android mvc 实现一个登录功能

这里给出一个简单的Android MVC实现登录功能的例子：

Model类：User.java

public class User {
    private String username;
    private String password;

    public User(String username, String password) {
        this.username = username;
        this.password = password;
    }

    public String getUsername() {
        return username;
    }

    public String getPassword() {
        return password;
    }
}

View类：LoginActivity.java

public class LoginActivity extends AppCompatActivity {
    private EditText etUsername;
    private EditText etPassword;
    private Button btnLogin;

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

        etUsername = findViewById(R.id.et_username);
        etPassword = findViewById(R.id.et_password);
        btnLogin = findViewById(R.id.btn_login);

        btnLogin.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                String username = etUsername.getText().toString();
                String password = etPassword.getText().toString();

                UserController userController = new UserController();
                User user = userController.login(username, password);

                if (user != null) {
                    Toast.makeText(LoginActivity.this, "登录成功", Toast.LENGTH_SHORT).show();
                } else {
                    Toast.makeText(LoginActivity.this, "用户名或密码错误", Toast.LENGTH_SHORT).show();
                }
            }
        });
    }
}

Controller类：UserController.java

public class UserController {
    private List<User> userList;

    public UserController() {
        userList = new ArrayList<>();
        userList.add(new User("admin", "admin123"));
        userList.add(new User("user1", "user123"));
        userList.add(new User("user2", "user123"));
    }

    public User login(String username, String password) {
        for (User user : userList) {
            if (user.getUsername().equals(username) && user.getPassword().equals(password)) {
                return user;
            }
        }
        return null;
    }
}

在这个例子中，View层负责用户界面的展示和交互；Model层负责数据的处理和存储；Controller层负责业务逻辑的处理。用户在View层输入用户名和密码后，点击登录按钮触发登录事件，View层将用户名和密码传递给Controller层进行业务处理，Controller层调用Model层的接口进行数据查询，查询结果返回给Controller层，Controller层再将结果返回给View层进行展示。