将 facebook id 和电子邮件保存到本地数据库

Question

我开始学习如何通过 facebook 登录用户。在我的代码中，有一个带有 FB 登录按钮的布局。当用户单击它时，它会打开 facebook 访问页面，并在成功登录后显示相同的布局，其中包含个人资料图片和名称。我想获取电子邮件 ID 和 Facebook 用户 ID 并将其保存到本地数据库，并在下次登录时检查数据库中的电子邮件 ID 以登录。这是因为，即使用户从设置中清除数据，用户也不必再次访问 Facebook 访问页面。它将搜索本地数据库并登录。

SQLite 数据库

public class SQLiteHandler extends SQLiteOpenHelper {

    private static final String TAG = SQLiteHandler.class.getSimpleName();

    // All Static variables
    // Database Version
    private static final int DATABASE_VERSION = 1;

    // Database Name
    private static final String DATABASE_NAME = "android_api";

    // Login table name
    private static final String TABLE_USER = "user";

    // Login Table Columns names
    private static final String KEY_ID = "id";
    private static final String KEY_EMAIL = "email";
    private static final String KEY_UID = "uid";

    public SQLiteHandler(Context context) {
        super(context, DATABASE_NAME, null, DATABASE_VERSION);
    }

    // Creating Tables
    @Override
    public void onCreate(SQLiteDatabase db) {
        String CREATE_LOGIN_TABLE = "CREATE TABLE " + TABLE_USER + "("
                + KEY_ID + " INTEGER PRIMARY KEY,"
                + KEY_EMAIL + " TEXT UNIQUE," + KEY_UID + " TEXT"+")";
        db.execSQL(CREATE_LOGIN_TABLE);

        Log.d(TAG, "Database tables created");
    }

    // Upgrading database
    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        // Drop older table if existed
        db.execSQL("DROP TABLE IF EXISTS " + TABLE_USER);

        // Create tables again
        onCreate(db);
    }

    /**
     * Storing user details in database
     * */
    public void addUser(String name, String email, String uid, String created_at) {
        SQLiteDatabase db = this.getWritableDatabase();

        ContentValues values = new ContentValues();
        values.put(KEY_EMAIL, email); // Email
        values.put(KEY_UID, uid); // Email

        // Inserting Row
        long id = db.insert(TABLE_USER, null, values);
        db.close(); // Closing database connection

        Log.d(TAG, "New user inserted into sqlite: " + id);
    }

    /**
     * Getting user data from database
     * */
    public HashMap<String, String> getUserDetails() {
        HashMap<String, String> user = new HashMap<String, String>();
        String selectQuery = "SELECT  * FROM " + TABLE_USER;

        SQLiteDatabase db = this.getReadableDatabase();
        Cursor cursor = db.rawQuery(selectQuery, null);
        // Move to first row
        cursor.moveToFirst();
        if (cursor.getCount() > 0) {
            user.put("email", cursor.getString(1));
            user.put("uid", cursor.getString(2));
        }
        cursor.close();
        db.close();
        // return user
        Log.d(TAG, "Fetching user from Sqlite: " + user.toString());

        return user;
    }

    /**
     * Re crate database Delete all tables and create them again
     * */
    public void deleteUsers() {
        SQLiteDatabase db = this.getWritableDatabase();
        // Delete All Rows
        db.delete(TABLE_USER, null, null);
        db.close();

        Log.d(TAG, "Deleted all user info from sqlite");
    }

}

主要活动

public class MainActivity extends Activity {
    CallbackManager callbackManager;
    Button share,details;
    ShareDialog shareDialog;
    LoginButton login;
    ProfilePictureView profile;
    Dialog details_dialog;
    TextView details_txt;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        FacebookSdk.sdkInitialize(getApplicationContext());
        setContentView(R.layout.activity_main);

        callbackManager = CallbackManager.Factory.create();
        login = (LoginButton)findViewById(R.id.login_button);
        profile = (ProfilePictureView)findViewById(R.id.picture);
        shareDialog = new ShareDialog(this);
        share = (Button)findViewById(R.id.share);
        details = (Button)findViewById(R.id.details);
        login.setReadPermissions("public_profile email");
        share.setVisibility(View.INVISIBLE);
        details.setVisibility(View.INVISIBLE);
        details_dialog = new Dialog(this);
        details_dialog.setContentView(R.layout.dialog_details);
        details_dialog.setTitle("Details");
        details_txt = (TextView)details_dialog.findViewById(R.id.details);
        details.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                details_dialog.show();
            }
        });


        if(AccessToken.getCurrentAccessToken() != null){
            RequestData();
            share.setVisibility(View.VISIBLE);
            details.setVisibility(View.VISIBLE);
        }
        login.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                if(AccessToken.getCurrentAccessToken() != null) {
                    share.setVisibility(View.INVISIBLE);
                    details.setVisibility(View.INVISIBLE);
                    profile.setProfileId(null);
                }
            }
        });
        share.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                ShareLinkContent content = new ShareLinkContent.Builder().build();
                shareDialog.show(content);

            }
        });
        login.registerCallback(callbackManager, new FacebookCallback<LoginResult>() {
            @Override
            public void onSuccess(LoginResult loginResult) {

                if(AccessToken.getCurrentAccessToken() != null){
                    RequestData();
                    share.setVisibility(View.VISIBLE);
                    details.setVisibility(View.VISIBLE);
                }
            }

            @Override
            public void onCancel() {

            }

            @Override
            public void onError(FacebookException exception) {
            }
        });

    }
    public void RequestData(){
        GraphRequest request = GraphRequest.newMeRequest(AccessToken.getCurrentAccessToken(), new GraphRequest.GraphJSONObjectCallback() {
            @Override
            public void onCompleted(JSONObject object,GraphResponse response) {

                JSONObject json = response.getJSONObject();
                try {
                    if(json != null){
                        String text = "<b>Name :</b> "+json.getString("name")+"<br><br><b>Email :</b> "+json.getString("email")+"<br><br><b>Profile link :</b> "+json.getString("link");
                        details_txt.setText(Html.fromHtml(text));
                        profile.setProfileId(json.getString("id"));
                    }

                } catch (JSONException e) {
                    e.printStackTrace();
                }
            }
        });
        Bundle parameters = new Bundle();
        parameters.putString("fields", "id,name,link,email,picture");
        request.setParameters(parameters);
        request.executeAsync();
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        callbackManager.onActivityResult(requestCode, resultCode, data);
    }



}

Answer 1

解决方法如下：

无论如何，如果用户从设置中清除数据，您的数据库将被清空。

Answer 2

关于如何完成有两种情况

首先： 您让用户通过 facebook 登录并将其访问令牌（由 facebook 提供）存储在 sharedpreferences 中，并在每次用户时检查 sharedpreferences卷土重来你的应用程序。这里访问令牌的过期由 facebook 处理，所以你不那么头疼了。

其次： 在你的后端获取 facebook 的访问令牌并将其替换为你生成的访问令牌，在这里你要处理你的令牌过期远程服务器。

然而，在这两种情况下，访问令牌都存储在您的 sharedpreferences 中，或者即使您将其存储在您的 sqlite 本地数据库中（您不应该这样做），在清除时app 来自 sharedpreferences 和 sqlite db 的设置数据被清除，因此无法确认用户身份。因此，用户必须重新登录，这根本不是一件坏事，应该允许这样做。

将 facebook id 和电子邮件保存到本地数据库

save facebook id and email to local database

android

facebook

android-sqlite