android - 应用程序关闭时保持用户登录 - Android Studio - MySQL

Question

我创建了一个应用程序，其中组的用户列表已放置在 MySQL 上的数据库中，分配给他们的用户名、密码和变量已上传。

下面是登录 Activity ，允许用户登录并转到自己的用户区域(还有一个 loginrequest 类可以传递参数)。

我需要帮助的是让应用程序保持登录状态，直到该用户注销，即使他们已经关闭了应用程序。

如果可能的话，这是否还允许我在应用程序对个人用户关闭时发送用户通知？

谢谢。

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_login);


    final EditText etUsername = (EditText) findViewById(R.id.etUsername);
    final EditText etPassword = (EditText) findViewById(R.id.etPassword);
    final Button bLogin = (Button) findViewById(R.id.bLogin);
    final TextView registerLink = (TextView) findViewById(R.id.tvRegisterHere);

    //Register Here button
    registerLink.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Intent registerIntent = new Intent(LoginActivity.this, RegisterActivity.class);
            LoginActivity.this.startActivity(registerIntent);
        }
    });

    //Login Button
    bLogin.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            //Taking the username and password and converting it to a string
            final String username = etUsername.getText().toString();
            final String password = etPassword.getText().toString();
            Response.Listener<String> responseListener = new Response.Listener<String>() {
                @Override
                public void onResponse(String response) {
                    try {
                        //Taking the JSONObject from the 000webhost database

                        JSONObject jsonResponse = new JSONObject(response);
                        //If the response is successful ie is there a username and password that match
                        boolean success = jsonResponse.getBoolean("success");
                        if (success){
                            //Gather the information below
                            String name = jsonResponse.getString("name");
                            int var1 = jsonResponse.getInt("var1");
                            int var2 = jsonResponse.getInt("var2");
                            int var3 = jsonResponse.getInt("var3");
                            int var4 = jsonResponse.getInt("var4");



                            Intent intent = new Intent(LoginActivity.this, UserAreaActivity.class);
                            intent.putExtra("name", name);
                            intent.putExtra("username", username);
                            intent.putExtra("var1", var1);
                            intent.putExtra("var2", var2);
                            intent.putExtra("var3", var3);
                            intent.putExtra("var4", var4);
                            intent.putExtra("password", password);

                            //Start the User Area Activity

                            LoginActivity.this.startActivity(intent);




                        }else{

                            AlertDialog.Builder builder = new AlertDialog.Builder(LoginActivity.this);
                            builder.setMessage("Login Failed")
                                    .setNegativeButton("Retry", null)
                                    .create()
                                    .show();
                        }


                    } catch (JSONException e) {
                        e.printStackTrace();
                    }
                }
            };



            LoginRequest loginRequest = new LoginRequest(username, password, responseListener);
            RequestQueue queue = Volley.newRequestQueue(LoginActivity.this);
            queue.add(loginRequest);

        }
    });

}

Answer 1

您可以使用 SharedPreferences 来解决您的问题。

用它来验证用户是否已启动“ session ”

      private SharedPreferences sharedpreferences;    

    sharedpreferences=getApplicationContext().getSharedPreferences("Preferences", 0);
                    String login = sharedpreferences.getString("LOGIN", null);


                    if (login != null) {
         //put your code if user is logged. For example, go to another activity
        }else {

// to go login activity
}

用它来设置点击登录按钮时的“ session ”

   SharedPreferences.Editor editor = sharedpreferences.edit();
                        editor.putString("LOGIN", newUser.getEmail_user());
                        editor.commit

在注销按钮上使用此功能

 Editor editor = sharedpreferences.edit();
                    editor.remove("LOGIN"); 
                    editor.commit();