3.27

简单的登录

public class MainActivity extends AppCompatActivity {

    private Button signUpButton;

    @Override
    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        signUpButton = findViewById(R.id.SignUpButton);

        signUpButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                // 创建一个意图对象，用于启动注册页面的活动
                Intent intent = new Intent(MainActivity.this, SignUpActivity.class);
                // 启动注册页面的活动
                startActivity(intent);
            }
        });
    }


    /**
     * function: 登录
     * */
    public void login(View view){

        EditText EditTextAccount = findViewById(R.id.UserNameEdit);
        EditText EditTextPassword = findViewById(R.id.PassWordEdit);
        String account = EditTextAccount.getText().toString();
        String password = EditTextPassword.getText().toString();


        // 检查是否为教师账号，如果是则直接跳转到教师界面
        if (account.equals("teacher") && password.equals("teacher")) {
            Intent intent = new Intent(MainActivity.this, teacher.class);
            startActivity(intent);
        } else {
            new Thread() {
                @Override
                public void run() {
                    StudentDao studentDao = new StudentDao();
                    int msg = studentDao.login(EditTextAccount.getText().toString(), EditTextPassword.getText().toString());
                    hand1.sendEmptyMessage(msg);
                }
            }.start();
        }

    }

    @SuppressLint("HandlerLeak")
    final Handler hand1 = new Handler() {
        @Override
        public void handleMessage(Message msg) {
            if (msg.what == 1) {
                Toast.makeText(getApplicationContext(), "登录成功", Toast.LENGTH_LONG).show();
                // 登录成功后启动新的活动
                startActivity(new Intent(MainActivity.this, MainActivity2.class));
            } else if (msg.what == 0) {
                Toast.makeText(getApplicationContext(), "登录失败", Toast.LENGTH_LONG).show();
            } else if (msg.what == 2) {
                Toast.makeText(getApplicationContext(), "密码错误", Toast.LENGTH_LONG).show();
            } else if (msg.what == 3) {
                Toast.makeText(getApplicationContext(), "账号不存在", Toast.LENGTH_LONG).show();
            }
        }
    };

}