Question

我正在尝试为我的应用创建一个登录屏幕，该登录屏幕在3次登录尝试失败后禁用登录按钮5分钟。

但是，在我的应用中，可以通过关闭应用并再次启动来轻松再次启用该按钮。

我该如何解决这个问题？

代码：

public class LogIn extends Activity {

    EditText username = null;
    EditText password = null;

    Button loginbutton = null;

    int counter = 2;

    String user = "admin";
    String pw = "password";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_log_in);
        username = (EditText) findViewById(R.id.username);
        password = (EditText) findViewById(R.id.password);

        loginbutton = (Button) findViewById(R.id.loginbutton);
        loginbutton.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v)
            {   String name = username.getText().toString();
                String pass = password.getText().toString();

                if (name.equals(user) && pass.equals(pw))
                // Successful Login
                {   Intent intent = new Intent(LogIn.this, MainApp.class);
                    startActivity(intent);
                }

                else if (name.equals("") || pass.equals(""))
                // Missing username or password
                {   Toast alert = Toast.makeText(LogIn.this, "Please enter a username or password", Toast.LENGTH_SHORT);
                    alert.show();
                }

                else if (counter == 0)
                // Disable button after 3 failed attempts
                {   loginbutton.setEnabled(false);

                    Toast alert = Toast.makeText(LogIn.this, "Login Disabled for 5 mins", Toast.LENGTH_SHORT);
                    alert.show();

                    final Handler handler = new Handler();
                    handler.postDelayed(new Runnable()
                    {   @Override
                        public void run()
                        {   loginbutton.setEnabled(true);
                            counter = 2;
                        }
                    }, 300000);
                }

                else
                // Wrong password
                {   Toast alert = Toast.makeText(LogIn.this, "Wrong Credentials", Toast.LENGTH_SHORT);
                    alert.show();
                    counter--;  
                };
            }
        });
    };
}

Answer 1

您可以使用共享首选项来存储任何失败尝试。如果用户无法登录该应用程序，您可以在共享的首选项中存储该尝试的尝试次数和时间。

SharedPreferences pref = this.getSharedPreferences("Sample", Context.MODE_PRIVATE);
SharedPreferences.Editor editor = pref.edit();
editor.putString("ATTEMPTs", "5");
editor.putString("ATTEMPT_Time", System.currentTimeMillis());
editor.commit();

启动登录活动时，请检查共享首选项中的尝试次数，并相应地启用或禁用登录按钮。

SharedPreferences  pref = this.getSharedPreferences("Sample", Context.MODE_PRIVATE);
String no_attempt = pref.getString("ATTEMPTs", "");
String time= pref.getString("ATTEMPT_Time"," ");

if(no_attempt>5 && Long.parseLong(time)>(System.currentTimeMillis()-300000))
{
  btn_login.setVisibilty(View.INVISIBLE);
}
else
{
   //login
}

Answer 2

在这种情况下，您可以将CurrentTime保存在首选项中，并在尝试重新登录之前进行检查

这是偏好的工作方式

// Initiate the preference with Preference Filename and Access Mode for other Apps

SharedPreferences pref = getSharedPreferences("LoginTrack", Context.MODE_PRIVATE); // "LoginTrack" is the preference Name

// read the preference

long l = prefs.getLong("LastLoginDateTime", new Date().getTime()); 
String Attempts= pref.getString("MaxAttempts", "");


//To edit and save preferences again when you try login

Date dt = new Date(); // Current Time to Track loginTime
prefs.edit().putLong("LastLoginDateTime", dt.getTime()).commit();
prefs.edit().putString("MaxAttempts", "5").commit();

检索数据后，根据需要进行验证

尝试失败后暂时禁用登录

2 个答案: