAULT_SP", Context.MODE_PRIVATE);
        SharedPreferences.Editor editor=sharedPreferences.edit();
        editor.clear();
        editor.commit();
    }

现在，您可以在登录应用程序并注销应用程序时调用这些功能。不是一个可行的解决方案，而是我现在所拥有的一切。

此外，您无法在解析时使用email-id登录，您需要用户名。所以你可以做的是找到与该电子邮件关联的用户名，然后使用该用户名登录解析。

private String mUsername=null;
private void getParseUsername(String email){
    ParseQuery<ParseObject> query = ParseQuery.getQuery("User");
    query.whereEqualTo("email", email);
    query.findInBackground(new FindCallback<ParseObject>() {
        public void done(List<ParseObject> parseList, ParseException e) {
            if (e == null) {
                //assuming you don't have same email id's in the parse database
                //, I don't think that's even allowed.
                mUsername = parseList.get(0).getString("");
            } else {
                Log.d("parseList", "Error: " + e.getMessage());
            }
        }
    });
}

要检索用户信息，只需输入以下代码：

ParseUser.getCurrentUser().getUsername()

对于您的第四个问题，如果我理解正确，您不希望用户注册已注册的手机号码。

private boolean mDuplicatePhoneNo=false;
private void isPhoneNumberDuplicate(String phoneNo)
    ParseQuery<ParseObject> query = ParseQuery.getQuery("User");
    //Here phone_no is the field name in which you have stored your phone numbers
    //Make sure they are in string format.
    query.whereEqualTo("phone_no", phone);
    query.findInBackground(new FindCallback<ParseObject>() {
        public void done(List<ParseObject> parseList, ParseException e) {
            if (e == null) {
                if(phoneNo.equals(parseList.get(0).getString("phone_no"))){
                    mDuplicatePhoneNo=true;
                }
            } else {
                Log.d("parseList", "Error: " + e.getMessage());
            }
        }
});

另请务必访问https://parse.com/docs/android/guide#getting-started 为了更好的指导。

Answer 2

根据您的登录和注册活动，只需使用SharedPrefences，您也​​可以使用解析会话管理..